A flow instrument reads and displays the value of a particular property of a system at a point, or displays the difference in the value of a property between two points.
Instrumentation is typically for the purpose of determining the value of the property at a point in time. It is not the purpose of an instrument to record or integrate the values over time (although they may be connected to recording devices that do perform such a function). This entity provides for all forms of mechanical flow instrument (thermometers, pressure gauges etc.) and electrical flow instruments (ammeters, voltmeters etc.)
An actuator is a mechanical device for moving or controlling a mechanism or system. An actuator takes energy, usually created by air, electricity, or liquid, and converts that into some kind of motion.
A controller is a device that monitors inputs and controls outputs within a building automation system.
A controller may be physical (having placement within a spatial structure) or logical (a software interface or aggregated within a programmable physical controller).
Figure 177 illustrates controller type use.
Figure 178 illustrates controller port use.
A sensor is a device that measures a physical quantity and converts it into a signal which can be read by an observer or by an instrument.
Figure 179 illustrates sensor type use.
Figure 180 illustrates sensor port use.
An alarm is a device that signals the existence of a condition or situation that is outside the boundaries of normal expectation or that activates such a device.
Alarms include the provision of break glass buttons and manual pull boxes that are used to activate alarms.
A unitary control element combines a number of control components into a single product, such as a thermostat or humidistat.
A unitary control element provides a housing for an aggregation of control or electrical distribution elements that, in combination, perform a singular (unitary) purpose. Each item in the aggregation may have its own geometric representation and location.
Figure 181 illustrates unitary control element type use.
Figure 182 illustrates unitary control element port use.
Definition from ISO/CD 10303-42:1992: A vertex point is a vertex which has its geometry defined as a point.
NOTE Corresponding ISO 10303 entity: vertex_point. Please refer to ISO/IS 10303-42:1994, p. 130 for the final definition of the formal standard. Due to the general IFC model specification rule not to use multiple inheritance, the subtype relationship to geometric_representation_item is not included.
HISTORY New Entity in IFC2x.
Informal proposition:
- The domain of the vertex is formally defined to be the domain of its vertex point.
"
2431;IfcEdgeCurve;"
Definition from ISO/CD 10303-42:1992: An edge curve is
a special subtype of edge which has its geometry fully defined.
The geometry is defined by associating the edge with a curve
which may be unbounded. As the topological and geometric
directions may be opposed, an indicator (same sense) is used to
identify whether the edge and curve directions agree or are
opposed. The Boolean value indicates whether the curve direction
agrees with (TRUE) or is in the opposite direction (FALSE) to the
edge direction. Any geometry associated with the vertices of the
edge shall be consistent with the edge geometry. Multiple edges
can reference the same curve.
Figure 334 illustrates an example where the edge geometry is given by an unbounded curve, here IfcCircle. The bounds are provided by the EdgeStart and EdgeEnd, the topological direction of the IfcEdgeCurve opposes the direction of the IfcCircle by SameSense = FALSE.
![]() |
Figure 334 — Edge curve |
NOTE Corresponding ISO 10303 entity: edge_curve. Please refer to ISO/IS 10303-42:1994, p. 132
for the final definition of the formal standard. Due to the general IFC model specification rule not to use multiple inheritance, the subtype relationship to geometric_representation_item is not included.
Informal propositions:
- The domain of the edge curve is formally defined to be the
domain of its edge geometry as trimmed by the vertices. This
domain does not include the vertices.
- An edge curve has non-zero finite extent.
- An edge curve is a manifold.
- An edge curve is arcwise connected.
- The edge start is not a part of the edge domain.
- The edge end is not a part of the edge domain.
- Vertex geometry shall be consistent with edge geometry.
"
2434;IfcSubedge;"
Definition from ISO/DIS 10303-42:1999(E): A subedge is an edge whose domain is a connected portion of the domain of an existing edge. The topological constraints on a subedge are the same as those on an edge.
Informal propositions:
- The domain of the subedge is formally defined to be the domain of the parent edge, as trimmed by the subedge start vertex and subedge end vertex.
- The start vertex and end vertex shall be within the union of the domains of the vertices of the parent edge and the domain of the parent edge.
NOTE Corresponding ISO 10303 entity: subedge. Please refer to ISO/DIS 10303-42:1999(E), p. 194 for the final definition of the formal standard.
HISTORY New entity in IFC2x2.
"
2436;IfcFace;"
Definition from ISO/CD 10303-42:1992: A face is a topological
entity of dimensionality 2 corresponding to the intuitive notion of a piece of
surface bounded by loops. Its domain, if present, is an oriented, connected,
finite 2-manifold in Rm. A face domain shall not have handles
but it may have holes, each hole bounded by a loop. The domain of the
underlying geometry of the face, if present, does not contain its bounds, and 0
< Ξ < ∞.
A face is represented by its bounding loops, which are defined as face
bounds. A face has a topological normal n and the tangent to a loop is t. For a
loop bounding a face with defined geometry, the cross product n x t points
toward the interior of the face. That is, each loop runs counter-clockwise
around the face when viewed from above, if we consider the normal n to point
up. With each loop is associated a BOOLEAN flag to signify whether the loop
direction is oriented with respect to the face normal (TRUE) or should be
reversed (FALSE).
A face shall have at least one bound, and the loops shall not intersect.
One loop is optionally distinguished as the outer loop of the face. If so, it
establishes a preferred way of embedding the face domain in the plane, in which
the other bounding loops of the face are inside the outer bound. Because the
face domain is arcwise connected, no inner loop will contain any other loop.
This is true regardless of which embedding in the plane is chosen.
The edges and vertices referenced by the loops of a face form a graph,
of which the individual loops are the connected components. The Euler equation
(1) for this graph becomes:
![]()
where Gli is the graph genus of the
i th loop.
NOTE Corresponding ISO 10303 entity: face. No subtypes of face have been incorporated
into this IFC Release. Please refer to ISO/IS 10303-42:1994, p. 140 for the
final definition of the formal standard. The WR1 has not been incorporated,
since it is always satisfied, due to the fact that only poly loops exist for
face bounds.
HISTORY New class in IFC Release 1.0
Informal propositions:
- No edge shall be referenced by the face more than twice.
- Distinct face bounds of the face shall have no common vertices.
- If geometry is present, distinct loops of the same face shall not
intersect.
- The face shall satisfy the Euler Equation: (number of vertices) -
(number of edges) - (number of loops) + (sum of genus for loops) = 0.
"
2440;IfcFaceSurface;"
Definition from ISO/CD 10303-42:1992: A face surface
(IfcFaceSurface) is a subtype of face in which the geometry is defined by an
associated surface. The portion of the surface used by the face shall be
embeddable in the plane as an open disk, possibly with holes. However, the
union of the face with the edges and vertices of its bounding loops need not be
embeddable in the plane. It may, for example, cover an entire sphere or torus.
As both a face and a geometric surface have defined normal directions, a
BOOLEAN flag (the orientation attribute) is used to indicate whether the
surface normal agrees with (TRUE) or is opposed to (FALSE) the face normal
direction. The geometry associated with any component of the loops of the face
shall be consistent with the surface geometry, in the sense that the domains of
all the vertex points and edge curves are contained in the face geometry
surface. A surface may be referenced by more than one face surface.
NOTE Corresponding ISO 10303 entity:
face_surface. Please refer to ISO/IS 10303-42:1994, p. 204 for the final
definition of the formal standard. Due to the general IFC model specification
rule not to use multiple inheritance, the subtype relationship to
geometric_representation_item is not included.
HISTORY New class in IFC2x
Informal propositions:
- The domain of the face surface is formally defined to be the domain
of its face geometry as trimmed by the loops, this domain does not include the
bounding loops.
- A face surface has non zero finite extent.
- A face surface is a manifold.
- A face surface is arcwise connected.
- A face surface has surface genus 0.
- The loops are not part of the face domain.
- Loop geometry shall be consistent with face geometry. This implies
that any edge - curves or vertex points used in defining the loops bounding the
face surface shall lie on the face geometry.
- The loops of the face shall not intersect.
"
2444;IfcAdvancedFace;"
An advanced face is a specialization of a face surface that has to meet requirements on using particular topological and geometric representation items for the definition of the faces, edges and vertices.
An IfcAdvancedFace is restricted to:
- have a face surface geometry of type IfcElementarySurface, IfcSweptSurface or IfcBSplineSurface
- have at least on IfcFaceOuterBound as the bound of the face
- have all faces to be bound by IfcEdgeLoop or IfcVertexLoop
- have all edges to have an edge curve geometry
- have the edge curve geometry restricted to IfcLine, IfcConic, IfcPolyline, or IfcBSplineCurve
NOTE Corresponding ISO 10303 entity: advanced_face. Please refer to ISO/IS 10303-511:1999 for
the final definition of the formal standard.
HISTORY New entity in IFC2x4
"
2448;IfcFaceBound;"
Definition from ISO/CD 10303-42:1992: A face bound is a loop which is intended to be used for bounding a face.
NOTE Corresponding ISO 10303 entity: face_bound. Please refer to ISO/IS 10303-42:1994, p. 139 for the final definition of the formal standard.
HISTORY New class in IFC Release 1.0
"
2452;IfcFaceOuterBound;"
Definition from ISO/CD 10303-42:1992: A face outer bound is a special subtype of face bound which carries the additional semantics of defining an outer boundary on the face. No more than one boundary of a face shall be of this type.
NOTE Corresponding ISO 10303 entity: face_outer_bound. Please refer to ISO/IS 10303-42:1994, p. 139 for the final definition of the formal standard.
HISTORY New class in IFC Release 1.0
"
2453;IfcLoop;"
Definition from ISO/CD 10303-42:1992: A loop is a topological
entity constructed from a single vertex, or by stringing together connected
(oriented) edges, or linear segments beginning and ending at the same vertex.
It is typically used to bound a face lying on a surface. A loop has
dimensionality of 0 or 1. The domain of a 0-dimensional loop is a single point.
The domain of a 1-dimensional loop is a connected, oriented curve, but need not
to be manifold. As the loop is a circle, the location of its beginning/ending
point is arbitrary. The domain of the loop includes its bounds, an 0 ≤ Ξ
< ∞.
A loop is represented by a single vertex, or by an ordered collection of
oriented edges, or by an ordered collection of points. A loop is a graph, so
M and the graph genus Gl may be determined by the
graph traversal algorithm. Since M = 1, the Euler equation (1) reduces
in this case to
![]()
where V and El are the number of unique
vertices and oriented edges in the loop and Gl is the genus
of the loop.
NOTE Corresponding ISO 10303 entity: loop, the following subtypes have been incorporated into IFC: poly_loop as IfcPolyLoop, vertex_loop as IfcVertexLoop, edge_loop as IfcEdgeLoop. Please refer to ISO/IS 10303-42:1994, p. 136 for the final definition of the formal standard.
HISTORY New Entity in IFC2x.
Informal propositions:
- A loop has a finite extent.
- A loop describes a closed (topological) curve with coincident start
and end vertices.
"
2457;IfcPolyLoop;"
Definition from ISO/CD 10303-42:1992: A
poly loop is a loop with straight edges bounding a planar region in
space. A poly loop is a loop of genus 1 where the loop is represented
by an ordered coplanar collection of points forming the vertices of the
loop. The loop is composed of straight line segments joining a point in
the collection to the succeeding point in the collection. The closing
segment is from the last to the first point in the collection.
The direction of the loop is in the direction of the line
segments.
NOTE This entity exists primarily to facilitate the efficient communication of faceted B-rep models.
A poly loop shall conform to the following topological
constraints:
- - the loop has the genus of one.
- - the following equation shall be satisfied
-
![]()
The IfcPolyLoop
is always closed and the last segment is from the last IfcCartesianPoint
in the list of Polygon's to the first IfcCartesianPoint.
Therefore the first point shall not be repeated at the end of the list,
neither by referencing the same instance, nor by using an additional
instance of IfcCartesianPoint having the
coordinates as the first point.
NOTE Corresponding ISO 10303 entity: poly_loop. Please refer to ISO/IS
10303-42:1994, p. 138 for the final definition of the formal standard.
Due to the general IFC model specification rule not to use multiple
inheritance, the subtype relationship to geometric_representation_item
is not included. The derived attribute Dim has been
added at this level.
HISTORY New class in IFC Release 1.0
Informal propositions:
- All the points in the polygon defining the poly loop shall be coplanar.
- The first and the last Polygon shall be different by value.
"
2460;IfcVertexLoop;"
Definition from ISO/CD 10303-42:1992: A vertex_loop is a loop of
zero genus consisting of a single vertex. A vertex can exist independently of a
vertex loop. The topological data shall satisfy the following constraint:
![]()
Informal propositions:
- A vertex loop has zero extent and dimensionality.
- The vertex loop has genus 0.
NOTE Corresponding ISO 10303 entity: vertex_loop. Please refer to ISO/IS 10303-42:1994, p. 121 for the final definition of the formal standard.
HISTORY New Entity in IFC2x2.
"
2462;IfcEdgeLoop;"
Definition from ISO/CD 10303-42:1992: An edge_loop is a loop with nonzero extent. It is a path in which the start and end vertices are the same. Its domain, if present, is a closed curve. An edge_loop may overlap itself.
Informal propositions:
- The genus of the IfcEdgeLoop shall be 1 or greater.
- The Euler formula shall be satisfied:
(number of vertices) + genus - (number of edges) = 1;
- No edge may be referenced more than once by the same IfcEdgeLoop with the same sense. For this purpose, an edge which is not an oriented edge is considered to be referenced with the sense TRUE.
NOTE Corresponding ISO 10303 entity: edge_loop. Please refer to ISO/IS 10303-42:1994, p. 122 for the final definition of the formal standard.
HISTORY New Entity in IFC2x2.
"
2467;IfcPath;"
Definition from ISO/CD 10303-42:1992: A path is a topological entity consisting of an ordered collection of oriented edges, such that the edge start vertex of each edge coincides with the edge end of its predecessor. The path is ordered from the edge start of the first oriented edge to the edge end of the last edge. The BOOLEAN value sense in the oriented edge indicates whether the edge direction agrees with the direction of the path (TRUE) or is the opposite direction (FALSE).
An individual edge can only be referenced once by an individual path. An edge can be referenced by multiple paths. An edge can exist independently of a path.
NOTE Corresponding ISO 10303 entity: path. Please refer to ISO/IS 10303-42:1994, p. 133 for the final definition of the formal standard.
HISTORY New Entity in IFC Release 2.0
Informal proposition:
- A path has dimensionality 1.
- A path is arcwise connected.
- The edges of the path do not intersect except at common vertices.
- A path has a finite, non-zero extent.
"
2470;IfcOpenShell;"
Definition from ISO/CD 10303-42:1992: An open shell is a shell of
the dimensionality 2. Its domain, if present, is a finite, connected, oriented,
2-manifold with boundary, but is not a closed surface. It can be thought of as
a closed shell with one or more holes punched in it. The domain of an open
shell satisfies 0
< Ξ < 1. An open shell is
functionally more general than a face because its domain can have handles.
The shell is defined by a collection of faces, which may be oriented
faces. The sense of each face, after taking account of the orientation, shall
agree with the shell normal as defined below. The orientation can be supplied
directly as a BOOLEAN attribute of an oriented face, or be defaulted to TRUE if
the shell member is a face without the orientation attribute.
The following combinatorial restrictions on open shells and geometrical
restrictions on their domains are designed, together with the informal
propositions, to ensure that any domain associated with an open shell is an
orientable manifold.
- Each face reference shall be unique.
- An open shell shall have at least one face.
- A given face may exist in more than one open shell.
The boundary of an open shell consists of the edges that are referenced
only once by the face - bounds (loops) of its faces, together with all of their
vertices. The domain of an open shell, if present, contains all edges and
vertices of its faces.
NOTE Note that this is slightly different from the
definition of a face domain, which includes none of its bounds. For example, a
face domain may exclude an isolated point or line segment. An open shell domain
may not. (See the algorithm for computing below.)
In the current IFC Release only poly loops
(IfcPolyLoop) are defined for bounds of face bound
(IfcFaceBound.Bound). This will allow for faceted B-rep only. For
further specification, including the Euler formulas to be satisfied, please
refer to ISO 10303-42:1994.
NOTE Corresponding ISO 10303 entity:
open_shell, please refer to ISO/IS 10303-42:1994, p.148 for the final
definition of the formal standard.
HISTORY New class in IFC2x.
Informal propositions:
- Every edge shall be referenced exactly twice by the face bounds of
the face.
- Each oriented edge shall be unique.
- No edge shall be referenced by more than two faces.
- Distinct faces of the shell do not intersect, but may share edges or
vertices.
- Distinct edges do not intersect but may share vertices.
- Each face reference shall be unique.
- The loops of the shell shall not be a mixture of poly loop and other
loop types. Note: this is given, since only poly loop is defined as face bound
definition.
- The closed shell shall be an oriented arcwise connected 2-manifold.
- The Euler equation shall be satisfied. Note: Please refer to ISO/IS
10303-42:1994, p.148 for the equation.
"
2478;IfcTask;"
An IfcTask is an identifiable unit of work to be
carried out in a construction project.
A task is typically used to describe an activity for the
construction or installation of products, but is not
limited to these types. For example it might be used to
describe design processes, move operations and other
design, construction and operation related activities as
well.
HISTORY New entity in IFC 1.0. Renamed from IfcWorkTask in IFC 2x.
IFC2x4 CHANGE Attributes TaskTime and PredefinedType added. IfcMove and IfcOrderRequest has been removed in IFC2x4 and are now represented by IfcTask. Further information can be found in the description below.
Type use definition
IfcTask defines the anticipated or actual occurrence
of any task; common information about task types is handled
by IfcTaskType. The IfcTaskType (if present)
may establish the common type name, usage (or predefined)
type, common set of properties, and common product
assignment using IfcRelAssignsToProduct. The
IfcTaskType is attached using the
IfcRelDefinesByType.RelatingType objectified
relationship and is accessible by the inverse
IsTypedBy attribute. Special type information
relating to a task occurrence is asserted using
IfcTask.ObjectType (inherited from
IfcObject). Examples that may be used include fixed
duration, fixed unit or fixed work. IfcTask can be
aggregated to a task type in order to specify a task
sequence or any time related information, e.g. the duration
of a task. Please see the documentation of
IfcTaskType for further information.
Attribute use definition
Each occurrence of IfcTask is given a name that is
indicative of its content (IfcRoot.Name). A textual
description of the task may be provided and this may be
further elaborated by a narrative long description
(IfcProcess.LongDescription). A work method may be
declared for the method of work used in carrying out a
task. A task is identified as being either a milestone task
or not. A milestone task is defined by the marker
IsMilestone. and has no duration. A status and
priority for each task may also be set.
Property set use definition
The property sets relating to IfcTask are defined by
IfcPropertySet and attached by the
IfcRelDefinesByProperties relationship. They are
accessible by the inverse IsDefinedBy relationship.
Such property sets may define task parameters. No property
sets for IfcTask are currently defined by IFC.
Connectivity Use Definition
The relationship IfcRelSequence is used to indicate
control flow. An IfcTask as a successor to an
IfcTask indicates logical sequence how these tasks
should be performed. IfcTask's can be triggered or
can trigger IfcEvent's, which is also defined
through the relationship IfcRelSequence.
Composition use definition
IfcTask may be contained within an IfcTask
using the IfcRelNests relationship. An
IfcTask may in turn nest other IfcTask,
IfcProcedure or IfcEvent entities. Such
nesting indicates decomposed level of detail. From IFC2x4
onwards it is required to have a summary task (root of all
tasks), which is used to define a link to the work plan or
work schedule. All subtasks of the summary tasks are then
implicitly linked to this work plan or work schedule.
Please note that the summary task is used for data
organization and not meant to store typical task
information as defined by the user. It is therefore
recommended that the summary task is hidden from the user
to avoid confusion. Please also note that
IfcRelNests is used to show the dependency between
regular tasks and recurring task definitions (please see
the section about time and duration use definitions).
As shown in Figure 13, the installation of a number of items of equipment within a
particular space may be the subject of a single task which
is identified as 'fix equipment in space 123'.
IfcTask represents the occurrence of a work
performance of a type of process in a construction plan.
![]()
|
Figure 13 — Task visualization |
A task may nest other tasks as sub-items; the nesting
relationship is modeled by IfcRelNests as shown in Figure 14. For example,
the construction of a stud wall may be designated as a
nesting task named 'install wall #1' including other tasks
such as 'install dry wall', 'install studs', 'wall taping',
and 'erect wall' as sub-processes. A value that indicates
the relative tree view position of the task (in comparison
to the tree view position of other tasks and the task
hierarchy defined by IfcRelNests).
The task order information that is used for viewing
purposes is derived from the order defined by the
IfcRelNests relationship and thus is independent of
the logical task order defined through
IfcRelSequence. The hierarchy and order defined
through IfcRelNests enables to order the tasks in a
tree view or list view structure.
![]() |
Figure 14 — Task nesting relationships |
Time and duration use definition
Compared to previous IFC releases, basic task time
information (scheduled start time, scheduled finish
time, duration) is now directly attached to IfcTask
through the TaskTime attribute. Regular tasks are
defined through IfcTaskTime. Recurring tasks are
defined through IfcTaskTimeRecurring. In case a
regular task is derived from a recurring task both tasks
should be linked together through a IfcRelNests
relationship, where IfcRelNests.IsNestedBy points to
the recurring task and IfcRelNests.Nests points to
all regular tasks that have been derived from the recurring
task.
Assignment use definition
Occurrences of IfcTask may be assigned to an
IfcWorkControl (either a work plan or a work
schedule) through IfcRelAssignsToControl. From
IFC2x4 onwards it is suggested to use the 'summary task'
(root element of the task hierarchy that is required for
task management purposes) to assign all subtask to a work
plan or work schedule. Resources used by tasks are assigned
by IfcRelAssignsToProcess. Quantities of resources
consumed by the task are dealt with by defining the
IfcElementQuantity for the resource and not at the
instance of IfcTask. Please note that the
IfcRelAssignsTasks relationship class has been
removed in IFC2x4 and is no longer available.
An IfcTask may be assigned a Work Breakdown
Structure (WBS) code. A WBS code is dealt with as a
classification of task and is associated to a task
occurrence using the IfcRelAssociatesClassification
relationship class. As well as being to designate the code,
the classification structure of the IFC model also enables
the source of the work breakdown structure classification
to be identified.
Constraint use definition
Constraints may be applied to a task to indicate fixed task
duration, fixed start or fixed finish (see Figure 15). The relationship
IfcRelAssociatesConstraint is used where
RelatingConstraint points to an IfcMetric and
RelatedObjects includes the IfcTask.
IfcRelAssociatesConstraint.Name identifies the
attribute to be constrained using a period (""."") to
dereference; for example, ""TaskTime.ScheduleStart"" refers
to the ScheduleStart attribute on the
IfcTaskTime entity referenced on the TaskTime
attribute. The following attributes may be constrained:
-
'TaskTime.ScheduleDuration': Indicate fixed
duration of task with ConstraintGrade=HARD and
Benchmark=EQUALTO such that changes to an assigned
IfcConstructionResource.ResourceTime.ScheduleWork
should impact
IfcConstructionResource.ResourceTime.ScheduleUsage,
and vice-versa.
-
'TaskTime.ScheduleStart': Indicate constrained
start date with ConstraintGrade=HARD and Benchmark of
EQUALTO, GREATERTHANOREQUALTO, or LESSTHANOREQUALTO to
indicate ""must start on"", ""start no earlier than"" or
""start no later than"" respectively where
IfcMetric.DataValue indicates the specific
IfcDateTime. Use SOFT constraint having LESSTHAN
benchmark to indicate ""start as soon as possible"".
-
'TaskTime.ScheduleFinish': Indicate constrained
finish date with ConstraintGrade=HARD and Benchmark of
EQUALTO, GREATERTHANOREQUALTO, or LESSTHANOREQUALTO to
indicate ""must finish on"", ""finish no earlier than"" or
""finish no later than"" respectively where
IfcMetric.DateValue indicates the specific
IfcDateTime. Use SOFT constraint having
GREATERTHAN benchmark to indicate ""finish as late as
possible"".
A ""manual scheduled task"" is indicated with
ConstraintGrade=HARD and Benchmark=EQUALTO for both
TaskTime.ScheduleStart and
TaskTime.ScheduleFinish.
![]() |
Figure 15 — Task constraints |
Use Definition to represent other activities
The use definitions for IfcTask have been generalised to
represent other activities as well, including actitities
that had been defined by own entities in previous IFC
releases. This includes
- Order actions
- Move operations
IfcTask represents an order that might be carried
out by a Helpdesk acting the role of interface for the
organization between the facility user and the functional
requirement of fulfilling their needs. The actual task
represented by the IfcTask entity is turning a
request into an order and initiating the action that will
enable the order to be completed. The
IfcProjectOrder or one of its subtypes including
maintenance work order, is related to the IfcTask
using IfcRelAssignsToControl.
IfcTask can also be used to describe an activity
that moves people, groups within an organization or
complete organizations together with their associated
furniture and equipment from one place to another. It thus
replaces the previous IFC entity IfcMove. The functionality
is represented in IfcTask as follows:
- Move from: The place from which actors and their
associated equipment are moving.
Use IfcRelAssignsToProcess where
RelatingProcess points to the task and
RelatedObjects holds the location(s) from which to
move.
- Move to: The place to which actors and their
associated equipment are moving.
Use IfcRelAssignsToProduct where
RelatedObjects points to the task(s) and
RelatingProduct points to the location to which to
move.
- Punch list: A list of points concerning a move that
require attention.
Use LongDescription or else identify sub-tasks to
track punch list items individually via IfcRelNests.
"
2502;IfcProcedure;"
An IfcProcedure is a
logical set of actions to be taken in response to an event
or to cause an event to occur.
HISTORY New entity in IFC2x2
IFC2x4 CHANGE ProcedureType renamed to PredefinedType and made optional (upward compatible). Where rules WR1 and WR2 have been removed.
Use definitions
IfcProcedure is used to capture information about
stepped processes such as calibration, start/stop
procedures for equipment items, designated actions to take
in the event of an emergency etc. A procedure is not a
task, but may describe a set of tasks and their order of
occurrence in response to or to cause an event.
Type use definition
IfcProcedure defines the anticipated or actual
occurrence of any procedure; common information about
procedure types is handled by IfcProcedureType. The
IfcProcedureType (if present) may establish the
common type name, usage (or predefined) type, common nested
procedures (using IfcRelNests), common set of
properties, and common product assignment using
IfcRelAssignsToProduct. The IfcProcedureType
is attached using the
IfcRelDefinesByType.RelatingType objectified
relationship and is accessible by the inverse
IsTypedBy attribute.
Property set use definition
The property sets relating to IfcProcedure are
defined by IfcPropertySet and attached by the
IfcRelDefinesByProperties relationship. They are
accessible by the inverse IsDefinedBy relationship.
Such property sets may define procedure parameters. No
property sets for IfcProcedure are currently defined
by IFC.
Connectivity use definition
The relationship IfcRelSequence is used to indicate
control flow. An IfcProcedure as a successor to an
IfcEvent indicates that the procedure should be
performed in response to the event. An IfcProcedure
as a predecessor to an IfcEvent indicates that the
event should be trigerred following the procedure. As
procedures have arbitrary duration, the
IfcRelSequence.SequenceType attribute has no effect
on an IfcProcedure but still applies to the opposite
end of the relationship if IfcTask is used.
Composition use definition
IfcProcedure may be contained within an
IfcTask or IfcProcedure using the
IfcRelNests relationship. An IfcProcedure may
in turn nest other IfcProcedure or IfcEvent
entities. Such nesting indicates decomposed level of
detail.
Note that a particular type of IfcProcedure is a
caution, warning or other form of advisory note. Typically,
it is anticipated that such a procedure would be assigned
to the specific IfcProcess for which it gives advice
using IfcRelAssignsToProcess.
Assignment use definition
An IfcProcedure may be assigned to an
IfcWorkCalendar to indicate times when such
procedure may be performed using
IfcRelAssignsToControl; otherwise the effective
calendar is determined by the nearest IfcProcess
ancestor with a calendar assigned. Advisory notes should be
assigned to the specific IfcProcess for which it
gives advice using IfcRelAssignsToProcess.
For building operation scenarios, IfcProcedure may
be assigned to a product (IfcElement subtype) using
IfcRelAssignsToProduct to indicate a specific
product occurrence that performs the procedure. For
example, an IfcActuator may have a ""Close""
procedure. If the IfcProcedure is defined by an
IfcProcedureType and the IfcProcedureType is
assigned to a product type (using
IfcRelAssignsToProduct), then the
IfcProcedure must be assigned to one or more
occurrences of the specified product type using
IfcRelAssignsToProduct.
As shown in Figure 12, IfcProcedure does not restrict anything but
describes specific steps of how something should happen.
While a procedure does control/restrict in the sense of
indicating ""this is how the task should be performed"" by
nature of describing inner detail, this is not different than
parts of a product indicating ""this is how the parts should
be assembled"". Consequently, it doesn't restrict the outer
item as a whole but provides inner detail of the item.
![]() |
Figure 12 — Procedure relationships |
"
2516;IfcEvent;"
An IfcEvent is something
that happens that triggers an action or response.
HISTORY New entity in IFC2x4
Use definitions
IfcEvent is used to capture information about
particular things that happen or that may happen.
Particularly used in work plans (or process maps) they
identify e.g. a point at which a message containing
information may be issued or at which a rule or constraint
is invoked.
Type use definition
IfcEvent defines the anticipated or actual occurrence of
any event; common information about event types is handled
by IfcEventType. The IfcEventType (if present) may
establish the common type name, usage (or predefined) type,
common set of properties, and common product assignment
using IfcRelAssignsToProduct. The IfcEventType is attached
using the IfcRelDefinesByType.RelatingType objectified
relationship and is accessible by the inverse IsTypedBy
attribute.
Property set use definition
The property sets relating to IfcEvent are defined by
IfcPropertySet and attached by the
IfcRelDefinesByProperties relationship. They are accessible
by the inverse IsDefinedBy relationship. Such property sets
may define event parameters. No property sets for IfcEvent
are currently defined by IFC.
Connectivity use definition
The relationship IfcRelSequence is used to indicate control
flow. An IfcEvent as a predecessor
(IfcRelSequence.RelatingProcess) indicates that the
succeeding process (typically IfcProcedure or IfcTask) is
triggered in response to the event. An IfcEvent as a
successor (IfcRelSequence.RelatedProcess) indicates that
the completion of the preceeding process causes the event
to be triggered. As events have zero duration, the
IfcRelSequence.SequenceType attribute has no effect on an
IfcEvent but still applies to the opposite end of the
relationship if IfcTask is used.
Composition use definition
IfcEvent may be contained within an IfcTask using the
IfcRelNests relationship. The event is considered active
during the time period of the enclosing task (including any
assigned IfcWorkCalendar); that is such event may be
triggered within the task time period but not outside of
it. As an IfcEvent is considered to be atomic, no use is
anticipated for nesting processes inside the event.
Assignment use definition
An IfcEvent may be assigned to an IfcWorkCalendar to
indicate times when such event is active using
IfcRelAssignsToControl; otherwise the effective calendar is
determined by the nearest IfcProcess ancestor with a
calendar assigned.
For building operation scenarios, IfcEvent may be assigned
to a product (IfcElement subtype) using
IfcRelAssignsToProduct to indicate a specific product
occurrence that sources the event. For example, an
IfcSensor for a motion sensor may have a ""Motion Sensed""
event. If the IfcEvent is defined by an IfcEventType and
the IfcEventType is assigned to a product type (using
IfcRelAssignsToProduct), then the IfcEvent must be assigned
to one or more occurrences of the specified product type
using IfcRelAssignsToProduct.
"
2536;IfcWorkControl;"
An IfcWorkControl is an abstract supertype which captures information that is common to both IfcWorkPlan and IfcWorkSchedule.
HISTORY New class in IFC 2x
CHANGE IFC2x4 Corrected assignment of resources to work control in documentation. Assignment of tasks to work control updated based on changes of task time definitions and the introduction of a summary task. Identifier has been renamed (now Identification) and promoted to supertype IfcControl
A work control may have resources assigned to it, this is
handled by the IfcRelAssignsToControl relationship.
A work control should also define a context that gives
further information about its usage. If no special context
information is required then the IfcProject instance
as a global context should be used instead. An explicit
link between the work control and the IfcProject via
IfcRelDeclares should then be provided.
From IFC2x4 onwards the assignment of tasks to the work
control is handled by the IfcRelAssignsToControl
relationship. IfcRelAssignsTasks as used in previous
IFC releases has been deleted and can not be used any
longer. Another change in IFC2x4 is that it is not
necessary to assign each task to a work control as it is
regarded to be sufficient if the summary task (root task in
the task hierarchy defined through IfcRelNests
relationships) is assigned to a work control.
The attribute IfcWorkControl.Purpose is used to
define the purpose of either a work schedule or a work
plan. In the case of IfcWorkPlan, the purpose
attribute can be used to determine if the work plan is for
cost estimating, task scheduling or some other defined
purpose.
Property set use definition
The property sets relating to the IfcWorkControl are
defined by IfcPropertySet and attached by the
IfcRelDefinesByProperties relationship. It is
accessible by the inverse IsDefinedBy relationship.
The following property set definition specific to the
IfcWorkControl and its subtype are part of this IFC
release:
"
2546;IfcWorkPlan;"
An IfcWorkPlan represents work plans in a construction or a facilities management project.
HISTORY: New Entity in IFC 2.0
A work plan contains a set of work schedules for different
purposes (including construction and facilities
management). Contained work schedules are defined through
the IfcRelAggregates relationship. Through
inheritance from IfcWorkControl it is also possible
to define references to activities (for example, IfcTask)
and resources used in the work plan.
A work plan has information such as start date, finish
date, total free float, and so on. IfcWorkPlan can
also refer to the construction project represented by the
single IfcProject instance (please also check the
definition of IfcWorkControl).
Figure 18 shows the backbone structure of a work plan that
defines (1) contained work schedules through
IfcRelAggregates and (2), if not assigned otherwise
to contained work schedules, assigned tasks and resources
through IfcRelAssignsToControl.
![]() |
Figure 18 — Work plan relationships | |
"
2555;IfcWorkSchedule;"
An IfcWorkSchedule
represents a task schedule of a work plan, which in turn
can contain a set of schedules for different purposes.
HISTORY: New Entity in IFC
Release 2.0
Assignment Use Definition
An IfcWorkSchedule controls a set of tasks and
resources defined through IfcRelAssignsToControl.
Additionally, through the IfcWorkControl abstract
supertype, the actors creating the schedule can be
specified and schedule time information such as start time,
finish time, and total float of the schedule can also be
specified.
Declaration Use Definition
IfcWorkSchedule can reference a project (the
single IfcProject instance) via
IfcRelDeclares. The documents of the
IfcWorkSchedule can be referenced by the
IfcRelAssociatesDocuments relationship.
Composition Use Definition
A work schedule can include other work schedules as sub-items
through IfcRelNests relationship. If not included in
another work schedule it might be a part of a work plan
(IfcWorkPlan) defined through
IfcRelAggregates relationship.
Figure 19 shows the backbone structure of a work schedule
that defines (1) a context through IfcRelDeclares
(not necessarily the project) and (2) controls tasks
(typically the schedule summary task) and resources. Please
note that a work calendar shall be assigned to the summary
task and not the work schedule.
![]() |
Figure 19 — Work schedule relationships |
"
2564;IfcWorkCalendar;"
An IfcWorkCalendar defines working and non-working time periods for tasks and resources. It enables to define both specific time periods, such as from 7:00 till 12:00 on 25th August 2009, as well as repetitive time periods based on frequently used recurrence patterns, such as each Monday from 7:00 till 12:00 between 1st March 2009 and 31st December 2009.
HISTORY New entity in IFC2x4.
A work calendar is a subtype of IfcControl and thus inherits the feature for controlling other objects through IfcRelAssignsToControl, which is used to define a work calendar for tasks (IfcTask) and resources (IfcResource). It also inherits a name and description attribute, whereas a name shall be given and a description may be given as an indication of its content and usage.
The definition of time periods can be derived from a base calendar and/or modified/defined by a set of working times and non-working exception times. All time periods defined by IfcWorkCalendar.ExceptionTimes override the time periods inherited from the base calendar (base calendar is defined as the next applicable calendar for the task or resource). Thus, exception times replace the working times from the base calendar.
The base calendar of a work calendar is defined by IfcRelAssignsToControl, where IfcRelAssignsToControl.RelatingControl is linked with the base calendar and IfcRelAssignsToControl.RelatedObjects is linked with work calendars that are derived from the base calendar. Although not restricted by the IfcRelAssignsToControl relationship it is only allowed to have one base calendar.
Figure 17 shows the definition of a work calendar, which is defined by a set of work times and exception times. The work times are defined as recurring patterns with optional boundaries (applying from and/or to a specific date). The shown example defines a simple work calendar with working times Monday to Thursday 8:00 to 12:00 and 13:00 to 17:00, Friday 8:00 to 14:00 and as exception every 1st Monday in a month the work starts one hour later - i.e. the working time on every 1st Monday in a month is overriden to be 9:00 to 12:00 and 13:00 to 17:00. Both the working time and the exception time is valid for the period of 01.09.2010 till 30.08.2011.
![]() |
Figure 17 — Work calendar instantiation |
"
2575;IfcRelSequence;"
IfcRelSequence is a
sequential relationship between processes where one process
must occur before the other in time and where the timing of
the relationship may be described as a type of sequence.
The relating process
(IfcRelSequence.RelatingProcess) is considered to be
the predecessor in the relationship (has precedence) whilst
the related process (IfcRelSequence.RelatedProcess)
is the successor.
IfcRelSequence is defined as one-to-one
relationship; therefore it assigns one predecessor to one
successor.
HISTORY New entity in IFC 1.0.
IFC2x4 CHANGE Relocated to IfcProcessExtension schema.
TimeLag and SequenceType made optional.
USERDEFINED added to the IfcSequenceType
enumeration. UserDefinedSequenceType attribute
added. WHERE rule controlling use of the USERDEFINED
enumeration added.
Use definitions
IfcRelSequence is used to describe the logical
sequence relationship that exists between two processes.
This logical relationship identifies that there is a
predecessor or relating process and a successor or related
process. In IFC, there may be one predecessor and one
successor in the relationship. Many occurrences of
IfcRelSequence may exist to describe the sequence
relationships of a predecessor task with many successor
tasks or of many predecessor tasks with one successor task,
thus enabling a m:n sequence relationship between tasks.
Please note that sequence relationships always should stay
within the limits of a directed, non-cyclic graph.
A sequence type may be set for a sequence. For tasks
assigned to a work schedule, it is expected that the
sequence type will be asserted. For a process map, where
the sequence relationship between processes is simply a
logical flow, it need not be asserted.
A time lag may be assigned to a sequence, and the sequence
type defines the way in which the time lag applies to the
sequence either as a ratio or percentage of time duration
(e.g. start successor task when predecessor is 50%
complete) or as a time measure (e.g. start successor task 1
week after commencement of the predecessor task). Care
should be used when assigning a time lag to a sequence
depending on the setting of the sequence type since there
is no checking that the time lag value is in keeping with
the sequence type set.
"
2590;IfcTaskType;"
An IfcTaskType defines a
particular type of task that may be specified for use
within a work control.
HISTORY New entity in IFC2x4
An IfcTaskType provides for all forms of types of
task that may be specified.
Usage of IfcTaskType defines the parameters for one
or more occurrences of IfcTask. Parameters may be
specified through property sets that may be enumerated in
the IfcTaskTypeEnum data type or through explict
attributes of IfcTaskType. Task occurrences
(IfcTask entities) are linked to the task type
through the IfcRelDefinesByType relationship.
Composition use definition
IfcTaskType may nest other IfcTaskType or
IfcTask entities using the IfcRelNests
relationship. Such nesting indicates decomposed level of
detail. Nesting of IfcTask entities is used if a
task type shall be detailed by a sequence of tasks or if
there is a need to include additional time information such
as the duration of subtasks. Please note that
IfcTask entities being contained within an
IfcTaskType are linked with their task occurrences
via IfcRelDefinesByObject relationships. It is also
possible to define a task type for these IfcTask
entities via IfcRelDefinesByType relationships. For
further information please see the documentation of
IfcRelDefinesByObject.
Figure 16 shows the definition of a task type that is part
of a task template library. Please note that in this
example the task type is further subdivided into tasks that
define task times (for example, duration) and/or a task sequence.
![]() |
Figure 16 — Task type relationships |
"
2594;IfcProcedureType;"
An IfcProcedureType defines a particular type of procedure that may be specified.
HISTORY New entity in IFC2x4
An IfcProcedureType provides for all forms of types of procedure that may be specified.
Usage of IfcProcedureType defines the parameters for
one or more occurrences of IfcProcedure. Parameters
may be specified through property sets that may be
enumerated in the IfcProcedureTypeEnum data type or
through explict attributes of IfcProcedure. Procedure occurrences
(IfcProcedure entities) are linked to the procedure type
through the IfcRelDefinesByType relationship.
"
2597;IfcEventType;"
An IfcEventType defines a particular type of event that may be specified.
HISTORY New entity in IFC2x4
An IfcEventType provides for all forms of types of event that may be specified.
Usage of IfcEventType defines the parameters for one or more occurrences of IfcEvent. Parameters may be specified through property sets that may be enumerated in the IfcEventTypeEnum data type or through explicit attributes of IfcEvent. Event occurrences (IfcEvent entities) are linked to the event type through the IfcRelDefinesByType relationship.
"
2604;IfcCostSchedule;"
An IfcCostSchedule brings together instances of IfcCostItem either for the purpose of identifying purely cost information as in an estimate for constructions costs or for including cost information within another presentation form such as a work order.
HISTORY New Entity in IFC Release 2.0. Modified in IFC 2x2
IFC2x4 CHANGE Attribute 'ID' changed to Identification and promoted to supertype IfcControl, PredefinedType made optional, attributes PreparedBy, SubmittedBy, TargetUsers removed.
Declaration Use Definition
The IfcCostSchedule may be declared within the project using the IfcRelDeclares relationship where RelatingContext refers to the single IfcProject and RelatedDefinitions contains the IfcCostSchedule. Alternatively, if the IfcCostSchedule is aggregated within another IfcControl object, then it shall not have a direct declaration relationship (whereas the containing object may have a declaration relationship).
Assignment Use Definition
The IfcCostSchedule may be assigned to the following entities using relationships as indicated:
The IfcCostSchedule may have assignments of its own using the IfcRelAssignsToControl relationship where RelatingControl refers to the IfcCostSchedule and RelatedObjects contains one or more objects of the following types:
- IfcCostItem: Indicates costs published within this cost schedule, typically a single root cost item forming a hierarchy of nested cost items.
Classification Use Definition
Classifications may be applied using IfcRelAssociatesClassification where RelatedObjects contains the IfcCostSchedule and RelatingClassification refers to an IfcClassification or IfcClassificationReference.
- IfcClassification: Classifications to be used for cost items within the cost schedule.
Approval Use Definition
Approvals may be associated to indicate the status of acceptance or rejection using the IfcRelAssociatesApproval relationship where RelatingApproval refers to an IfcApproval and RelatedObjects contains the IfcCostSchedule. Approvals may be split into sub-approvals using IfcApprovalRelationship to track approval status separately for each party where RelatingApproval refers to the higher-level approval and RelatedApprovals contains one or more lower-level approvals. The hierarchy of approvals implies sequencing such that a higher-level approval is not executed until all of its lower-level approvals have been accepted.
"
2619;IfcProjectOrder;"
A project order is a directive to purchase products and/or perform work, such as for construction or facilities management.
Project orders are typically formal contracts between two organizations, where cost and time information may be rigid or flexible according to contained schedule types and constraints.
HISTORY New entity in IFC 2.0
IFC2x4 CHANGE Attribute 'ID' changed to Identification and promoted to supertype IfcControl. Attribute 'LongDescription' added.
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship. They are accessible by the IsDefinedBy inverse attribute. Refer to the documentation at the supertype IfcControl and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity according to the PredefinedType attribute:
Declaration Use Definition
The IfcProjectOrder may be declared within the project using the IfcRelDeclares relationship where RelatingContext refers to the single IfcProject and RelatedDefinitions contains the IfcProjectOrder. Alternatively, if the IfcProjectOrder is aggregated within an IfcWorkPlan, then it shall not have a direct declaration relationship (whereas the containing work plan may have a declaration relationship).
Composition Use Definition
As shown in Figure 160, an IfcProjectOrder may be aggregated into components using IfcRelAggregates where RelatingObject refers to the enclosing IfcProjectOrder and RelatedObjects contains one or more components. Aggregation use is defined for the following predefined types:
- (All Types): May contain IfcCostSchedule components. A cost schedule may indicate costs and quantities where the cost schedule type may designate whether rates and/or quantities are estimated or final. Such cost schedule may have assigned cost items indicating detail, where each cost item may have assigned products, processes, or resources.
- WORKORDER: May contain IfcWorkSchedule components. A work schedule may indicate tasks and scheduled times where the work schedule type may designate whether tasks and/or times are planned or actual. Such work schedule may have assigned tasks indicating detail, where tasks may be assigned to products and may have assigned resources.
The IfcProjectOrder may be nested into sub-items using IfcRelNests where RelatingObject refers to the enclosing IfcProjectOrder and RelatedObjects contains one or more sub-items. Nesting use is defined for the following predefined types:
- WORKORDER: May contain IfcProjectOrder sub-items having PredefinedType CHANGEORDER. A work order may be nested into change orders to indicate contract ammendment, in order of issue.
![]() |
Figure 161 — Project order composition |
Assignment Use Definition
As shown in Figure 161, an IfcProjectOrder may be assigned to the following entities using relationships as indicated:
The IfcProjectOrder may have assignments of its own using the IfcRelAssignsToControl relationship where RelatingControl refers to the IfcProjectOrder and RelatedObjects contains one or more objects of the following types:
- IfcActor: Organization(s) contracted to fulfill the order, typically a single contractor, subcontractor, or supplier.
![]() |
Figure 162 — Project order assignment |
Approval Use Definition
Approvals may be associated to indicate the status of acceptance or rejection using the IfcRelAssociatesApproval relationship where RelatingApproval refers to an IfcApproval and RelatedObjects contains the IfcProjectOrder. Approvals may be split into sub-approvals using IfcApprovalRelationship to track approval status separately for each party where RelatingApproval refers to the higher-level approval and RelatedApprovals contains one or more lower-level approvals. The hierarchy of approvals implies sequencing such that a higher-level approval is not executed until all of its lower-level approvals have been accepted.
"
2631;IfcCostItem;"
An IfcCostItem describes a cost or financial value together with descriptive information that describes its context in a form that enables it to be used within a cost schedule. An IfcCostItem can be used to represent the cost of goods and services, the execution of works by a process, lifecycle cost and more.
Each instance of IfcCostItem may have a name and a description. Depending on the use for which the cost is intended, these values should be asserted on the basis of agreement. For instance, the Name attribute could be used to provide a common value that enables distinct instances to be brought together in a nesting arrangement (see below) while the Description attribute may be used to provide text used for item description in a costing schedule.
An IfcCostItem can link one or many IfcCostValue's representing a unit cost, total cost, or a unit cost with one or many quantities used to generate the total cost. The quantities can be given as individual quantities, or those quantities are provided as element quantities by one or many building elements. The IfcCostValue.CostType attribute indicates the category of cost, which may be used to present the value in a particular column. For nested cost items (having IfcRelNests relationship), IfcCostValue.CostType is significant such that IfcCostValue.AppliedValue is calculated as the sum of all nested costs having the same IfcCostValue.CostType or if set to an asterisk ('*'), then the sum of all nested costs of all cost types. An IfcCostValue may represent an original value or a value derived from formulas using IfcAppliedValueRelationship. For example, taxes may be calculated as a percentage of a subtotal.
HISTORY New Entity in IFC Release 2.0.
IFC2x4 CHANGE Attribute PredefinedType, CostValues, and CostQuantities added.
Classification Use Definition
Instances of IfcCostItem are used for cost estimates, budgets, and other forms, where a variety of identification codes are used extensively to identify the meaning of the cost. Examples include project phase codes, CSI codes, takeoff sequence numbers, and cost accounts. The model allows for all classes that are ultimately subtypes of IfcObject to inherit the ability to have one or more instances of IfcClassificationReference to be assigned. Where identification codes are required, the generic IfcRelAssociatesClassification facility should be used.
Composition Use Definition
An IfcCostItem can nest other instances of IfcCostItem through its relationships to IfcRelNests. This can be used to enable the development of complex groups of costs as may be found in cost schedules through to pages, sections and complete cost schedules.
There is always a summary cost item as the root item of the tree representing the cost item nesting. Subsequent instances of IfcCostItem are assigned to the summary cost item using IfcRelNests. The summary cost item itself is assigned to IfcCostSchedule through the IfcRelAssignsToControl relationship.
Figure 157 illustrates a cost item composition used for a cost schedule. Each line item has a quantity and separate unit costs where IfcCostValue.CostType indicates the category of cost. The summary item has a hierarchy of costs calculated according to IfcAppliedValueRelationship.ArithmeticOperator, where IfcCostValue.CostType identifies the category to be totalled. The Tax component has IfcCostValue.CostType set to 'Material' which indicates it is the sum of all nested values of the 'Material' category ($3 x 3000 + $118 x 100 = $20800). The Subtotal component has IfcCostValue.CostType set to an asterisk ('*') which indicates it is the sum of all nested values of all categories.
![]() |
Figure 157 — Cost composition |
Assignment Use Definition
An IfcCostItem can be calculated based on quantities from objects through its relationship to IfcRelAssignsToControl.
For quantity-based costing, IfcElement, IfcTask, or IfcResource occurrence subtypes may be used. Multiple elements may be assigned of the same or different types, using IfcPhysicalQuantity entities defined at each object. Each IfcPhysicalQuantity type must be identical (for example, all values are IfcAreaQuantity) such that they can be added together.
For rate-based costing (specifically for IfcCostScheduleTypeEnum.SCHEDULEOFRATES), a single IfcTypeProduct, IfcTypeProcess, or IfcTypeResource subtype may be used to reflect rates for occurrences of such types. This enables the possibility to generate a quantity-based cost schedule for occurrences based on types with rate-based cost schedules.
IfcRelAssignsToControl is also used in the opposite direction to link the root IfcCostItem to an IfcCostSchedule where RelatingControl is the IfcCostSchedule.
Figure 158 illustrates cost item assignment derived from building elements. The IfcRelAssignsToControl relationship indicates building elements for which quantities are derived. Not shown, costs may also be derived from building elements by traversing assignment relationships from the assigned IfcProduct to IfcProcess to IfcResource, where all costs ultimately originate at resources. It is also possible for cost items to have assignments from processes or resources directly.
![]() |
Figure 168 — Cost assignment |
"
2638;IfcPermit;"
A permit is a permission to perform work in places and on artifacts where regulatory, security or other access restrictions apply.
HISTORY New entity in IFC2x2
IFC2x4 CHANGE PermitID renamed to Identification and promoted to supertype IfcControl, Attributes PredefinedType, Status, and LongDescription added.
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship. They are accessible by the IsDefinedBy inverse attribute. Refer to the documentation at the supertype IfcControl and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Declaration Use Definition
The IfcPermit may be declared within the project using the IfcRelDeclares relationship where RelatingContext refers to the single IfcProject and RelatedDefinitions contains the IfcPermit. Alternatively, if the IfcPermit is aggregated within an IfcWorkPlan, then it shall not have a direct declaration relationship (whereas the containing work plan may have a declaration relationship).
Composition Use Definition
The IfcPermit may be aggregated into components using IfcRelAggregates where RelatingObject refers to the enclosing IfcPermit and RelatedObjects contains one or more components. Aggregation use is defined for the following predefined types:
- ACCESS: May contain IfcWorkCalendar components. A work calendar may indicate the time period of the permit and allowed times when work may be performed. Such work calendar may have assigned resources indicating equipment or labor permitted at various times.
- WORK: May contain IfcWorkSchedule components. A work schedule may indicate tasks and scheduled times where the work schedule type may designate whether tasks and/or times are planned or actual. Such work schedule may have assigned tasks indicating detail, where tasks may be assigned to products and may have assigned resources.
As shown in Figure 159, an IfcPermit may be nested into sub-items using IfcRelNests where RelatingObject refers to the enclosing IfcPermit and RelatedObjects contains one or more sub-items. Nesting use is defined for the following predefined types:
- (All Types): May contain IfcPermit sub-items. A permit may be nested to indicate permit ammendments, in order of issue.
![]() |
Figure 159 — Permit composition |
Assignment Use Definition
As shown in Figure 160, an IfcPermit may be assigned to the following entities using relationships as indicated:
The IfcPermit may have assignments of its own using the IfcRelAssignsToControl relationship where RelatingControl refers to the IfcPermit and RelatedObjects contains one or more objects of the following types:
- IfcActor: Organization(s) bound to the permit, typically a single contractor.
![]() |
Figure 160 — Permit assignment |
Approval Use Definition
Approvals may be associated to indicate the status of acceptance or rejection using the IfcRelAssociatesApproval relationship where RelatingApproval refers to an IfcApproval and RelatedObjects contains the IfcPermit. Approvals may be split into sub-approvals using IfcApprovalRelationship to track approval status separately for each party where RelatingApproval refers to the higher-level approval and RelatedApprovals contains one or more lower-level approvals. The hierarchy of approvals implies sequencing such that a higher-level approval is not executed until all of its lower-level approvals have been accepted.
"
2648;IfcActionRequest;"
A request is the act or instance of asking for something, such as a request for information, bid submission, or performance of work.
Requests may take many forms depending on the need including fault reports for maintenance, requests for small works, and purchase requests (where these are to be made through a help desk or buying function).
HISTORY: New entity in IFC2x2
IFC2x4 CHANGE RequestID renamed to Identification and promoted to supertype IfcControl, attributes PredefinedType, Status, and LongDescription added.
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship. They are accessible by the IsDefinedBy inverse attribute. Refer to the documentation at the supertype IfcControl and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Declaration Use Definition
The IfcActionRequest may be declared within the project using the IfcRelDeclares relationship where RelatingContext refers to the single IfcProject and RelatedDefinitions contains the IfcActionRequest. Alternatively, if the IfcActionRequest is aggregated within an IfcWorkPlan, then it shall not have a direct declaration relationship (whereas the containing work plan may have a declaration relationship).
Composition Use Definition
As shown in Figure 155, an IfcActionRequest may be aggregated into components using IfcRelAggregates where RelatingObject refers to the enclosing IfcActionRequest and RelatedObjects contains one or more components. Aggregation use is defined for the following predefined types:
- (All Types): May contain IfcCostSchedule components. A cost schedule may indicate costs and quantities where the cost schedule type may designate whether rates and/or quantities are estimated or final. Such cost schedule may have assigned cost items indicating detail, where each cost item may have assigned products, processes, or resources.
The IfcActionRequest may be nested into sub-items using IfcRelNests where RelatingObject refers to the enclosing IfcActionRequest and RelatedObjects contains one or more sub-items. Nesting use is defined for the following predefined types:
- (All Types): May contain IfcActionRequest sub-items. A request may be nested into follow-up requests, in order of issue.
![]() |
Figure 155 — Action request composition |
Assignment Use Definition
As shown in Figure 156, an IfcActionRequest may be assigned to the following entities using relationships as indicated:
The IfcActionRequest may have assignments of its own using the IfcRelAssignsToControl relationship where RelatingControl refers to the IfcActionRequest and RelatedObjects contains one or more objects of the following types:
- IfcActor: Person or organization(s) fulfilling the request such as a facilities manager or contractor.
![]() |
Figure 156 — Action request assignment |
Approval Use Definition
Approvals may be associated to indicate the status of acceptance or rejection using the IfcRelAssociatesApproval relationship where RelatingApproval refers to an IfcApproval and RelatedObjects contains the IfcActionRequest. Approvals may be split into sub-approvals using IfcApprovalRelationship to track approval status separately for each party where RelatingApproval refers to the higher-level approval and RelatedApprovals contains one or more lower-level approvals. The hierarchy of approvals implies sequencing such that a higher-level approval is not executed until all of its lower-level approvals have been accepted.
"
2661;IfcConstructionResource;"
IfcConstructionResource is an abstract generalization of the different resources used in
construction projects, mainly labor, material, equipment and product resources, plus subcontracted resources and aggregations such as a crew resource.
A resource represents ""use of something"" and does not necessarily correspond to a single item such as a person or vehicle, but
represents a pool of items having limited availability such as general labor or an equipment fleet. A resource can represent either a generic resource pool (not having any task assignment) or a task-specific resource allocation (having an IfcTask
assignment).
HISTORY New entity in IFC2x2.
IFC2x4 CHANGE Modified in to promote ResourceIdentifer and ResourceGroup (renamed to LongDescription) to supertype IfcResource and add attributes as described.
Type use definition
IfcConstructionResource defines the occurrence of any construction resource; common information about construction resource types is handled by IfcConstructionResourceType. The IfcConstructionResourceType (if present) may establish the common type name, common properties, common cost rates, and common productivities applied to specific task types. The IfcConstructionResourceType is attached using the IfcRelDefinesByType.RelatingType objectified relationship and is accessible by the inverse IsTypedBy attribute as shown in Figure 186.
The resource type may provide shared productivity and cost information, allowing tasks and resources to be selected according to lowest cost and/or shortest duration. Given an IfcProduct of a particular IfcTypeProduct type, an IfcTypeProcess may be selected from those assigned to the product type using IfcRelAssignsToProduct, and an IfcTypeResource may be selected from those assigned to the process type using IfcRelAssignsToProcess. Then IfcTask and IfcConstructionResource occurrences may be instantiated from the type definitions, applying productivitity and rate information to assigned quantities to calculate ResourceTime.ScheduleWork. Task durations can then be calculated by dividing ResourceTime.ScheduleWork by ResourceTime.ScheduleUsage.
![]() |
Figure 186 — Construction resource type use |
Composition use definition
Resources may be decomposed into allocation pools using the IfcRelNests relationship as shown in Figure 187. For example, an IfcLaborResource for ""Electrician"" may be decomposed into three task-specific IfcLaborResource objects: ""Electrical Rough-in"", ""First Floor Circuits"", and ""Second Floor Circuits"". Both relating and related sides may represent the same ResourceTime.ScheduleUsage quantity (for example, 6 workers time-shared), or the related side may break out ResourceTime.ScheduleUsage quantities for reserved use (for example, 4 workers and 2 workers).
A common scenario is two nesting levels where the first-level resources have no task assignments; while second-level resources have specific task assignments indicating that the resource is subdivided into allocations for specific tasks. While the model allows unlimited nesting of resources, implementer agreements may restrict to two nesting levels with task assignments specifically at the second level.
![]() |
Figure 187 — Construction resource composition use |
Declaration use definition
A root-level resource (specifically IfcCrewResource or IfcSubContractResource) is declared within the project by IfcRelDeclares where RelatingContext refers to the single IfcProject and RelatedObjects refers to one or more IfcConstructionResource, and other root-level objects within the project.
Assignment use definition
A resource may be assigned to an actor by IfcRelAssignsToActor where RelatingActor refers to an IfcActor and RelatedObjects refers to one or more IfcConstructionResource or other objects. Such relationship indicates the actor responsible for allocating the resource such as partitioning into task-specific allocations, delegating to other actors, and/or scheduling over time. Note that this assignment does not indicate the person or organization performing the work; that is indicated by IfcRelAssignsToResource. The actor responsible for the resource may or may not be the same as any actor(s) performing work.
A resource may be assigned to a control by IfcRelAssignsToControl where RelatingProduct refers to an IfcControl and RelatedObjects refers to one or more IfcConstructionResource or other objects. Most commonly an IfcWorkCalendar is assigned indicating availability of the resource, where such calendar is nested within a base calendar or an IfcWorkPlan which in turn is assigned to the IfcProject.
A resource may be assigned to a group by IfcRelAssignsToGroup where RelatingGroup refers to an IfcGroup and RelatedObjects refers to one or more IfcConstructionResource or other objects. Most commonly an IfcAsset is assigned indicating the asset to be tracked, where such asset is nested within an IfcInventory which in turn is assigned to the IfcProject.
A resource may be assigned to a product by IfcRelAssignsToProduct where RelatingProduct refers to an IfcProduct and RelatedObjects refers to one or more IfcConstructionResource or other objects. Most commonly an IfcElement subtype is assigned indicating the product to be constructed, where such product is connected to a spatial
structure which in turn is aggregated within the IfcProject.
A resource may be assigned to a process by IfcRelAssignsToProcess where RelatingProcess refers to an IfcProcess and RelatedObjects refers to one or more IfcConstructionResource or other objects. Most commonly an IfcTask is assigned indicating the task to be performed by the resource, where such task is nested within a summary task which in turn is assigned to the IfcProject.
A resource may have assignments of other objects using IfcRelAssignsToResource where RelatingResource refers to the IfcConstructionResource and RelatedObjects refers to one or more objects such as IfcActor or IfcProduct subtypes. This relationship indicates specific objects assigned to fulfill resource usage.
Figure 188 illustrates resource assignment.
![]() |
Figure 188 — Construction resource assignment use |
Constraint use definition
Constraints may be applied to a resource to indicate fixed work (such as total person-hours) or fixed usage (such as simultaneous workers). The relationship IfcRelAssociatesConstraint is used where RelatingConstraint points to an IfcMetric and RelatedObjects includes the IfcConstructionResource as shown in Figure 189. IfcRelAssociatesConstraint.Name identifies the attribute to be constrained using a period (""."") to dereference; for example, ""ResourceTime.ScheduleWork"" refers to the ScheduleWork attribute on the IfcResourceTime entity referenced on the ResourceTime attribute. The following attributes may be constrained:
- 'ResourceTime.ScheduleUsage': Indicate fixed usage (e.g.
simultaneous workers) with ConstraintGrade=HARD and
Benchmark=EQUALTO such that changes to
ResourceTime.ScheduleWork should impact the assigned
IfcTask.TaskTime.ScheduleDuration and vice-versa
- 'ResourceTime.ScheduleWork': Indicate fixed work (e.g.
total person-hours) with ConstraintGrade=HARD and
Benchmark=EQUALTO such that changes to
ResourceTime.ScheduleUsage should impact the assigned
IfcTask.TaskTime.ScheduleDuration and vice-versa.
![]() |
Figure 189 — Construction resource constraint use |
Time series use definition
Time series may be applied to a resource to indicate the break-out of attribute values over time. The relationship IfcRelAssociatesTimeSeries is used where RelatingTimeSeries points to an IfcTimeSeries (either IfcRegularTimeSeries or IfcIrregularTimeSeries) and RelatedObjects includes the IfcConstructionResource as shown in Figure 190. IfcRelAssociatesTimeSeries.Name identifies the attribute to be constrained using a period (""."") to dereference; for example, ""ResourceTime.ScheduleWork"" refers to the ScheduleWork attribute on the IfcResourceTime entity referenced on the ResourceTime attribute. Refer to attribute descriptions on IfcResourceTime for attribute-specific usage.
Each IfcTimeSeriesValue indicates a LIST of values, where the sequence of the value corresponds to the IfcCostValue at IfcConstructionResource.CostRatesConsumed. For example, if CostRatesConsumed has two IfcCostValue items in the LIST, ""Standard"" and ""Overtime"", then IfcTimeSeriesValue(IfcDuration('T8H0M0S'),IfcDuration('T2H0M0S')) would indicate 8 hours at Standard rate and 2 hours at Overtime rate. If the list of values at IfcTimeSeriesValue.ListValues is less than the size of CostRatesConsumed, then subsequent values are considered to be zero.
![]() |
Figure 190 — Construction resource time series use |
Document use definition
Documents may be published for work plans consisting of schedules, calendars, tasks, and resources. The relationship IfcRelAssociatesDocument may be used to preserve mappings to such document where RelatingDocument points to an IfcDocumentReference and RelatedObjects includes the IfcConstructionResource as shown in Figure 191.
IfcDocumentReference.ItemReference identifies the resource within the scope of the document, such as an integer or guid. The IfcDocumentReference.ReferencedDocument corresponds to the document which is uniquely identified by IfcDocumentInformation.DocumentId and/or IfcDocumentInformation.PublicationLocation. Such document mapping allows items in the document to be updated from the building information model and vice-versa.
![]() |
Figure 191 — Construction resource document use |
Baseline use definition
A resource may have any number of baselines defined using the relationship IfcRelDefinesByObject where RelatingObject is the ""current"" resource and RelatedObjects consists of multiple ""baseline"" resources, each representing a copy of the resource as it existed at an earlier point in time as shown in Figure 192. Each baseline IfcConstructionResource is identified by its nested IfcRelAssignsToControl relationship to an IfcWorkSchedule having
PredefinedType=BASELINE, IfcWorkSchedule.CreationDate indicating the date of the baseline, and
IfcWorkSchedule.Name indicating the name of the baseline.
![]() |
Figure 192 — Construction resource baseline use |
"
2675;IfcConstructionEquipmentResource;"
IfcConstructionEquipmentResource is usage of construction equipment to assist in the performance of construction. Construction Equipment resources are wholly or partially consumed or occupied in the performance of construction.
HISTORY: New Entity in IFC Release 2.0. Base type and documentation extended in IFC2x4.
Occurrences of IfcConstructionEquipmentResource are products that are used as resources to assist the process of construction. More specifically, they are products that are standalone items brought to a project to fulfil a particular purpose. Examples might be a tower crane or other mobile crane, a screwing machine, a lifting hoist etc. They are explicitly instances of IfcProduct and may be drawn from various of the subtype, for instance IfcTransportElement, IfcDiscreteAccessory, IfcProxy (for particular cases where more precise usage details are not available).
A product that is used as an IfcConstructionEquipmentResource is referenced using the IfcRelAssignsToResource.RelatedObjects relationship.
Use definitions for composition, assignment, constraints, time series, and baselines are described at the base type IfcConstructionResource.
Type use definition
IfcConstructionEquipmentResource defines the occurrence of any construction equipment resource; common information about construction equipment resource types is handled by IfcConstructionEquipmentResourceType. The IfcConstructionEquipmentResourceType (if present) may establish the common type name, common properties, and common productivities for various task types using IfcRelAssignsToProcess. The IfcConstructionEquipmentResourceType is attached using the IfcRelDefinesByType.RelatingType objectified relationship and is accessible by the inverse IsTypedBy attribute.
Quantity use definition
The quantities relating to the IfcConstructionEquipmentResource are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship. It is accessible by the inverse IsDefinedBy relationship. The following base quantities are defined and should be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'. Other quantities can be defined being subjected to local standard of measurement with another string value assigned to Name and a value provided for MethodOfMeasurement.
Assignment use definition
In addition to assignments specified at the base class IfcConstructionResource, a construction equipment resource may have assignments of its own using IfcRelAssignsToResource where RelatingResource refers to the IfcConstructionEquipmentResource and RelatedObjects contains one or more IfcProduct subtypes as shown in Figure 183. Such relationship indicates the equipment used as input for the resource. Such products are not contained within a building structure but are referenced within a construction spatial zone, specifically IfcSpatialZone with PredefinedType=CONSTRUCTION, which is aggregated within the IfcProject. There may be multiple chains of production such that the assigned equipment may have their own task and resource assignments for assembling such equipment.
![]() |
Figure 183 — Construction equipment resource assignment |
"
2689;IfcLaborResource;"
An IfcLaborResource is used in construction with particular skills or crafts required to perform certain types of construction or management related work.
HISTORY: New Entity in IFC Release 2.0. Base type and documentation extended in IFC 2x4.
IFC2x4 CHANGE: The attribute Skillset has been deleted; use LongDescription to describe the skillset.
The purpose of an IfcLaborResource is to identify a skillset that may be required or used. The skillset identified may be (for instance) chargehand, foreman, labourer, plumbers mate etc. and provides a designation of a particular level of skill. It can be used to identify the generic type of labor resource that is required for a purpose without having to be specific about the actor (person or organization) providing the resource occurrence. It may be particularly useful when creating an overall plan for a process or processes. For instance, within maintenance or work planning there may be a known task that needs to be done which is planned to require a 'chargehand pipe fitter'. There may be several such labor resources available and so the need to identify which will be used is not necessary at the planning stage.
At a later stage, individual actors can be determined for the labor resources. This is achieved through specifiying the actor through IfcActor. The actor is then identified as the labour resource occurrence through the IfcRelAssignsToResource.RelatedResource attribute. The IfcLaborResource provides the IfcRelAssignsToResource.RelatingResource attribute.
Use definitions for composition, assignment, constraints, time series, and baselines are described at the base type IfcConstructionResource.
Type use definition
IfcLaborResource defines the occurrence of any labor resource; common information about labor resource types is handled by IfcLaborResourceType. The IfcLaborResourceType (if present) may establish the common type name, common properties, common productivities for various task types using IfcRelAssignsToProcess. The IfcLaborResourceType is attached using the IfcRelDefinesByType.RelatingType objectified relationship and is accessible by the inverse IsTypedBy attribute.
Quantity use definition
The quantities relating to the IfcLaborResource are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship. It is accessible by the inverse IsDefinedBy relationship. The following base quantities are defined and should be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'. Other quantities can be defined being subjected to local standard of measurement with another string value assigned to Name and a value provided for MethodOfMeasurement.
Assignment use definition
In addition to assignments specified at the base class IfcConstructionResource, a labor resource may have assignments of its own using IfcRelAssignsToResource where RelatingResource refers to the IfcLaborResource and RelatedObjects contains one or more IfcActor subtypes as shown in Figure 194. Such relationship indicates the specific people used as input for the resource. Such actors are nested according to organizational structure with the root organization assigned to the IfcProject. The IfcActor entity is used to represent the people or organizations.
![]() |
Figure 194 — Labor resource assignment use |
"
2714;IfcCrewResource;"
IfcCrewResource represents a collection of internal resources used in construction processes.
HISTORY: New Entity in IFC Release 2.0. Base type and documentation extended in IFC2x4
Identification of people and equipment of a crew is achieved through their specification at the level of the component. Therefore, knowing which persons are within a crew is achieved through identifying the persons assigned to each IfcLaborResource within the IfcCrewResource. Similarly, identifying that a screwing machine for pipe fitting forms part of the crew is achieved by relating an appropriate instance of IfcElementComponent to the IfcConstructionEquipmentResource forming an element of the IfcCrewResource.
Use definitions for composition, assignment, constraints, time series, and baselines are described at the base type IfcConstructionResource.
Type use definition
IfcCrewResource defines the occurrence of any crew resource; common information about crew resource types is handled by IfcCrewResourceType. The IfcCrewResourceType (if present) may establish the common type name, common properties, and common productivities for various task types using IfcRelAssignsToProcess. The IfcCrewResourceType is attached using the IfcRelDefinesByType.RelatingType objectified relationship and is accessible by the inverse IsTypedBy attribute.
"
2722;IfcSubContractResource;"
IfcSubContractResource is a construction resource needed in a construction process that represents a sub-contractor.
HISTORY: New Entity in IFC Release 2.0. Base type and documentation extended in IFC 2x4.
IFC2x4 CHANGE: The attribute SubContractor has been deleted; use IfcRelAssignsToResource to assign an IfcActor to fulfill the role as the subcontractor. The attribute JobDescription has been deleted; use LongDescription to describe the job.
An IfcSubContractResource can be used in cost estimating and work planning with or without specifying the subcontractor and contract agreement.
The purpose of an IfcSubContractResource is to indicate work of a particular type that is that is to be engaged through the use of a sub-contract. It's aim is to identify the description of the sub-contract work required. It can be used to identify the generic type of sub-contract resource that is required for a purpose without having to be specific about the actor (person or organization) providing the resource occurrence. It may be particularly useful when creating an overall plan for a process or processes. For instance, within maintenance or work planning there may be a known task that needs to be done which is planned to require an 'insulation specialist'.
A subcontract resource may be described at various stages and levels of detail through its assignments:
- Subcontract resource designated for particular tasks
- Actors identified to request bids
- Cost schedules (bids) received from actors
- Project order (work order, change order, etc.) executed
Use definitions for composition, assignment, constraints, time series, and baselines are described at the base type IfcConstructionResource.
Type use definition
IfcSubContractResource defines the occurrence of any subcontract resource; common information about subcontract resource types is handled by IfcSubContractResourceType. The IfcSubContractResourceType (if present) may establish the common type name, common properties, and common productivities for various task types using IfcRelAssignsToProcess. The IfcSubContractResourceType is attached using the IfcRelDefinesByType.RelatingType objectified relationship and is accessible by the inverse IsTypedBy attribute.
Assignment use definition
In addition to assignments specified at the base class IfcConstructionResource, a subcontract resource may have assignments of its own using IfcRelAssignsToResource where RelatingResource refers to the IfcSubContractResource and RelatedObjects contains one or more IfcActor, IfcCostSchedule, and/or IfcWorkOrder objects as shown in Figure 195. An IfcActor indicates a specific organization to be considered to fulfill the resource or invited to bid on the resource. An IfcCostSchedule indicates a bid or price quote made on behalf of an organization. An IfcProjectOrder indicates a specific work order committed to fulfill the resource.
![]() |
Figure 195 — Subcontract assignment use |
"
2730;IfcConstructionProductResource;"
IfcConstructionProductResource defines the role of a product that is consumed (wholly or partially), or occupied in the performance of construction.
HISTORY: New Entity in IFC Release 2.0. Renamed from IfcProductResource in IFC 2x. Base type and documentation extended in IFC2x4.
Occurrences of IfcConstructionProductResource are usage of products to assist the process of construction. More specifically, they are usage of products that result from some construction processes and that are then used as resources to facilitate further construction. For instance, formworks can be instantiated as products resulting from the process ‘constructing formwork’. However, they are used as resources in the process ‘pouring concrete’ in a later stage of the project. IfcConstructionProductResource occurrences are explicitly instances of IfcProduct and may be drawn from various of the subtypes, for instance IfcElementComponent, IfcElementAssembly, IfcProxy (for particular cases where more precise usage details are not available). The product that is used as a construction resource is referenced using the IfcRelAssignsToResource.RelatedObjects relationship.
Use definitions for composition, assignment, constraints, time series, and baselines are described at the base type IfcConstructionResource.
Type use definition
IfcConstructionProductResource defines the occurrence of any product resource; common information about product resource types is handled by IfcConstructionProductResourceType. The IfcConstructionProductResourceType (if present) may establish the common type name, common properties, and common productivities for various task types using IfcRelAssignsToProcess. The IfcConstructionProductResourceType is attached using the IfcRelDefinesByType.RelatingType objectified relationship and is accessible by the inverse IsTypedBy attribute.
Assignment use definition
In addition to assignments specified at the base class IfcConstructionResource, a construction product resource may have assignments of its own using IfcRelAssignsToResource where RelatingResource refers to the IfcConstructionProductResource and RelatedObjects contains one or more IfcProduct subtypes as shown in Figure 185. Such relationship indicates the products used as input for the resource. Such products are not contained within a building structure but are referenced within a construction spatial zone, specifically IfcSpatialZone with PredefinedType=CONSTRUCTION, which is aggregated within the IfcProject. There may be multiple chains of production such that the assigned products may have their own task and resource assignments.
![]() |
Figure 185 — Construction product resource assignment |
"
2738;IfcConstructionMaterialResource;"
IfcConstructionMaterialResource identifies a material resource type in a construction project.
HISTORY: New Entity in IFC Release 2.0. Base type and documentation extended in IFC2x4.
IFC2x4 NOTE: The attribute Suppliers has been deleted; use IfcRelAssignsToResource to assign an IfcActor to fulfill the role as a supplier. The attribute UsageRatio has been deleted; use BaseQuantityConsumed and BaseQuantityProduced to indicate material usage.
Occurrences of IfcConstructionMaterialResource are consumed (wholly or partially), or occupied during a construction work task (IfcTask).
Similar to IfcConstructionProductResource, sometimes things such as 5000kg of gravel are already instantiated as an IfcProduct because it is a result of a work task (for example, ‘transporting gravel’). In this case, the instance of IfcConstructionMaterialResource can be associated with the product instance ‘5000kg of gravel’ to provide more information for resource uses. Nevertheless, IfcConstructionMaterialResource should only be used to represent resource usage (for example ‘gravel’), but not product substances (for example, ‘5000kg of gravel’).
Note: This class is not the same as IfcMaterial; the former can typically represent the type of bulk materials such as sand, gravels, nails and so on (note these can be instantiated from IfcProduct as well depending their uses in the system) used in a construction process. The latter is about physical materials used in a physical building element typically with detailed positioning (e.g. offset) and layering information.
Quantities for an IfcConstructionMaterialResource are defined through IfcRelDefinesByProperty and use IfcElementQuantity.
Use definitions for composition, assignment, constraints, time series, and baselines are described at the base type IfcConstructionResource.
Type use definition
IfcConstructionMaterialResource defines the occurrence of any material resource; common information about material resource types is handled by IfcConstructionMaterialResourceType. The IfcConstructionMaterialResourceType (if present) may establish the common type name, common properties, and common productivities for various task types using IfcRelAssignsToProcess. The IfcConstructionMaterialResourceType is attached using the IfcRelDefinesByType.RelatingType objectified relationship and is accessible by the inverse IsTypedBy attribute.
Quantity use definition
The quantities relating to the IfcConstructionMaterialResource are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship. It is accessible by the inverse IsDefinedBy relationship. The following base quantities are defined and should be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'. Other quantities can be defined being subjected to local standard of measurement with another string value assigned to Name and a value provided for MethodOfMeasurement.
Assignment use definition
In addition to assignments specified at the base class IfcConstructionResource, a construction material resource may have assignments of its own using IfcRelAssignsToResource where RelatingResource refers to the IfcConstructionMaterialResource and RelatedObjects contains one or more IfcProduct subtypes as shown in Figure 184. Such relationship indicates the physical material used as input for the resource. Such products are not contained within a building structure but are referenced within a construction spatial zone, specifically IfcSpatialZone with PredefinedType=CONSTRUCTION, which is aggregated within the IfcProject. The IfcGeographicElement object is used to represent the physical material occurrence, which may optionally have placement and representation indicating intended storage on the construction site. There may be multiple chains of production such that the assigned product material(s) may have their own task and resource assignments for transporting or extracting such material.
![]() |
Figure 184 — Construction material resource assignment |
"
2762;IfcConstructionResourceType;"
IfcConstructionResourceType is an abstract generalization of the different resource types used in construction projects, mainly labor, material, equipment and product resource types, plus subcontracted resource types and aggregations such as a crew resource type.
A resource type represents a model of ""use of something"" and does not necessarily correspond to a specific type of object such as a person or vehicle, but represents possible usages of such objects such as general labor or an equipment fleet. A resource type can either represent usage in general (consumption attributes defined but no task type assignment) or a task-specific resource type (production attributes defined and having an IfcTask assignment).
A construction resource type captures common productivities and cost rates for applying resources to particular task types.
HISTORY: New entity in IFC2x4.
Composition use definition
Resource types may be decomposed into nested resource types indicating productivities when applying the resource to specific task types using the IfcRelNests relationship where IfcRelNests.RelatingObject refers to the general resource type and IfcRelNests.RelatedObjects refers to one or more task-specific productivities. For example, an IfcLaborResourceType may be defined for ""Carpenter"" which may have a nested IfcLaborResourceType for ""Carpenter - Wall Framing"" and another nested IfcLaborResourceType for ""Carpenter - Drywall"", each of which may have productivities based according to specific task types (IfcTaskType).
Assignment use definition
Resource types may be assigned to process types (IfcTypeProcess subtypes) using the IfcRelAssignsToProcess relationship as shown in Figure 193. Such relationship indicates that the resource type applies to the process type for the use indicated (e.g. IfcTaskType.PredefinedType). Such relationship enables a scenario of placing an IfcProduct of a particular IfcTypeProduct, querying for a set of IfcTypeProcess process types for constructing such product (e.g. IfcTaskTypeEnum.CONSTRUCTION), querying each IfcTypeProcess for a set of IfcTypeResource resource types for carrying out the process, and finally choosing an IfcTypeProcess and IfcTypeResource combination resulting in the shortest time for instantiated IfcTask occurrence(s) and/or lowest-cost for instantiated IfcConstructionResource occurrence(s).
![]() |
Figure 193 — Construction resource type assignment |
"
2774;IfcCrewResourceType;"
The resource type IfcCrewResourceType defines commonly shared information for occurrences of crew resources. The set of shared information may include:
- common productivities
- common cost rates
- common properties within shared property sets
It is used to define a crew resource specification the specific resource information that is common to all occurrences of that resource). Resource types may be exchanged without being already assigned to occurrences.
Occurrences of the IfcCrewResourceType are represented by instances of IfcCrewResource.
HISTORY New entity in IFC2x4.
"
2777;IfcLaborResourceType;"
The resource type IfcLaborResourceType defines commonly shared information for occurrences of labor resources. The set of shared information may include:
- common productivities
- common cost rates
- common properties within shared property sets
It is used to define a labor resource specification (i.e. the specific resource information that is common to all occurrences of that resource). Resource types may be exchanged without being already assigned to occurrences.
Occurrences of the IfcLaborResourceType are represented by instances of IfcLaborResource.
HISTORY New entity in IFC2x4.
"
2780;IfcSubContractResourceType;"
The resource type IfcSubContractResourceType defines commonly shared information for occurrences of subcontract resources. The set of shared information may include:
- common productivities
- common cost rates
- common properties within shared property sets
It is used to define a subcontract resource specification (the specific resource information that is common to all
occurrences of that resource). Resource types may be exchanged without being already assigned to occurrences.
Occurrences of the IfcSubContractResourceType are represented by instances of IfcSubContractResource.
HISTORY New entity in IFC2x4.
"
2783;IfcConstructionMaterialResourceType;"
The resource type IfcConstructionMaterialType defines commonly shared information for occurrences of construction material resources. The set of shared information may include:
- common productivities
- common cost rates
- common properties within shared property sets
It is used to define a construction material resource specification (i.e. the specific resource information that is common to all occurrences of that resource). Resource types may be exchanged without being already assigned to occurrences.
Occurrences of the IfcConstructionMaterialResourceType are represented by instances of IfcConstructionMaterialResource.
HISTORY New entity in IFC2x4.
Assignment Use Definition
In addition to assignments specified at the base class IfcConstructionResourceType, a construction material resource type may have assignments of its own using IfcRelAssignsToResource where RelatingResource refers to the IfcConstructionMaterialResourceType and RelatedObjects contains one or more IfcTypeProduct subtypes. Such relationship indicates material specifications to be used as input, which is instantiated as an occurrence assigned for each resource occurrence. The IfcGeographicElementType product type may be used to hold the material representation (via IfcRelAssociatesMaterial. There may be multiple chains of production where such product type may have its own task and resource types assigned indicating how to transport or extract such material.
"
2786;IfcConstructionEquipmentResourceType;"
The resource type IfcConstructionEquipmentType defines commonly shared information for occurrences of construction equipment resources. The set of shared information may include:
- common productivities
- common cost rates
- common properties within shared property sets
It is used to define a construction equipment resource specification (the specific resource information that is common to all occurrences of that resource). Resource types may be exchanged without being already assigned to occurrences.
Occurrences of the IfcConstructionEquipmentResourceType are represented by instances of IfcConstructionEquipmentResource.
HISTORY New entity in IFC2x4.
Assignment use definition
In addition to assignments specified at the base class IfcConstructionResourceType, a construction equipment resource type may have assignments of its own using IfcRelAssignsToResource where RelatingResource refers to the IfcConstructionEquipmentResourceType and RelatedObjects contains one or more IfcTypeProduct subtypes. Such relationship indicates the type of equipment to be used as input, which is instantiated as an occurrence assigned for each resource occurrence. There may be multiple chains of production where such product type may have its own task and resource types assigned indicating how to assemble such equipment.
"
2789;IfcConstructionProductResourceType;"
The resource type IfcConstructionProductType defines commonly shared information for occurrences of construction product resources. The set of shared information may include:
- common productivities
- common cost rates
- common properties within shared property sets
It is used to define a construction product resource specification (i.e. the specific resource information that is common to all occurrences of that resource). Resource types may be exchanged without being already assigned to occurrences.
Occurrences of the IfcConstructionProductResourceType are represented by instances of IfcConstructionProductResource.
HISTORY New entity in IFC2x4.
Assignment use definition
In addition to assignments specified at the base class IfcConstructionResourceType, a construction product resource type may have assignments of its own using IfcRelAssignsToResource where RelatingResource refers to the IfcConstructionProductResourceType and RelatedObjects contains one or more IfcTypeProduct subtypes. Such relationship indicates the type of product to be used as input, which is instantiated as an occurrence assigned for each resource occurrence. There may be multiple chains of production where such product type may have its own task and resource types assigned.
"
2793;IfcMotorConnectionType;"
The energy conversion device type IfcMotorConnectionType defines commonly shared information for occurrences of motor connections. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a motor connection specification (i.e. the specific product information, that is common to all occurrences of that product type). Motor Connection types may be exchanged without being already assigned to occurrences.
Occurrences of IfcMotorConnectionType are represented by instances of IfcMotorConnection.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcEnergyConversionDeviceType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcMotorConnectionType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Casing': Material from which the casing is constructed.
Port Use Definition
The distribution ports relating to the IfcMotorConnectionType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcMotorConnection for standard port definitions.
"
2796;IfcOutletType;"
The flow terminal type IfcOutletType defines commonly shared information for occurrences of outlets. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a outlet specification (i.e. the specific product information, that is common to all occurrences of that product type). Outlet types may be exchanged without being already assigned to occurrences.
Occurrences of IfcOutletType are represented by instances of IfcOutlet.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowTerminalType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcOutletType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Casing': Material from which the casing is constructed.
- 'Conductor': Material from which the conductors are constructed.
- 'Surface': Material from which the outlet plate is constructed.
Port Use Definition
The distribution ports relating to the IfcOutletType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcOutlet for standard port definitions.
"
2807;IfcElectricApplianceType;"
The flow terminal type IfcElectricApplianceType defines commonly shared information for occurrences of electric appliances. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a electric appliance specification (i.e. the specific product information, that is common to all occurrences of that product type). Electric Appliance types may be exchanged without being already assigned to occurrences.
Occurrences of IfcElectricApplianceType are represented by instances of IfcElectricAppliance.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowTerminalType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity according to the PredefinedType attribute:
Material Use Definition
The material of the IfcElectricApplianceType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Casing': Material from which the casing is constructed.
Port Use Definition
The distribution ports relating to the IfcElectricApplianceType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcElectricAppliance for standard port definitions.
"
2829;IfcLightFixtureType;"
The flow terminal type IfcLightFixtureType defines commonly shared information for occurrences of light fixtures. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a light fixture specification (i.e. the specific product information, that is common to all occurrences of that product type). Light Fixture types may be exchanged without being already assigned to occurrences.
Occurrences of IfcLightFixtureType are represented by instances of IfcLightFixture.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowTerminalType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
The following property set definitions are applicable to this entity according to the PredefinedType attribute:
Material Use Definition
The material of the IfcLightFixtureType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Casing': Material from which the casing is constructed.
Port Use Definition
The distribution ports relating to the IfcLightFixtureType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcLightFixture for standard port definitions.
"
2838;IfcLampType;"
The flow terminal type IfcLampType defines commonly shared information for occurrences of lamps. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a lamp specification (i.e. the specific product information, that is common to all occurrences of that product type). Lamp types may be exchanged without being already assigned to occurrences.
Occurrences of IfcLampType are represented by instances of IfcLamp.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowTerminalType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcLampType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Bulb': Material from which the bulb is constructed (e.g. glass).
- 'Conductor': Material from which the conductor is constructed.
- 'Filament': Material from which the filament is constructed.
Port Use Definition
The distribution ports relating to the IfcLampType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcLamp for standard port definitions.
"
2853;IfcAudioVisualApplianceType;"
The flow terminal type IfcAudioVisualApplianceType defines commonly shared information for occurrences of audio-visual appliances. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a audio-visual appliance specification (i.e. the specific product information, that is common to all occurrences of that product type). Audio-Visual Appliance types may be exchanged without being already assigned to occurrences.
Occurrences of IfcAudioVisualApplianceType are represented by instances of IfcAudioVisualAppliance.
HISTORY: New entity in IFC2x4
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowTerminalType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
The following property set definitions are applicable to this entity according to the PredefinedType attribute:
Material Use Definition
The material of the IfcAudioVisualApplianceType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Casing': Material from which the casing is constructed.
Composition Use Definition
The IfcAudioVisualApplianceType may be aggregated into components using IfcRelAggregates where RelatingObject refers to the enclosing IfcAudioVisualApplianceType and RelatedObjects contains one or more components. Components are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Aggregation use is defined for the following predefined types:
Port Use Definition
The distribution ports relating to the IfcAudioVisualApplianceType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcAudioVisualAppliance for standard port definitions.
"
2870;IfcCommunicationsApplianceType;"
The flow terminal type IfcCommunicationsApplianceType defines commonly shared information for occurrences of communications appliances. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a communications appliance specification (i.e. the specific product information, that is common to all occurrences of that product type). Communications Appliance types may be exchanged without being already assigned to occurrences.
Occurrences of IfcCommunicationsApplianceType are represented by instances of IfcCommunicationsAppliance.
HISTORY: New entity in IFC2x4
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowTerminalType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcCommunicationsApplianceType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Casing': Material from which the casing is constructed.
Composition Use Definition
The IfcCommunicationsApplianceType may be aggregated into components using IfcRelAggregates where RelatingObject refers to the enclosing IfcCommunicationsApplianceType and RelatedObjects contains one or more components. Components are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Aggregation use is defined for the following predefined types:
- COMPUTER: May contain IfcAudioVisualAppliance components. Computers may be aggregated into audio-visual components such as displays, cameras, speakers, or microphones.
Port Use Definition
The distribution ports relating to the IfcCommunicationsApplianceType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcCommunicationsAppliance for standard port definitions.
"
2888;IfcSwitchingDeviceType;"
The flow controller type IfcSwitchingDeviceType defines commonly shared information for occurrences of switching devices. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a switching device specification (i.e. the specific product information, that is common to all occurrences of that product type). Switching Device types may be exchanged without being already assigned to occurrences.
Occurrences of IfcSwitchingDeviceType are represented by instances of IfcSwitchingDevice.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowControllerType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
The following property set definitions are applicable to this entity according to the PredefinedType attribute:
Material Use Definition
The material of the IfcSwitchingDeviceType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Casing': Material from which the casing is constructed.
- 'Conductor': Material from which the conductors are constructed.
- 'Surface': Material from which the switch surface is constructed.
Port Use Definition
The distribution ports relating to the IfcSwitchingDeviceType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcSwitchingDevice for standard port definitions.
"
2903;IfcElectricTimeControlType;"
The flow controller type IfcElectricTimeControlType defines commonly shared information for occurrences of electric time controls. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a electric time control specification (i.e. the specific product information, that is common to all occurrences of that product type). Electric Time Control types may be exchanged without being already assigned to occurrences.
Occurrences of IfcElectricTimeControlType are represented by instances of IfcElectricTimeControl.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowControllerType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcElectricTimeControlType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Casing': Material from which the casing is constructed.
Port Use Definition
The distribution ports relating to the IfcElectricTimeControlType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcElectricTimeControl for standard port definitions.
"
2912;IfcProtectiveDeviceType;"
The flow controller type IfcProtectiveDeviceType defines commonly shared information for occurrences of protective devices. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a protective device specification (i.e. the specific product information, that is common to all occurrences of that product type). Protective Device types may be exchanged without being already assigned to occurrences.
Occurrences of IfcProtectiveDeviceType are represented by instances of IfcProtectiveDevice.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowControllerType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
The following property set definitions are applicable to this entity according to the PredefinedType attribute:
Material Use Definition
The material of the IfcProtectiveDeviceType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Casing': Material from which the casing is constructed.
Port Use Definition
The distribution ports relating to the IfcProtectiveDeviceType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcProtectiveDevice for standard port definitions.
"
2925;IfcElectricDistributionBoardType;"
The flow controller type IfcElectricDistributionBoardType defines commonly shared information for occurrences of distribution boards. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a distribution board specification (i.e. the specific product information, that is common to all occurrences of that product type). Distribution Board types may be exchanged without being already assigned to occurrences.
Occurrences of IfcElectricDistributionBoardType are represented by instances of IfcElectricDistributionBoard.
HISTORY: New entity in IFC2x4
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowControllerType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcElectricDistributionBoardType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Casing': Material from which the casing is constructed.
Port Use Definition
The distribution ports relating to the IfcElectricDistributionBoardType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcElectricDistributionBoard for standard port definitions.
"
2935;IfcCableCarrierFittingType;"
The flow fitting type IfcCableCarrierFittingType defines commonly shared information for occurrences of cable carrier fittings. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a cable carrier fitting specification (i.e. the specific product information, that is common to all occurrences of that product type). Cable Carrier Fitting types may be exchanged without being already assigned to occurrences.
Occurrences of IfcCableCarrierFittingType are represented by instances of IfcCableCarrierFitting.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowFittingType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcCableCarrierFittingType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Body': The primary material from which the object is constructed.
Port Use Definition
The distribution ports relating to the IfcCableCarrierFittingType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcCableCarrierFitting for standard port definitions.
"
2945;IfcJunctionBoxType;"
The flow fitting type IfcJunctionBoxType defines commonly shared information for occurrences of junction boxs. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a junction box specification (i.e. the specific product information, that is common to all occurrences of that product type). Junction Box types may be exchanged without being already assigned to occurrences.
Occurrences of IfcJunctionBoxType are represented by instances of IfcJunctionBox.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowFittingType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcJunctionBoxType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Casing': Material from which the casing is constructed.
Port Use Definition
The distribution ports relating to the IfcJunctionBoxType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcJunctionBox for standard port definitions.
"
2953;IfcCableFittingType;"
The flow fitting type IfcCableFittingType defines commonly shared information for occurrences of cable fittings. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a cable fitting specification (i.e. the specific product information, that is common to all occurrences of that product type). Cable Fitting types may be exchanged without being already assigned to occurrences.
Occurrences of IfcCableFittingType are represented by instances of IfcCableFitting.
HISTORY: New entity in IFC2x4
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowFittingType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcCableFittingType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Casing': Material from which the casing is constructed.
- 'Conductor': Material from which the conductors are constructed, such as Aluminium or Copper.
Port Use Definition
The distribution ports relating to the IfcCableFittingType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcCableFitting for standard port definitions.
"
2964;IfcElectricFlowStorageDeviceType;"
The flow storage device type IfcElectricFlowStorageDeviceType defines commonly shared information for occurrences of electric flow storage devices. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a electric flow storage device specification (i.e. the specific product information, that is common to all occurrences of that product type). Electric Flow Storage Device types may be exchanged without being already assigned to occurrences.
Occurrences of IfcElectricFlowStorageDeviceType are represented by instances of IfcElectricFlowStorageDevice.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowStorageDeviceType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcElectricFlowStorageDeviceType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Casing': Material from which the casing is constructed.
Port Use Definition
The distribution ports relating to the IfcElectricFlowStorageDeviceType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcElectricFlowStorageDevice for standard port definitions.
"
2975;IfcCableSegmentType;"
The flow segment type IfcCableSegmentType defines commonly shared information for occurrences of cable segments. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a cable segment specification (i.e. the specific product information, that is common to all occurrences of that product type). Cable Segment types may be exchanged without being already assigned to occurrences.
Occurrences of IfcCableSegmentType are represented by instances of IfcCableSegment.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowSegmentType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
The following property set definitions are applicable to this entity according to the PredefinedType attribute:
Material Use Definition
The material of the IfcCableSegmentType is defined by IfcMaterialProfileSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialProfileSet.MaterialProfiles[n].Name shall be used:
- 'Conductor': The material from which the conductor is constructed such as Aluminium or Copper.
- 'Insulation': The material from which the insulation is constructed such as PVC, PEX, EPR, etc.
- 'Screen': The material from which the screen that covers the sheath is constructed (mantel) such as Aluminium, Copper, Steel , Lead.
- 'Sheath': The outer sheathing of the cable which may be color-coded.
Composition Use Definition
The IfcCableSegmentType may be aggregated into components using IfcRelAggregates where RelatingObject refers to the enclosing IfcCableSegmentType and RelatedObjects contains one or more components. Components are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Aggregation use is defined for the following predefined types:
Port Use Definition
The distribution ports relating to the IfcCableSegmentType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcCableSegment for standard port definitions.
"
2985;IfcCableCarrierSegmentType;"
The flow segment type IfcCableCarrierSegmentType defines commonly shared information for occurrences of cable carrier segments. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a cable carrier segment specification (i.e. the specific product information, that is common to all occurrences of that product type). Cable Carrier Segment types may be exchanged without being already assigned to occurrences.
Occurrences of IfcCableCarrierSegmentType are represented by instances of IfcCableCarrierSegment.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowSegmentType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
The following property set definitions are applicable to this entity according to the PredefinedType attribute:
Material Use Definition
The material of the IfcCableCarrierSegmentType is defined by IfcMaterialProfileSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialProfileSet.MaterialProfiles[n].Name shall be used:
- 'Body': Material from which the object is constructed.
Port Use Definition
The distribution ports relating to the IfcCableCarrierSegmentType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcCableCarrierSegment for standard port definitions.
"
2995;IfcProtectiveDeviceTrippingUnitType;"
The distribution control element type IfcProtectiveDeviceTrippingUnitType defines commonly shared information for occurrences of protective device tripping units. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a protective device tripping unit specification (i.e. the specific product information, that is common to all occurrences of that product type). Protective Device Tripping Unit types may be exchanged without being already assigned to occurrences.
Occurrences of IfcProtectiveDeviceTrippingUnitType are represented by instances of IfcProtectiveDeviceTrippingUnit.
HISTORY: New entity in IFC2x4
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcDistributionControlElementType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
The following property set definitions are applicable to this entity according to the PredefinedType attribute:
Material Use Definition
The material of the IfcProtectiveDeviceTrippingUnitType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Casing': Material from which the casing is constructed.
Port Use Definition
The distribution ports relating to the IfcProtectiveDeviceTrippingUnitType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcProtectiveDeviceTrippingUnit for standard port definitions.
"
3005;IfcCableSegment;"A cable segment is a flow segment used to carry electrical power, data, or telecommunications signals.
A cable segment is used to typically join two sections of an electrical network or a network of components carrying the electrical service.
HISTORY New entity in IFC2x4
Type Use Definition
IfcCableSegment defines the occurrence of any cable segment; common information about cable segment types is handled by IfcCableSegmentType.
The IfcCableSegmentType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcCableSegmentType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcCableSegmentType has ports or aggregated elements, such objects are reflected at the IfcCableSegment occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcCableSegmentType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcCableSegmentType.HasPropertySets.
If both are given, then the properties directly defined at IfcCableSegment override the properties defined at IfcCableSegmentType.
Refer to the documentation at the supertype IfcFlowSegment and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcCableSegment is defined by IfcMaterialProfileSetUsage or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcCableSegmentType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialProfileSet.MaterialProfiles[n].Name shall be used:
- Conductor: Material from which the conductors are constructed, such as Aluminium or Copper.
- Insulation: The material from which the insulation is constructed such as PVC, PEX, or EPR.
- Screen: The material from which the screen that covers the sheath is constructed (mantel) such as Aluminium, Copper, Steel, or Lead.
- Sheath: The outer sheathing of the cable which may be color-coded.
Composition Use Definition
The IfcCableSegment may be aggregated into components using IfcRelAggregates where RelatingObject refers to the enclosing IfcCableSegment and RelatedObjects contains one or more components. Aggregation use is defined for the following predefined types:
- CABLESEGMENT
- May contain IfcCableSegment components having PredefinedType=CORESEGMENT. Cable segments may be aggregated into cable cores.
- CORESEGMENT
- May contain IfcCableSegment components having PredefinedType=CONDUCTORSEGMENT. Cable cores may be aggregated into cable conductors.
Connection Use Definition
The IfcCableSegment may be connected to other objects as follows using the indicated relationship:
Port Use Definition
The distribution ports relating to the IfcCableSegment are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the cable segment occurrence is defined by IfcCableSegmentType, then the port occurrences must reflect those defined at the IfcCableSegmentType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcCableSegment PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
"
3009;IfcCableCarrierSegment;"A cable carrier segment is a flow segment that is specifically used to carry and support cabling.
HISTORY New entity in IFC2x4
Type Use Definition
IfcCableCarrierSegment defines the occurrence of any cable carrier segment; common information about cable carrier segment types is handled by IfcCableCarrierSegmentType.
The IfcCableCarrierSegmentType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcCableCarrierSegmentType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcCableCarrierSegmentType has ports or aggregated elements, such objects are reflected at the IfcCableCarrierSegment occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcCableCarrierSegmentType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcCableCarrierSegmentType.HasPropertySets.
If both are given, then the properties directly defined at IfcCableCarrierSegment override the properties defined at IfcCableCarrierSegmentType.
Refer to the documentation at the supertype IfcFlowSegment and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcCableCarrierSegment is defined by IfcMaterialProfileSetUsage or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcCableCarrierSegmentType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialProfileSet.MaterialProfiles[n].Name shall be used:
- Body: The primary material from which the object is constructed.
Port Use Definition
The distribution ports relating to the IfcCableCarrierSegment are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the cable carrier segment occurrence is defined by IfcCableCarrierSegmentType, then the port occurrences must reflect those defined at the IfcCableCarrierSegmentType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcCableCarrierSegment PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
"
3013;IfcCableCarrierFitting;"A cable carrier fitting is a fitting that is placed at junction or transition in a cable carrier system.
HISTORY New entity in IFC2x4
Type Use Definition
IfcCableCarrierFitting defines the occurrence of any cable carrier fitting; common information about cable carrier fitting types is handled by IfcCableCarrierFittingType.
The IfcCableCarrierFittingType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcCableCarrierFittingType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcCableCarrierFittingType has ports or aggregated elements, such objects are reflected at the IfcCableCarrierFitting occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcCableCarrierFittingType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcCableCarrierFittingType.HasPropertySets.
If both are given, then the properties directly defined at IfcCableCarrierFitting override the properties defined at IfcCableCarrierFittingType.
Refer to the documentation at the supertype IfcFlowFitting and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcCableCarrierFitting is defined by IfcMaterialProfileSetUsage or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcCableCarrierFittingType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialProfileSet.MaterialProfiles[n].Name shall be used:
- Body: The primary material from which the object is constructed.
Port Use Definition
The distribution ports relating to the IfcCableCarrierFitting are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the cable carrier fitting occurrence is defined by IfcCableCarrierFittingType, then the port occurrences must reflect those defined at the IfcCableCarrierFittingType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcCableCarrierFitting PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
"
3017;IfcCableFitting;"A cable fitting is a fitting that is placed at a junction, transition or termination in a cable system.
HISTORY New entity in IFC2x4
Type Use Definition
IfcCableFitting defines the occurrence of any cable fitting; common information about cable fitting types is handled by IfcCableFittingType.
The IfcCableFittingType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcCableFittingType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcCableFittingType has ports or aggregated elements, such objects are reflected at the IfcCableFitting occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcCableFittingType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcCableFittingType.HasPropertySets.
If both are given, then the properties directly defined at IfcCableFitting override the properties defined at IfcCableFittingType.
Refer to the documentation at the supertype IfcFlowFitting and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcCableFitting is defined by IfcMaterialProfileSetUsage or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcCableFittingType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialProfileSet.MaterialProfiles[n].Name shall be used:
- Casing: Material from which the casing is constructed.
- Conductor: Material from which the conductors are constructed, such as Aluminium or Copper.
Connection Use Definition
The IfcCableFitting may be connected to other objects as follows using the indicated relationship:
Port Use Definition
The distribution ports relating to the IfcCableFitting are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the cable fitting occurrence is defined by IfcCableFittingType, then the port occurrences must reflect those defined at the IfcCableFittingType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcCableFitting PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
"
3021;IfcJunctionBox;"A junction box is an enclosure within which cables are connected.
Cables may be members of an electrical circuit (for electrical power systems) or be information carriers (in a telecommunications system). A junction box is typically intended to conceal a cable junction from sight, eliminate tampering or provide a safe place for electrical connection.
HISTORY New entity in IFC2x4
Type Use Definition
IfcJunctionBox defines the occurrence of any junction box; common information about junction box types is handled by IfcJunctionBoxType.
The IfcJunctionBoxType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcJunctionBoxType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcJunctionBoxType has ports or aggregated elements, such objects are reflected at the IfcJunctionBox occurrence using the IfcRelDefinesByObject relationship.
Figure 200 illustrates junction box type use.
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Figure 200 — Junction box type use |
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcJunctionBoxType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcJunctionBoxType.HasPropertySets.
If both are given, then the properties directly defined at IfcJunctionBox override the properties defined at IfcJunctionBoxType.
Refer to the documentation at the supertype IfcFlowFitting and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcJunctionBox is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcJunctionBoxType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Casing: Material from which the casing is constructed.
Connection Use Definition
The IfcJunctionBox may be connected to other objects as follows using the indicated relationship:
Port Use Definition
The distribution ports relating to the IfcJunctionBox are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the junction box occurrence is defined by IfcJunctionBoxType, then the port occurrences must reflect those defined at the IfcJunctionBoxType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcJunctionBox PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
- DATA
- Line#1 (DATA, SINK): A data line, typically a cable connecting from a network router communications device.
- Line#2 (DATA, SINK): A data line, typically a cable connecting from a network router communications device.
- Gang#1 (DATA, SOURCE): A slot to house a data outlet containing one or more jacks, ordered from left-to-right.
- Gang#2 (DATA, SOURCE): A slot to house a data outlet containing one or more jacks, ordered from left-to-right.
- POWER
- Line (ELECTRICAL, SINK): The electrical supply line, typically a cable connecting from another junction box or from a protective device within a distribution board.
- Load (ELECTRICAL, SOURCE): The next load in the circuit, typically a cable connecting to another junction box.
- Gang#1 (ELECTRICAL, SOURCE): A slot to house a switch or outlet, ordered from left-to-right.
- Gang#2 (ELECTRICAL, SOURCE): A slot to house a switch or outlet, ordered from left-to-right.
- Gang#3 (ELECTRICAL, SOURCE): A slot to house a switch or outlet, ordered from left-to-right.
- Gang#4 (ELECTRICAL, SOURCE): A slot to house a switch or outlet, ordered from left-to-right.
Figure 201 illustrates junction box port use.
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Figure 201 — Junction box port use |
"
3025;IfcElectricFlowStorageDevice;"An electric flow storage device is a device in which electrical energy is stored and from which energy may be progressively released.
HISTORY New entity in IFC2x4
Type Use Definition
IfcElectricFlowStorageDevice defines the occurrence of any electric flow storage device; common information about electric flow storage device types is handled by IfcElectricFlowStorageDeviceType.
The IfcElectricFlowStorageDeviceType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcElectricFlowStorageDeviceType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcElectricFlowStorageDeviceType has ports or aggregated elements, such objects are reflected at the IfcElectricFlowStorageDevice occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcElectricFlowStorageDeviceType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcElectricFlowStorageDeviceType.HasPropertySets.
If both are given, then the properties directly defined at IfcElectricFlowStorageDevice override the properties defined at IfcElectricFlowStorageDeviceType.
Refer to the documentation at the supertype IfcFlowStorageDevice and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcElectricFlowStorageDevice is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcElectricFlowStorageDeviceType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Casing: Material from which the casing is constructed.
Port Use Definition
The distribution ports relating to the IfcElectricFlowStorageDevice are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the electric flow storage device occurrence is defined by IfcElectricFlowStorageDeviceType, then the port occurrences must reflect those defined at the IfcElectricFlowStorageDeviceType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcElectricFlowStorageDevice PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
- Line (ELECTRICAL, SINK): Incoming power used to charge the flow storage device.
- Load (ELECTRICAL, SOURCE): Outgoing power backed by the flow storage device.
"
3029;IfcOutlet;"An outlet is a device installed at a point to receive one or more inserted plugs for electrical power or communications.
Power outlets are commonly connected within a junction box; data outlets may be directly connected to a wall. For power outlets sharing the same circuit within a junction box, the ports should indicate the logical wiring relationship to the enclosing junction box, even though they may be physically connected to a cable going to another outlet, switch, or fixture.
HISTORY New entity in IFC2x4
Type Use Definition
IfcOutlet defines the occurrence of any outlet; common information about outlet types is handled by IfcOutletType.
The IfcOutletType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcOutletType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcOutletType has ports or aggregated elements, such objects are reflected at the IfcOutlet occurrence using the IfcRelDefinesByObject relationship.
Figure 206 illustrates outlet type use.
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Figure 206 — Outlet type use |
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcOutletType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcOutletType.HasPropertySets.
If both are given, then the properties directly defined at IfcOutlet override the properties defined at IfcOutletType.
Refer to the documentation at the supertype IfcFlowTerminal and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcOutlet is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcOutletType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Casing: Material from which the casing is constructed.
- Conductor: Material from which the conductors are constructed.
- Surface: Material from which the outer plate is constructed.
Port Use Definition
The distribution ports relating to the IfcOutlet are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the outlet occurrence is defined by IfcOutletType, then the port occurrences must reflect those defined at the IfcOutletType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcOutlet PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
- DATAOUTLET
- Line#1 (DATA, SINK): A data line, connecting to a cable commonly originating from a port on a router.
- Line#2 (DATA, SINK): A data line, connecting to a cable commonly originating from a port on a router.
- Jack#1 (DATA, SOURCE): Jacks in order of layout, going to the right and then down, which may accept a cable.
- Jack#2 (DATA, SOURCE): Jacks in order of layout, going to the right and then down, which may accept a cable.
- POWEROUTLET
- Line (ELECTRICAL, SINK): The source of power, which may refer to a port on a junction box.
- Jack#1 (ELECTRICAL, SOURCE): Upper jack, accepting a plug from an appliance or fixture.
- Jack#2 (ELECTRICAL, SOURCE): Lower jack, accepting a plug from an appliance or fixture.
- TELEPHONEOUTLET
- Line#1 (DATA, SINK): A telephone line, connecting to a cable originating from a telecommunications distribution board.
- Line#2 (DATA, SINK): A telephone line, connecting to a cable originating from a telecommunications distribution board.
- Jack#1 (DATA, SOURCE): Jacks in order of layout, going to the right and then down, which may accept a cable.
- Jack#2 (DATA, SOURCE): Jacks in order of layout, going to the right and then down, which may accept a cable.
Figure 207 illustrates outlet port use.
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Figure 207 — Outlet port use |
"
3033;IfcLightFixture;"A light fixture is a container that is designed for the purpose of housing one or more lamps and optionally devices that control, restrict or vary their emission.
HISTORY New entity in IFC2x4
Type Use Definition
IfcLightFixture defines the occurrence of any light fixture; common information about light fixture types is handled by IfcLightFixtureType.
The IfcLightFixtureType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcLightFixtureType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcLightFixtureType has ports or aggregated elements, such objects are reflected at the IfcLightFixture occurrence using the IfcRelDefinesByObject relationship.
Figure 204 illustrates light fixture type use.
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Figure 204 — Light fixture type use |
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcLightFixtureType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcLightFixtureType.HasPropertySets.
If both are given, then the properties directly defined at IfcLightFixture override the properties defined at IfcLightFixtureType.
Refer to the documentation at the supertype IfcFlowTerminal and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcLightFixture is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcLightFixtureType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Casing: Material from which the casing is constructed.
Connection Use Definition
The IfcLightFixture may be connected to other objects as follows using the indicated relationship:
Port Use Definition
The distribution ports relating to the IfcLightFixture are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the light fixture occurrence is defined by IfcLightFixtureType, then the port occurrences must reflect those defined at the IfcLightFixtureType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcLightFixture PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
- Line (ELECTRICAL, SINK): The power supply line, typically a cable connected to a switch.
- Socket#1 (LIGHTING, SOURCE): A lamp socket within the light fixture.
- Socket#2 (LIGHTING, SOURCE): A lamp socket within the light fixture.
- Socket#3 (LIGHTING, SOURCE): A lamp socket within the light fixture.
- Socket#4 (LIGHTING, SOURCE): A lamp socket within the light fixture.
- Socket#5 (LIGHTING, SOURCE): A lamp socket within the light fixture.
- Socket#6 (LIGHTING, SOURCE): A lamp socket within the light fixture.
- Socket#7 (LIGHTING, SOURCE): A lamp socket within the light fixture.
- Socket#8 (LIGHTING, SOURCE): A lamp socket within the light fixture.
Figure 205 illustrates light fixture port use.
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Figure 205 — Light fixture port use |
"
3037;IfcLamp;"A lamp is an artificial light source such as a light bulb or tube.
HISTORY New entity in IFC2x4
Type Use Definition
IfcLamp defines the occurrence of any lamp; common information about lamp types is handled by IfcLampType.
The IfcLampType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcLampType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcLampType has ports or aggregated elements, such objects are reflected at the IfcLamp occurrence using the IfcRelDefinesByObject relationship.
Figure 202 illustrates lamp type use.
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Figure 202 — Lamp type use |
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcLampType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcLampType.HasPropertySets.
If both are given, then the properties directly defined at IfcLamp override the properties defined at IfcLampType.
Refer to the documentation at the supertype IfcFlowTerminal and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcLamp is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcLampType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Bulb: Material from which the bulb is constructed such as glass.
- Conductor: Material from which the conductor is constructed.
- Filament: Material from which the filament is constructed.
Port Use Definition
The distribution ports relating to the IfcLamp are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the lamp occurrence is defined by IfcLampType, then the port occurrences must reflect those defined at the IfcLampType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcLamp PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
Figure 203 illustrates lamp port use.
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Figure 203 — Lamp port use |
"
3041;IfcElectricAppliance;"A communications appliance transmits and receives electronic or digital information as data or sound.
Communication appliances may be fixed in place or may be able to be moved from one space to another. Communication appliances require an electrical supply that may be supplied either by an electrical circuit or provided from a local battery source.
HISTORY New entity in IFC2x4
Type Use Definition
IfcElectricAppliance defines the occurrence of any electric appliance; common information about electric appliance types is handled by IfcElectricApplianceType.
The IfcElectricApplianceType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcElectricApplianceType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcElectricApplianceType has ports or aggregated elements, such objects are reflected at the IfcElectricAppliance occurrence using the IfcRelDefinesByObject relationship.
Figure 196 illustrates electric appliance type use.
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Figure 196 — Electric appliance type use |
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcElectricApplianceType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcElectricApplianceType.HasPropertySets.
If both are given, then the properties directly defined at IfcElectricAppliance override the properties defined at IfcElectricApplianceType.
Refer to the documentation at the supertype IfcFlowTerminal and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcElectricAppliance is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcElectricApplianceType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Casing: Material from which the casing is constructed.
Port Use Definition
The distribution ports relating to the IfcElectricAppliance are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the electric appliance occurrence is defined by IfcElectricApplianceType, then the port occurrences must reflect those defined at the IfcElectricApplianceType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcElectricAppliance PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
Figure 197 illustrates electric appliance port use.
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Figure 197 — Electric appliance port use |
"
3045;IfcAudioVisualAppliance;"An audio-visual appliance is a device that displays, captures, transmits, or receives audio or video.
Audio-visual appliances may be fixed in place or may be able to be moved from one space to another. They may require an electrical supply that may be supplied either by an electrical circuit or provided from a local battery source. Audio-visual appliances may be connected to data circuits including specialist circuits for audio visual purposes only.
HISTORY New entity in IFC2x4
Type Use Definition
IfcAudioVisualAppliance defines the occurrence of any audio visual appliance; common information about audio visual appliance types is handled by IfcAudioVisualApplianceType.
The IfcAudioVisualApplianceType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcAudioVisualApplianceType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcAudioVisualApplianceType has ports or aggregated elements, such objects are reflected at the IfcAudioVisualAppliance occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcAudioVisualApplianceType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcAudioVisualApplianceType.HasPropertySets.
If both are given, then the properties directly defined at IfcAudioVisualAppliance override the properties defined at IfcAudioVisualApplianceType.
Refer to the documentation at the supertype IfcFlowTerminal and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcAudioVisualAppliance is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcAudioVisualApplianceType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Casing: Material from which the casing is constructed.
Composition Use Definition
The IfcAudioVisualAppliance may be aggregated into components using IfcRelAggregates where RelatingObject refers to the enclosing IfcAudioVisualAppliance and RelatedObjects contains one or more components. Aggregation use is defined for the following predefined types:
- May contain IfcAudioVisualAppliance components.
Port Use Definition
The distribution ports relating to the IfcAudioVisualAppliance are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the audio visual appliance occurrence is defined by IfcAudioVisualApplianceType, then the port occurrences must reflect those defined at the IfcAudioVisualApplianceType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcAudioVisualAppliance PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
- AMPLIFIER
- CAMERA
- DISPLAY
- Power (ELECTRICAL, SINK): Receives electrical power.
- Control (CONTROL, SINK): Receives control signal.
- Input#1 (AUDIOVISUAL, SINK): Input audio/video source.
- Input#2 (AUDIOVISUAL, SINK): Input audio/video source.
- Input#3 (AUDIOVISUAL, SINK): Input audio/video source.
- Input#4 (AUDIOVISUAL, SINK): Input audio/video source.
- Input#5 (AUDIOVISUAL, SINK): Input audio/video source.
- Input#6 (AUDIOVISUAL, SINK): Input audio/video source.
- Input#7 (AUDIOVISUAL, SINK): Input audio/video source.
- Input#8 (AUDIOVISUAL, SINK): Input audio/video source.
- MICROPHONE
- PLAYER
- PROJECTOR
- RECEIVER
- Power (ELECTRICAL, SINK): Receives electrical power.
- Control (CONTROL, SINK): Receives control signal.
- Network (DATA, SOURCE): Network access.
- Input#1 (AUDIOVISUAL, SINK): Input audio/video source.
- Input#2 (AUDIOVISUAL, SINK): Input audio/video source.
- Input#3 (AUDIOVISUAL, SINK): Input audio/video source.
- Input#4 (AUDIOVISUAL, SINK): Input audio/video source.
- Input#5 (AUDIOVISUAL, SINK): Input audio/video source.
- Input#6 (AUDIOVISUAL, SINK): Input audio/video source.
- Input#7 (AUDIOVISUAL, SINK): Input audio/video source.
- Input#8 (AUDIOVISUAL, SINK): Input audio/video source.
- Output#1 (AUDIOVISUAL, SOURCE): Output audio/video zone.
- Output#2 (AUDIOVISUAL, SOURCE): Output audio/video zone.
- Speakers#1 (ELECTROACCOUSTIC, SOURCE): Audio speaker(s), which may be aggregated for separate speaker channels.
- Speakers#2 (ELECTROACCOUSTIC, SOURCE): Audio speaker(s), which may be aggregated for separate speaker channels.
- SPEAKER
- SWITCHER
- Power (ELECTRICAL, SINK): Receives electrical power.
- Control (CONTROL, SINK): Receives control signal.
- Network (DATA, SOURCE): Network access.
- Input#1 (AUDIOVISUAL, SINK): Input audio/video source.
- Input#2 (AUDIOVISUAL, SINK): Input audio/video source.
- Input#3 (AUDIOVISUAL, SINK): Input audio/video source.
- Input#4 (AUDIOVISUAL, SINK): Input audio/video source.
- Input#5 (AUDIOVISUAL, SINK): Input audio/video source.
- Input#6 (AUDIOVISUAL, SINK): Input audio/video source.
- Input#7 (AUDIOVISUAL, SINK): Input audio/video source.
- Input#8 (AUDIOVISUAL, SINK): Input audio/video source.
- Output#1 (AUDIOVISUAL, SOURCE): Output audio/video zone.
- Output#2 (AUDIOVISUAL, SOURCE): Output audio/video zone.
- Output#3 (AUDIOVISUAL, SOURCE): Output audio/video zone.
- Output#4 (AUDIOVISUAL, SOURCE): Output audio/video zone.
- Output#5 (AUDIOVISUAL, SOURCE): Output audio/video zone.
- Output#6 (AUDIOVISUAL, SOURCE): Output audio/video zone.
- Output#7 (AUDIOVISUAL, SOURCE): Output audio/video zone.
- Output#8 (AUDIOVISUAL, SOURCE): Output audio/video zone.
- TELEPHONE
- TUNER
- Power (ELECTRICAL, SINK): Receives electrical power.
- Control (CONTROL, SINK): Receives control signal.
- Input (TV, SINK): Receives modulated data feed such as satellite, cable, or over-the-air.
- Output (AUDIOVISUAL, SOURCE): Rendered media content.
"
3049;IfcCommunicationsAppliance;"A communications appliance transmits and receives electronic or digital information as data or sound.
Communication appliances may be fixed in place or may be able to be moved from one space to another. Communication appliances require an electrical supply that may be supplied either by an electrical circuit or provided from a local battery source.
HISTORY New entity in IFC2x4
Type Use Definition
IfcCommunicationsAppliance defines the occurrence of any communications appliance; common information about communications appliance types is handled by IfcCommunicationsApplianceType.
The IfcCommunicationsApplianceType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcCommunicationsApplianceType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcCommunicationsApplianceType has ports or aggregated elements, such objects are reflected at the IfcCommunicationsAppliance occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcCommunicationsApplianceType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcCommunicationsApplianceType.HasPropertySets.
If both are given, then the properties directly defined at IfcCommunicationsAppliance override the properties defined at IfcCommunicationsApplianceType.
Refer to the documentation at the supertype IfcFlowTerminal and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcCommunicationsAppliance is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcCommunicationsApplianceType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Casing: Material from which the casing is constructed.
Composition Use Definition
The IfcCommunicationsAppliance may be aggregated into components using IfcRelAggregates where RelatingObject refers to the enclosing IfcCommunicationsAppliance and RelatedObjects contains one or more components. Aggregation use is defined for the following predefined types:
- COMPUTER
- May contain IfcAudioVisualAppliance components. Computers may be aggregated into audio-visual components such as displays, cameras, speakers, or microphones.
Connection Use Definition
The IfcCommunicationsAppliance may be connected to other objects as follows using the indicated relationship:
Port Use Definition
The distribution ports relating to the IfcCommunicationsAppliance are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the communications appliance occurrence is defined by IfcCommunicationsApplianceType, then the port occurrences must reflect those defined at the IfcCommunicationsApplianceType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcCommunicationsAppliance PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
- ANTENNA
- Power (ELECTRICAL, SINK): Receives electrical power.
- Radio (SIGNAL, SINK): Electromagnetic waves.
- Signal (SIGNAL, SOURCE): The modulated analog signal in a circuit, such as a cable connected to a modem.
- COMPUTER
- Power (ELECTRICAL, SINK): Receives electrical power.
- Network (DATA, SINK): A network connection, may be wired or wireless (implicit antenna), such as a cable connected from a data outlet jack or from a router communications appliance. While communication is bidirectional, the router-end is considered to be the source.
- Device (CONTROL, SOURCE): A device connection such as USB or serial, which may connect to equipment such as a building automation controller.
- Display (AUDIOVISUAL, SOURCE): Audio/video output, such as a cable connected to a display, which may be aggregated into separate channels.
- FAX
- MODEM
- Power (ELECTRICAL, SINK): Receives electrical power.
- Signal (SIGNAL, SINK): Modulated analog signal, typically a cable connecting from a communications junction box or an antenna.
- Internet (DATA, SOURCE): Internet data network.
- Television (TV, SOURCE): Television modulated signal.
- Telephone (TELEPHONE, SOURCE): Telephone communications.
- PRINTER
- Power (ELECTRICAL, SINK): Receives electrical power.
- Network (DATA, SINK): A network connection, may be wired or wireless (implicit antenna), such as a cable connected from a data outlet jack or from a router communications appliance. While communication is bidirectional, the router-end is considered to be the source.
- REPEATER
- ROUTER
- Power (ELECTRICAL, SINK): Receives electrical power.
- Uplink (DATA, SINK): Uplink from another network, such as a cable connected to another router or the Internet.
- Link#1 (DATA, SOURCE): A network link to a routed device such as a cable connecting to a computer.
- Link#2 (DATA, SOURCE): A network link to a routed device such as a cable connecting to a computer.
- Link#3 (DATA, SOURCE): A network link to a routed device such as a cable connecting to a computer.
- Link#4 (DATA, SOURCE): A network link to a routed device such as a cable connecting to a computer.
- Link#5 (DATA, SOURCE): A network link to a routed device such as a cable connecting to a computer.
- Link#6 (DATA, SOURCE): A network link to a routed device such as a cable connecting to a computer.
- Link#7 (DATA, SOURCE): A network link to a routed device such as a cable connecting to a computer.
- Link#8 (DATA, SOURCE): A network link to a routed device such as a cable connecting to a computer.
"
3053;IfcSwitchingDevice;"A switch is used in a cable distribution system (electrical circuit) to control or modulate the flow of electricity.
Switches include those used for electrical power, communications, audio-visual, or other distribution system types as determined by the available ports.
HISTORY New entity in IFC2x4
Type Use Definition
IfcSwitchingDevice defines the occurrence of any switching device; common information about switching device types is handled by IfcSwitchingDeviceType.
The IfcSwitchingDeviceType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcSwitchingDeviceType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcSwitchingDeviceType has ports or aggregated elements, such objects are reflected at the IfcSwitchingDevice occurrence using the IfcRelDefinesByObject relationship.
Figure 208 illustrates switching device type use.
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Figure 208 — Switching device type use |
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcSwitchingDeviceType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcSwitchingDeviceType.HasPropertySets.
If both are given, then the properties directly defined at IfcSwitchingDevice override the properties defined at IfcSwitchingDeviceType.
Refer to the documentation at the supertype IfcFlowController and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcSwitchingDevice is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcSwitchingDeviceType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Casing: Material from which the casing is constructed.
- Conductor: Material from which the conductors are constructed.
- Surface: Material from which the switch surface is constructed.
Port Use Definition
The distribution ports relating to the IfcSwitchingDevice are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the switching device occurrence is defined by IfcSwitchingDeviceType, then the port occurrences must reflect those defined at the IfcSwitchingDeviceType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcSwitchingDevice PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
Figure 209 illustrates switching device port use.
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Figure 209 — Switching device port use |
"
3057;IfcProtectiveDevice;"A protective device breaks an electrical circuit when a stated electric current that passes through it is exceeded.
A protective device provides protection against electrical current only (not as a general protective device). It may be used to represent the complete set of elements including both the tripping unit and the breaking unit that provide the protection. This may be particularly useful at earlier stages of design where the approach to breaking the electrical supply may be determined but the method of tripping may not. Alternatively, this entity may be used to specifically represent the breaking unit alone (in which case the tripping unit will also be specifically identified). This entity is specific to dedicated protective devices and excludes electrical outlets that may have circuit protection.
HISTORY New entity in IFC2x4
Type Use Definition
IfcProtectiveDevice defines the occurrence of any protective device; common information about protective device types is handled by IfcProtectiveDeviceType.
The IfcProtectiveDeviceType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcProtectiveDeviceType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcProtectiveDeviceType has ports or aggregated elements, such objects are reflected at the IfcProtectiveDevice occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcProtectiveDeviceType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcProtectiveDeviceType.HasPropertySets.
If both are given, then the properties directly defined at IfcProtectiveDevice override the properties defined at IfcProtectiveDeviceType.
Refer to the documentation at the supertype IfcFlowController and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcProtectiveDevice is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcProtectiveDeviceType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Casing: Material from which the casing is constructed.
Port Use Definition
The distribution ports relating to the IfcProtectiveDevice are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the protective device occurrence is defined by IfcProtectiveDeviceType, then the port occurrences must reflect those defined at the IfcProtectiveDeviceType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcProtectiveDevice PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
- CIRCUITBREAKER
- Line (ELECTRICAL, SINK): The supply line, typically connected from a slot in a distribution board.
- Load (ELECTRICAL, SOURCE): The load protected by this device, typically a cable connected to a device or the first junction box of a circuit.
"
3061;IfcElectricDistributionBoard;"A distribution board is a flow controller in which instances of electrical devices are brought together at a single place for a particular purpose.
A distribution provides a housing for connected electrical distribution elements so that they can be viewed, operated or acted upon from a single place. Each connected item may have its own geometric representation and location.
HISTORY New entity in IFC2x4
Type Use Definition
IfcElectricDistributionBoard defines the occurrence of any electric distribution board; common information about electric distribution board types is handled by IfcElectricDistributionBoardType.
The IfcElectricDistributionBoardType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcElectricDistributionBoardType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcElectricDistributionBoardType has ports or aggregated elements, such objects are reflected at the IfcElectricDistributionBoard occurrence using the IfcRelDefinesByObject relationship.
Figure 198 illustrates electric distribution board type use.
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Figure 198 — Electric distribution board type use |
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcElectricDistributionBoardType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcElectricDistributionBoardType.HasPropertySets.
If both are given, then the properties directly defined at IfcElectricDistributionBoard override the properties defined at IfcElectricDistributionBoardType.
Refer to the documentation at the supertype IfcFlowController and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcElectricDistributionBoard is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcElectricDistributionBoardType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Casing: Material from which the casing is constructed.
Port Use Definition
The distribution ports relating to the IfcElectricDistributionBoard are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the electric distribution board occurrence is defined by IfcElectricDistributionBoardType, then the port occurrences must reflect those defined at the IfcElectricDistributionBoardType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcElectricDistributionBoard PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
- CONSUMERUNIT
- Line (ELECTRICAL, SINK): Incoming power, such as a cable connecting from the electrical utility or another distribution board.
- Ground (EARTHING, SOURCE): Grounding connection, such as a cable connecting to a cable fitting connected to a cold water pipe segment coming from the ground.
- Circuit#1 (ELECTRICAL, SOURCE): A downstream circuit, typically a circuit breaker protective device.
- Circuit#2 (ELECTRICAL, SOURCE): A downstream circuit, typically a circuit breaker protective device.
- Circuit#3 (ELECTRICAL, SOURCE): A downstream circuit, typically a circuit breaker protective device.
- Circuit#4 (ELECTRICAL, SOURCE): A downstream circuit, typically a circuit breaker protective device.
- Circuit#5 (ELECTRICAL, SOURCE): A downstream circuit, typically a circuit breaker protective device.
- Circuit#6 (ELECTRICAL, SOURCE): A downstream circuit, typically a circuit breaker protective device.
- Circuit#7 (ELECTRICAL, SOURCE): A downstream circuit, typically a circuit breaker protective device.
- Circuit#8 (ELECTRICAL, SOURCE): A downstream circuit, typically a circuit breaker protective device.
Figure 199 illustrates electric distribution board port use.
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Figure 199 — Electric distribution board port use |
"
3065;IfcElectricTimeControl;"An electric time control is a device that applies control to the provision or flow of electrical energy over time.
HISTORY New entity in IFC2x4
Type Use Definition
IfcElectricTimeControl defines the occurrence of any electric time control; common information about electric time control types is handled by IfcElectricTimeControlType.
The IfcElectricTimeControlType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcElectricTimeControlType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcElectricTimeControlType has ports or aggregated elements, such objects are reflected at the IfcElectricTimeControl occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcElectricTimeControlType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcElectricTimeControlType.HasPropertySets.
If both are given, then the properties directly defined at IfcElectricTimeControl override the properties defined at IfcElectricTimeControlType.
Refer to the documentation at the supertype IfcFlowController and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcElectricTimeControl is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcElectricTimeControlType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Casing: Material from which the casing is constructed.
Port Use Definition
The distribution ports relating to the IfcElectricTimeControl are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the electric time control occurrence is defined by IfcElectricTimeControlType, then the port occurrences must reflect those defined at the IfcElectricTimeControlType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcElectricTimeControl PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
"
3069;IfcTransformer;"A transformer is an inductive stationary device that transfers electrical energy from one circuit to another.
IfcTransformer is used to transform electric power; conversion of electric signals for other purposes is handled at other entities: IfcController converts arbitrary signals, IfcAudioVisualAppliance converts signals for audio or video streams, and IfcCommunicationsAppliance converts signals for data or other communications usage.
HISTORY New entity in IFC2x4
Type Use Definition
IfcTransformer defines the occurrence of any transformer; common information about transformer types is handled by IfcTransformerType.
The IfcTransformerType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcTransformerType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcTransformerType has ports or aggregated elements, such objects are reflected at the IfcTransformer occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcTransformerType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcTransformerType.HasPropertySets.
If both are given, then the properties directly defined at IfcTransformer override the properties defined at IfcTransformerType.
Refer to the documentation at the supertype IfcEnergyConversionDevice and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcTransformer is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcTransformerType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Casing: Material from which the casing is constructed.
Port Use Definition
The distribution ports relating to the IfcTransformer are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the transformer occurrence is defined by IfcTransformerType, then the port occurrences must reflect those defined at the IfcTransformerType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcTransformer PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
"
3081;IfcElectricGenerator;"An electric generator is an engine that is a machine for converting mechanical energy into electrical energy.
HISTORY New entity in IFC2x4
Type Use Definition
IfcElectricGenerator defines the occurrence of any electric generator; common information about electric generator types is handled by IfcElectricGeneratorType.
The IfcElectricGeneratorType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcElectricGeneratorType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcElectricGeneratorType has ports or aggregated elements, such objects are reflected at the IfcElectricGenerator occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcElectricGeneratorType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcElectricGeneratorType.HasPropertySets.
If both are given, then the properties directly defined at IfcElectricGenerator override the properties defined at IfcElectricGeneratorType.
Refer to the documentation at the supertype IfcEnergyConversionDevice and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcElectricGenerator is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcElectricGeneratorType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Casing: Material from which the casing is constructed.
Composition Use Definition
The IfcElectricGenerator may be aggregated into components using IfcRelAggregates where RelatingObject refers to the enclosing IfcElectricGenerator and RelatedObjects contains one or more components. Aggregation use is defined for the following predefined types:
- ENGINEGENERATOR
- May contain IfcEngine components. Engine-Generator sets may optionally include an engine to indicate specific detail.
Port Use Definition
The distribution ports relating to the IfcElectricGenerator are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the electric generator occurrence is defined by IfcElectricGeneratorType, then the port occurrences must reflect those defined at the IfcElectricGeneratorType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcElectricGenerator PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
"
3091;IfcElectricMotor;"An electric motor is an engine that is a machine for converting electrical energy into mechanical energy.
HISTORY New entity in IFC2x4
Type Use Definition
IfcElectricMotor defines the occurrence of any electric motor; common information about electric motor types is handled by IfcElectricMotorType.
The IfcElectricMotorType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcElectricMotorType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcElectricMotorType has ports or aggregated elements, such objects are reflected at the IfcElectricMotor occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcElectricMotorType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcElectricMotorType.HasPropertySets.
If both are given, then the properties directly defined at IfcElectricMotor override the properties defined at IfcElectricMotorType.
Refer to the documentation at the supertype IfcEnergyConversionDevice and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcElectricMotor is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcElectricMotorType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Casing: Material from which the casing is constructed.
Port Use Definition
The distribution ports relating to the IfcElectricMotor are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the electric motor occurrence is defined by IfcElectricMotorType, then the port occurrences must reflect those defined at the IfcElectricMotorType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcElectricMotor PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
"
3103;IfcMotorConnection;"A motor connection provides the means for connecting a motor as the driving device to the driven device.
HISTORY New entity in IFC2x4
Type Use Definition
IfcMotorConnection defines the occurrence of any motor connection; common information about motor connection types is handled by IfcMotorConnectionType.
The IfcMotorConnectionType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcMotorConnectionType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcMotorConnectionType has ports or aggregated elements, such objects are reflected at the IfcMotorConnection occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcMotorConnectionType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcMotorConnectionType.HasPropertySets.
If both are given, then the properties directly defined at IfcMotorConnection override the properties defined at IfcMotorConnectionType.
Refer to the documentation at the supertype IfcEnergyConversionDevice and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcMotorConnection is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcMotorConnectionType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Casing: Material from which the casing is constructed.
Port Use Definition
The distribution ports relating to the IfcMotorConnection are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the motor connection occurrence is defined by IfcMotorConnectionType, then the port occurrences must reflect those defined at the IfcMotorConnectionType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcMotorConnection PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
"
3113;IfcSolarDevice;"A solar device converts solar radiation into other energy such as electric current or thermal energy.
HISTORY New entity in IFC2x4
Type Use Definition
IfcSolarDevice defines the occurrence of any solar device; common information about solar device types is handled by IfcSolarDeviceType.
The IfcSolarDeviceType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcSolarDeviceType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcSolarDeviceType has ports or aggregated elements, such objects are reflected at the IfcSolarDevice occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcSolarDeviceType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcSolarDeviceType.HasPropertySets.
If both are given, then the properties directly defined at IfcSolarDevice override the properties defined at IfcSolarDeviceType.
Refer to the documentation at the supertype IfcEnergyConversionDevice and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcSolarDevice is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcSolarDeviceType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Casing: Material from which the casing is constructed.
Port Use Definition
The distribution ports relating to the IfcSolarDevice are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the solar device occurrence is defined by IfcSolarDeviceType, then the port occurrences must reflect those defined at the IfcSolarDeviceType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcSolarDevice PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
"
3122;IfcProtectiveDeviceTrippingUnit;"Entity Definition
HISTORY New entity in IFC2x4
Type Use Definition
IfcProtectiveDeviceTrippingUnit defines the occurrence of any protective device tripping unit; common information about protective device tripping unit types is handled by IfcProtectiveDeviceTrippingUnitType.
The IfcProtectiveDeviceTrippingUnitType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcProtectiveDeviceTrippingUnitType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcProtectiveDeviceTrippingUnitType has ports or aggregated elements, such objects are reflected at the IfcProtectiveDeviceTrippingUnit occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcProtectiveDeviceTrippingUnitType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcProtectiveDeviceTrippingUnitType.HasPropertySets.
If both are given, then the properties directly defined at IfcProtectiveDeviceTrippingUnit override the properties defined at IfcProtectiveDeviceTrippingUnitType.
Refer to the documentation at the supertype IfcDistributionControlElement and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
"
3126;IfcElectricGeneratorType;"
The energy conversion device type IfcElectricGeneratorType defines commonly shared information for occurrences of electric generators. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a electric generator specification (i.e. the specific product information, that is common to all occurrences of that product type). Electric Generator types may be exchanged without being already assigned to occurrences.
Occurrences of IfcElectricGeneratorType are represented by instances of IfcElectricGenerator.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcEnergyConversionDeviceType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcElectricGeneratorType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Casing': Material from which the casing is constructed.
Composition Use Definition
The IfcElectricGeneratorType may be aggregated into components using IfcRelAggregates where RelatingObject refers to the enclosing IfcElectricGeneratorType and RelatedObjects contains one or more components. Components are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Aggregation use is defined for the following predefined types:
- ENGINEGENERATOR: May contain IfcEngine components. Engine-Generator sets may optionally include an engine to indicate specific detail.
Port Use Definition
The distribution ports relating to the IfcElectricGeneratorType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcElectricGenerator for standard port definitions.
"
3129;IfcTransformerType;"
The energy conversion device type IfcTransformerType defines commonly shared information for occurrences of transformers. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a transformer specification (i.e. the specific product information, that is common to all occurrences of that product type). Transformer types may be exchanged without being already assigned to occurrences.
Occurrences of IfcTransformerType are represented by instances of IfcTransformer.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcEnergyConversionDeviceType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcTransformerType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Casing': Material from which the casing is constructed.
Port Use Definition
The distribution ports relating to the IfcTransformerType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcTransformer for standard port definitions.
"
3132;IfcElectricMotorType;"
The energy conversion device type IfcElectricMotorType defines commonly shared information for occurrences of electric motors. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a electric motor specification (i.e. the specific product information, that is common to all occurrences of that product type). Electric Motor types may be exchanged without being already assigned to occurrences.
Occurrences of IfcElectricMotorType are represented by instances of IfcElectricMotor.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcEnergyConversionDeviceType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcElectricMotorType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Casing': Material from which the casing is constructed.
Port Use Definition
The distribution ports relating to the IfcElectricMotorType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcElectricMotor for standard port definitions.
"
3135;IfcSolarDeviceType;"
The energy conversion device type IfcSolarDeviceType defines commonly shared information for occurrences of solar devices. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a solar device specification (i.e. the specific product information, that is common to all occurrences of that product type). Solar Device types may be exchanged without being already assigned to occurrences.
Occurrences of IfcSolarDeviceType are represented by instances of IfcSolarDevice.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcEnergyConversionDeviceType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcSolarDeviceType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Casing': Material from which the casing is constructed.
Port Use Definition
The distribution ports relating to the IfcSolarDeviceType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcSolarDevice for standard port definitions.
"
3139;IfcAirToAirHeatRecoveryType;"
The energy conversion device type IfcAirToAirHeatRecoveryType defines commonly shared information for occurrences of air-to-air heat recovery devices. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a air-to-air heat recovery device specification (i.e. the specific product information, that is common to all occurrences of that product type). Air-To-Air Heat Recovery Device types may be exchanged without being already assigned to occurrences.
Occurrences of IfcAirToAirHeatRecoveryType are represented by instances of IfcAirToAirHeatRecovery.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcEnergyConversionDeviceType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcAirToAirHeatRecoveryType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Media': The primary media material used for heat transfer.
Port Use Definition
The distribution ports relating to the IfcAirToAirHeatRecoveryType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcAirToAirHeatRecovery for standard port definitions.
"
3154;IfcBoilerType;"
The energy conversion device type IfcBoilerType defines commonly shared information for occurrences of boilers. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a boiler specification (i.e. the specific product information, that is common to all occurrences of that product type). Boiler types may be exchanged without being already assigned to occurrences.
Occurrences of IfcBoilerType are represented by instances of IfcBoiler.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcEnergyConversionDeviceType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
The following property set definitions are applicable to this entity according to the PredefinedType attribute:
Material Use Definition
The material of the IfcBoilerType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Body': The primary material from which the object is constructed.
Port Use Definition
The distribution ports relating to the IfcBoilerType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcBoiler for standard port definitions.
"
3162;IfcBurnerType;"
The energy conversion device type IfcBurnerType defines commonly shared information for occurrences of burners. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a burner specification (i.e. the specific product information, that is common to all occurrences of that product type). Burner types may be exchanged without being already assigned to occurrences.
Occurrences of IfcBurnerType are represented by instances of IfcBurner.
HISTORY: New entity in IFC2x4
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcEnergyConversionDeviceType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcBurnerType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Casing': Material from which the casing is constructed.
- 'Fuel': Material designed to be burned.
Port Use Definition
The distribution ports relating to the IfcBurnerType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcBurner for standard port definitions.
"
3168;IfcChillerType;"
The energy conversion device type IfcChillerType defines commonly shared information for occurrences of chillers. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a chiller specification (i.e. the specific product information, that is common to all occurrences of that product type). Chiller types may be exchanged without being already assigned to occurrences.
Occurrences of IfcChillerType are represented by instances of IfcChiller.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcEnergyConversionDeviceType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcChillerType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Casing': Material from which the casing is constructed.
- 'Refrigerant': Refrigerant material.
Composition Use Definition
The IfcChillerType may be aggregated into components using IfcRelAggregates where RelatingObject refers to the enclosing IfcChillerType and RelatedObjects contains one or more components. Components are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Aggregation use is defined for the following predefined types:
- (All Types): May contain IfcDistributionElement components. Chillers may aggregate distribution flow elements forming a refrigeration cycle (compressor, condenser, valve, evaporator), as well as control elements.
Port Use Definition
The distribution ports relating to the IfcChillerType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcChiller for standard port definitions.
"
3177;IfcCoilType;"
The energy conversion device type IfcCoilType defines commonly shared information for occurrences of coils. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a coil specification (i.e. the specific product information, that is common to all occurrences of that product type). Coil types may be exchanged without being already assigned to occurrences.
Occurrences of IfcCoilType are represented by instances of IfcCoil.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcEnergyConversionDeviceType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcCoilType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Body': The primary material from which the object is constructed.
Port Use Definition
The distribution ports relating to the IfcCoilType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcCoil for standard port definitions.
"
3190;IfcCondenserType;"
The energy conversion device type IfcCondenserType defines commonly shared information for occurrences of condensers. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a condenser specification (i.e. the specific product information, that is common to all occurrences of that product type). Condenser types may be exchanged without being already assigned to occurrences.
Occurrences of IfcCondenserType are represented by instances of IfcCondenser.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcEnergyConversionDeviceType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcCondenserType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Casing': Material from which the casing is constructed.
- 'Refrigerant': Refrigerant material.
Port Use Definition
The distribution ports relating to the IfcCondenserType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcCondenser for standard port definitions.
"
3203;IfcCooledBeamType;"
The energy conversion device type IfcCooledBeamType defines commonly shared information for occurrences of cooled beams. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a cooled beam specification (i.e. the specific product information, that is common to all occurrences of that product type). Cooled Beam types may be exchanged without being already assigned to occurrences.
Occurrences of IfcCooledBeamType are represented by instances of IfcCooledBeam.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcEnergyConversionDeviceType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
The following property set definitions are applicable to this entity according to the PredefinedType attribute:
Material Use Definition
The material of the IfcCooledBeamType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Body': The primary material from which the object is constructed.
Port Use Definition
The distribution ports relating to the IfcCooledBeamType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcCooledBeam for standard port definitions.
"
3211;IfcCoolingTowerType;"
The energy conversion device type IfcCoolingTowerType defines commonly shared information for occurrences of cooling towers. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a cooling tower specification (i.e. the specific product information, that is common to all occurrences of that product type). Cooling Tower types may be exchanged without being already assigned to occurrences.
Occurrences of IfcCoolingTowerType are represented by instances of IfcCoolingTower.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcEnergyConversionDeviceType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcCoolingTowerType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Casing': Material from which the casing is constructed.
- 'Fill': Fill material.
Composition Use Definition
The IfcCoolingTowerType may be aggregated into components using IfcRelAggregates where RelatingObject refers to the enclosing IfcCoolingTowerType and RelatedObjects contains one or more components. Components are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Aggregation use is defined for the following predefined types:
Port Use Definition
The distribution ports relating to the IfcCoolingTowerType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcCoolingTower for standard port definitions.
"
3220;IfcEvaporativeCoolerType;"
The energy conversion device type IfcEvaporativeCoolerType defines commonly shared information for occurrences of evaporative coolers. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a evaporative cooler specification (i.e. the specific product information, that is common to all occurrences of that product type). Evaporative Cooler types may be exchanged without being already assigned to occurrences.
Occurrences of IfcEvaporativeCoolerType are represented by instances of IfcEvaporativeCooler.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcEnergyConversionDeviceType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcEvaporativeCoolerType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Media': Heat exchanger media material.
Port Use Definition
The distribution ports relating to the IfcEvaporativeCoolerType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcEvaporativeCooler for standard port definitions.
"
3235;IfcEvaporatorType;"
The energy conversion device type IfcEvaporatorType defines commonly shared information for occurrences of evaporators. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a evaporator specification (i.e. the specific product information, that is common to all occurrences of that product type). Evaporator types may be exchanged without being already assigned to occurrences.
Occurrences of IfcEvaporatorType are represented by instances of IfcEvaporator.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcEnergyConversionDeviceType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcEvaporatorType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Refrigerant': Refrigerant material.
Port Use Definition
The distribution ports relating to the IfcEvaporatorType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcEvaporator for standard port definitions.
"
3247;IfcHeatExchangerType;"
The energy conversion device type IfcHeatExchangerType defines commonly shared information for occurrences of heat exchangers. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a heat exchanger specification (i.e. the specific product information, that is common to all occurrences of that product type). Heat Exchanger types may be exchanged without being already assigned to occurrences.
Occurrences of IfcHeatExchangerType are represented by instances of IfcHeatExchanger.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcEnergyConversionDeviceType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
The following property set definitions are applicable to this entity according to the PredefinedType attribute:
Material Use Definition
The material of the IfcHeatExchangerType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Shell': Material used to construct the shell of the heat exchanger.
Port Use Definition
The distribution ports relating to the IfcHeatExchangerType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcHeatExchanger for standard port definitions.
"
3255;IfcHumidifierType;"
The energy conversion device type IfcHumidifierType defines commonly shared information for occurrences of humidifiers. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a humidifier specification (i.e. the specific product information, that is common to all occurrences of that product type). Humidifier types may be exchanged without being already assigned to occurrences.
Occurrences of IfcHumidifierType are represented by instances of IfcHumidifier.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcEnergyConversionDeviceType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcHumidifierType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Casing': Material from which the casing is constructed.
Port Use Definition
The distribution ports relating to the IfcHumidifierType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcHumidifier for standard port definitions.
"
3274;IfcTubeBundleType;"
The energy conversion device type IfcTubeBundleType defines commonly shared information for occurrences of tube bundles. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a tube bundle specification (i.e. the specific product information, that is common to all occurrences of that product type). Tube Bundle types may be exchanged without being already assigned to occurrences.
Occurrences of IfcTubeBundleType are represented by instances of IfcTubeBundle.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcEnergyConversionDeviceType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
The following property set definitions are applicable to this entity according to the PredefinedType attribute:
Material Use Definition
The material of the IfcTubeBundleType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Body': Material used for construction of the tubes.
Port Use Definition
The distribution ports relating to the IfcTubeBundleType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcTubeBundle for standard port definitions.
"
3281;IfcUnitaryEquipmentType;"
The energy conversion device type IfcUnitaryEquipmentType defines commonly shared information for occurrences of unitary equipments. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a unitary equipment specification (i.e. the specific product information, that is common to all occurrences of that product type). Unitary Equipment types may be exchanged without being already assigned to occurrences.
Occurrences of IfcUnitaryEquipmentType are represented by instances of IfcUnitaryEquipment.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcEnergyConversionDeviceType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcUnitaryEquipmentType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute.
Composition Use Definition
The IfcUnitaryEquipmentType may be aggregated into components using IfcRelAggregates where RelatingObject refers to the enclosing IfcUnitaryEquipmentType and RelatedObjects contains one or more components. Components are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Aggregation use is defined for the following predefined types:
- (All Types): May contain IfcDistributionElement components. Unitary equipment (air handlers in particular) may elaborate contained elements such as dampers, fans, coils, sensors, actuators, and controllers. Such breakdown provides access to component information and tracking of performance history for embedded elements.
Port Use Definition
The distribution ports relating to the IfcUnitaryEquipmentType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcUnitaryEquipment for standard port definitions.
"
3292;IfcEngineType;"
The energy conversion device type IfcEngineType defines commonly shared information for occurrences of engines. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a engine specification (i.e. the specific product information, that is common to all occurrences of that product type). Engine types may be exchanged without being already assigned to occurrences.
Occurrences of IfcEngineType are represented by instances of IfcEngine.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcEnergyConversionDeviceType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcEngineType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Casing': Material from which the casing is constructed.
Port Use Definition
The distribution ports relating to the IfcEngineType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcEngine for standard port definitions.
"
3300;IfcFanType;"
The flow moving device type IfcFanType defines commonly shared information for occurrences of fans. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a fan specification (i.e. the specific product information, that is common to all occurrences of that product type). Fan types may be exchanged without being already assigned to occurrences.
Occurrences of IfcFanType are represented by instances of IfcFan.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowMovingDeviceType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcFanType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Housing': The material used to construct the fan housing.
- 'Wheel': The material used to construct the fan wheel.
Port Use Definition
The distribution ports relating to the IfcFanType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcFan for standard port definitions.
"
3313;IfcCompressorType;"
The flow moving device type IfcCompressorType defines commonly shared information for occurrences of compressors. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a compressor specification (i.e. the specific product information, that is common to all occurrences of that product type). Compressor types may be exchanged without being already assigned to occurrences.
Occurrences of IfcCompressorType are represented by instances of IfcCompressor.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowMovingDeviceType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcCompressorType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Body': The primary material from which the object is constructed.
- 'Refrigerant': Refrigerant material.
Port Use Definition
The distribution ports relating to the IfcCompressorType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcCompressor for standard port definitions.
"
3334;IfcPumpType;"
The flow moving device type IfcPumpType defines commonly shared information for occurrences of pumps. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a pump specification (i.e. the specific product information, that is common to all occurrences of that product type). Pump types may be exchanged without being already assigned to occurrences.
Occurrences of IfcPumpType are represented by instances of IfcPump.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowMovingDeviceType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcPumpType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Casing': Material from which the casing is constructed.
- 'Impeller': Material from which the impeller of the pump is constructed. In the case of a positive displacement pump, the piston acts as the impeller.
- 'ImpellerSeal': Material from which the impeller shaft seal of the pump is constructed.
Port Use Definition
The distribution ports relating to the IfcPumpType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcPump for standard port definitions.
"
3347;IfcDamperType;"
The flow controller type IfcDamperType defines commonly shared information for occurrences of dampers. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a damper specification (i.e. the specific product information, that is common to all occurrences of that product type). Damper types may be exchanged without being already assigned to occurrences.
Occurrences of IfcDamperType are represented by instances of IfcDamper.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowControllerType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
The following property set definitions are applicable to this entity according to the PredefinedType attribute:
Material Use Definition
The material of the IfcDamperType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Blade': The material from which the damper blades are constructed.
- 'Frame': The material from which the damper frame is constructed.
- 'Seal': The material from which the damper seals are constructed.
Port Use Definition
The distribution ports relating to the IfcDamperType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcDamper for standard port definitions.
"
3364;IfcAirTerminalBoxType;"
The flow controller type IfcAirTerminalBoxType defines commonly shared information for occurrences of air boxes. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a air box specification (i.e. the specific product information, that is common to all occurrences of that product type). Air Box types may be exchanged without being already assigned to occurrences.
Occurrences of IfcAirTerminalBoxType are represented by instances of IfcAirTerminalBox.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowControllerType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcAirTerminalBoxType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Body': The primary material from which the object is constructed.
Port Use Definition
The distribution ports relating to the IfcAirTerminalBoxType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcAirTerminalBox for standard port definitions.
"
3373;IfcValveType;"
The flow controller type IfcValveType defines commonly shared information for occurrences of valves. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a valve specification (i.e. the specific product information, that is common to all occurrences of that product type). Valve types may be exchanged without being already assigned to occurrences.
Occurrences of IfcValveType are represented by instances of IfcValve.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowControllerType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
The following property set definitions are applicable to this entity according to the PredefinedType attribute:
Material Use Definition
The material of the IfcValveType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Body': The primary material from which the object is constructed.
- 'Operation': Material from which the operating mechanism (gate, globe, plug, needle, clack etc.) of the valve is constructed.
Port Use Definition
The distribution ports relating to the IfcValveType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcValve for standard port definitions.
"
3400;IfcFlowMeterType;"
The flow controller type IfcFlowMeterType defines commonly shared information for occurrences of flow meters. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a flow meter specification (i.e. the specific product information, that is common to all occurrences of that product type). Flow Meter types may be exchanged without being already assigned to occurrences.
Occurrences of IfcFlowMeterType are represented by instances of IfcFlowMeter.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowControllerType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
The following property set definitions are applicable to this entity according to the PredefinedType attribute:
Material Use Definition
The material of the IfcFlowMeterType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Casing': Material from which the casing is constructed.
Port Use Definition
The distribution ports relating to the IfcFlowMeterType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcFlowMeter for standard port definitions.
"
3410;IfcDuctFittingType;"
The flow fitting type IfcDuctFittingType defines commonly shared information for occurrences of duct fittings. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a duct fitting specification (i.e. the specific product information, that is common to all occurrences of that product type). Duct Fitting types may be exchanged without being already assigned to occurrences.
Occurrences of IfcDuctFittingType are represented by instances of IfcDuctFitting.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowFittingType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcDuctFittingType is defined by IfcMaterialProfileSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialProfileSet.MaterialProfiles[n].Name shall be used:
- 'Body': Material from which the duct fitting is constructed.
- 'Coating': The outer coating, if applicable.
- 'Insulation': The insulating wrapping, if applicable.
- 'Lining': The inner lining, if applicable.
Port Use Definition
The distribution ports relating to the IfcDuctFittingType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcDuctFitting for standard port definitions.
"
3423;IfcPipeFittingType;"
The flow fitting type IfcPipeFittingType defines commonly shared information for occurrences of pipe fittings. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a pipe fitting specification (i.e. the specific product information, that is common to all occurrences of that product type). Pipe Fitting types may be exchanged without being already assigned to occurrences.
Occurrences of IfcPipeFittingType are represented by instances of IfcPipeFitting.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowFittingType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcPipeFittingType is defined by IfcMaterialProfileSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialProfileSet.MaterialProfiles[n].Name shall be used:
- 'Body': Material from which the pipe fitting is constructed.
- 'Coating': The outer coating, if applicable.
- 'Insulation': The insulating wrapping, if applicable.
- 'Lining': The inner lining, if applicable.
Port Use Definition
The distribution ports relating to the IfcPipeFittingType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcPipeFitting for standard port definitions.
"
3436;IfcTankType;"
The flow storage device type IfcTankType defines commonly shared information for occurrences of tanks. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a tank specification (i.e. the specific product information, that is common to all occurrences of that product type). Tank types may be exchanged without being already assigned to occurrences.
Occurrences of IfcTankType are represented by instances of IfcTank.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowStorageDeviceType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
The following property set definitions are applicable to this entity according to the PredefinedType attribute:
Material Use Definition
The material of the IfcTankType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Body': The primary material from which the object is constructed.
Port Use Definition
The distribution ports relating to the IfcTankType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcTank for standard port definitions.
"
3449;IfcDuctSilencerType;"
The flow treatment device type IfcDuctSilencerType defines commonly shared information for occurrences of duct silencers. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a duct silencer specification (i.e. the specific product information, that is common to all occurrences of that product type). Duct Silencer types may be exchanged without being already assigned to occurrences.
Occurrences of IfcDuctSilencerType are represented by instances of IfcDuctSilencer.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowTreatmentDeviceType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcDuctSilencerType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Body': The primary material from which the object is constructed.
Port Use Definition
The distribution ports relating to the IfcDuctSilencerType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcDuctSilencer for standard port definitions.
"
3458;IfcFilterType;"
The flow treatment device type IfcFilterType defines commonly shared information for occurrences of filters. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a filter specification (i.e. the specific product information, that is common to all occurrences of that product type). Filter types may be exchanged without being already assigned to occurrences.
Occurrences of IfcFilterType are represented by instances of IfcFilter.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowTreatmentDeviceType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
The following property set definitions are applicable to this entity according to the PredefinedType attribute:
Material Use Definition
The material of the IfcFilterType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Media': The material that is used for filtering particulates from the fluid.
Port Use Definition
The distribution ports relating to the IfcFilterType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcFilter for standard port definitions.
"
3470;IfcPipeSegmentType;"
The flow segment type IfcPipeSegmentType defines commonly shared information for occurrences of pipe segments. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a pipe segment specification (i.e. the specific product information, that is common to all occurrences of that product type). Pipe Segment types may be exchanged without being already assigned to occurrences.
Occurrences of IfcPipeSegmentType are represented by instances of IfcPipeSegment.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowSegmentType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
The following property set definitions are applicable to this entity according to the PredefinedType attribute:
Material Use Definition
The material of the IfcPipeSegmentType is defined by IfcMaterialProfileSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialProfileSet.MaterialProfiles[n].Name shall be used:
- 'Body': Material from which the pipe segment is constructed.
- 'Coating': The outer coating, if applicable.
- 'Insulation': The insulating wrapping, if applicable.
- 'Lining': The inner lining, if applicable.
Port Use Definition
The distribution ports relating to the IfcPipeSegmentType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcPipeSegment for standard port definitions.
"
3481;IfcDuctSegmentType;"
The flow segment type IfcDuctSegmentType defines commonly shared information for occurrences of duct segments. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a duct segment specification (i.e. the specific product information, that is common to all occurrences of that product type). Duct Segment types may be exchanged without being already assigned to occurrences.
Occurrences of IfcDuctSegmentType are represented by instances of IfcDuctSegment.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowSegmentType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcDuctSegmentType is defined by IfcMaterialProfileSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialProfileSet.MaterialProfiles[n].Name shall be used:
- 'Body': Material from which the duct segment is constructed.
- 'Coating': The outer coating, if applicable.
- 'Insulation': The insulating wrapping, if applicable.
- 'Lining': The inner lining, if applicable.
Port Use Definition
The distribution ports relating to the IfcDuctSegmentType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcDuctSegment for standard port definitions.
"
3489;IfcPipeFitting;"A pipe fitting is a junction or transition in a piping flow distribution system or used to connect pipe segments, resulting changes in flow characteristics to the fluid such as direction or flow rate.
HISTORY New entity in IFC2x4
Type Use Definition
IfcPipeFitting defines the occurrence of any pipe fitting; common information about pipe fitting types is handled by IfcPipeFittingType.
The IfcPipeFittingType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcPipeFittingType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcPipeFittingType has ports or aggregated elements, such objects are reflected at the IfcPipeFitting occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcPipeFittingType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcPipeFittingType.HasPropertySets.
If both are given, then the properties directly defined at IfcPipeFitting override the properties defined at IfcPipeFittingType.
Refer to the documentation at the supertype IfcFlowFitting and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcPipeFitting is defined by IfcMaterialProfileSetUsage or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcPipeFittingType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialProfileSet.MaterialProfiles[n].Name shall be used:
- Body: Material from which the pipe fitting is constructed.
- Coating: The outer coating, if applicable.
- Insulation: The insulating wrapping, if applicable.
- Lining: The inner lining, if applicable.
Port Use Definition
The distribution ports relating to the IfcPipeFitting are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the pipe fitting occurrence is defined by IfcPipeFittingType, then the port occurrences must reflect those defined at the IfcPipeFittingType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcPipeFitting PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
Figure 227 illustrates pipe fitting port use.
![]() |
Figure 227 — Pipe fitting port use |
"
3493;IfcDuctFitting;"A duct fitting is a junction or transition in a ducted flow distribution system or used to connect duct segments, resulting changes in flow characteristics to the fluid such as direction and flow rate.
HISTORY New entity in IFC2x4
Type Use Definition
IfcDuctFitting defines the occurrence of any duct fitting; common information about duct fitting types is handled by IfcDuctFittingType.
The IfcDuctFittingType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcDuctFittingType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcDuctFittingType has ports or aggregated elements, such objects are reflected at the IfcDuctFitting occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcDuctFittingType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcDuctFittingType.HasPropertySets.
If both are given, then the properties directly defined at IfcDuctFitting override the properties defined at IfcDuctFittingType.
Refer to the documentation at the supertype IfcFlowFitting and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcDuctFitting is defined by IfcMaterialProfileSetUsage or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcDuctFittingType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialProfileSet.MaterialProfiles[n].Name shall be used:
- Body: Material from which the duct fitting is constructed.
- Coating: The outer coating, if applicable.
- Insulation: The insulating wrapping, if applicable.
- Lining: The inner lining, if applicable.
Port Use Definition
The distribution ports relating to the IfcDuctFitting are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the duct fitting occurrence is defined by IfcDuctFittingType, then the port occurrences must reflect those defined at the IfcDuctFittingType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcDuctFitting PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
Figure 221 illustrates duct fitting port use.
![]() |
Figure 221 — Duct fitting port use |
"
3497;IfcPipeSegment;"A pipe segment is used to typically join two sections of a piping network.
HISTORY New entity in IFC2x4
Type Use Definition
IfcPipeSegment defines the occurrence of any pipe segment; common information about pipe segment types is handled by IfcPipeSegmentType.
The IfcPipeSegmentType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcPipeSegmentType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcPipeSegmentType has ports or aggregated elements, such objects are reflected at the IfcPipeSegment occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcPipeSegmentType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcPipeSegmentType.HasPropertySets.
If both are given, then the properties directly defined at IfcPipeSegment override the properties defined at IfcPipeSegmentType.
Refer to the documentation at the supertype IfcFlowSegment and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcPipeSegment is defined by IfcMaterialProfileSetUsage or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcPipeSegmentType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialProfileSet.MaterialProfiles[n].Name shall be used:
- Body: Material from which the duct fitting is constructed.
- Coating: The outer coating, if applicable.
- Insulation: The insulating wrapping, if applicable.
- Lining: The inner lining, if applicable.
Port Use Definition
The distribution ports relating to the IfcPipeSegment are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the pipe segment occurrence is defined by IfcPipeSegmentType, then the port occurrences must reflect those defined at the IfcPipeSegmentType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcPipeSegment PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
Figure 228 illustrates pipe segment port use.
![]() |
Figure 228 — Pipe segment port use |
"
3501;IfcDuctSegment;"A duct segment is used to typically join two sections of duct network.
HISTORY New entity in IFC2x4
Type Use Definition
IfcDuctSegment defines the occurrence of any duct segment; common information about duct segment types is handled by IfcDuctSegmentType.
The IfcDuctSegmentType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcDuctSegmentType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcDuctSegmentType has ports or aggregated elements, such objects are reflected at the IfcDuctSegment occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcDuctSegmentType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcDuctSegmentType.HasPropertySets.
If both are given, then the properties directly defined at IfcDuctSegment override the properties defined at IfcDuctSegmentType.
Refer to the documentation at the supertype IfcFlowSegment and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcDuctSegment is defined by IfcMaterialProfileSetUsage or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcDuctSegmentType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialProfileSet.MaterialProfiles[n].Name shall be used:
- Body: Material from which the duct fitting is constructed.
- Coating: The outer coating, if applicable.
- Insulation: The insulating wrapping, if applicable.
- Lining: The inner lining, if applicable.
Port Use Definition
The distribution ports relating to the IfcDuctSegment are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the duct segment occurrence is defined by IfcDuctSegmentType, then the port occurrences must reflect those defined at the IfcDuctSegmentType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcDuctSegment PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
Figure 222 illustrates duct segment port use.
![]() |
Figure 222 — Duct segment port use |
"
3505;IfcFilter;"A filter is an apparatus used to remove particulate or gaseous matter from fluids and gases.
HISTORY New entity in IFC2x4
Type Use Definition
IfcFilter defines the occurrence of any filter; common information about filter types is handled by IfcFilterType.
The IfcFilterType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcFilterType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcFilterType has ports or aggregated elements, such objects are reflected at the IfcFilter occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcFilterType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcFilterType.HasPropertySets.
If both are given, then the properties directly defined at IfcFilter override the properties defined at IfcFilterType.
Refer to the documentation at the supertype IfcFlowTreatmentDevice and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcFilter is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcFilterType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Frame: The material used to construct the filter housing.
- Media: The material that is used for filtering particulates.
Port Use Definition
The distribution ports relating to the IfcFilter are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the filter occurrence is defined by IfcFilterType, then the port occurrences must reflect those defined at the IfcFilterType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcFilter PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
Figure 225 illustrates filter port use.
![]() |
Figure 225 — Filter port use |
"
3509;IfcDuctSilencer;"A duct silencer is a device that is typically installed inside a duct distribution system for the purpose of reducing the noise levels from air movement, fan noise, etc. in the adjacent space or downstream of the duct silencer device.
HISTORY New entity in IFC2x4
Type Use Definition
IfcDuctSilencer defines the occurrence of any duct silencer; common information about duct silencer types is handled by IfcDuctSilencerType.
The IfcDuctSilencerType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcDuctSilencerType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcDuctSilencerType has ports or aggregated elements, such objects are reflected at the IfcDuctSilencer occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcDuctSilencerType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcDuctSilencerType.HasPropertySets.
If both are given, then the properties directly defined at IfcDuctSilencer override the properties defined at IfcDuctSilencerType.
Refer to the documentation at the supertype IfcFlowTreatmentDevice and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcDuctSilencer is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcDuctSilencerType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Body: The primary material from which the object is constructed.
Port Use Definition
The distribution ports relating to the IfcDuctSilencer are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the duct silencer occurrence is defined by IfcDuctSilencerType, then the port occurrences must reflect those defined at the IfcDuctSilencerType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcDuctSilencer PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
"
3513;IfcCompressor;"A compressor is a device that compresses a fluid typically used in a refrigeration circuit.
HISTORY New entity in IFC2x4
Type Use Definition
IfcCompressor defines the occurrence of any compressor; common information about compressor types is handled by IfcCompressorType.
The IfcCompressorType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcCompressorType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcCompressorType has ports or aggregated elements, such objects are reflected at the IfcCompressor occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcCompressorType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcCompressorType.HasPropertySets.
If both are given, then the properties directly defined at IfcCompressor override the properties defined at IfcCompressorType.
Refer to the documentation at the supertype IfcFlowMovingDevice and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcCompressor is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcCompressorType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Body: The primary material from which the object is constructed.
- Refrigerant: Refrigerant material.
Port Use Definition
The distribution ports relating to the IfcCompressor are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the compressor occurrence is defined by IfcCompressorType, then the port occurrences must reflect those defined at the IfcCompressorType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcCompressor PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
- RefrigerantIn (REFRIGERATION, SINK): Uncompressed vapor refrigerant entering the compressor.
- RefrigerantOut (REFRIGERATION, SOURCE): Compressed vapor refrigerant leaving the compressor.
Figure 217 illustrates compressor port use.
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Figure 217 — Compressor port use |
"
3517;IfcFan;"A fan is a device which imparts mechanical work on a gas. A typical usage of a fan is to induce airflow in a building services air distribution system.
HISTORY New entity in IFC2x4
Type Use Definition
IfcFan defines the occurrence of any fan; common information about fan types is handled by IfcFanType.
The IfcFanType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcFanType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcFanType has ports or aggregated elements, such objects are reflected at the IfcFan occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcFanType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcFanType.HasPropertySets.
If both are given, then the properties directly defined at IfcFan override the properties defined at IfcFanType.
Refer to the documentation at the supertype IfcFlowMovingDevice and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcFan is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcFanType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Frame: The material used to construct the fan housing.
- Wheel: The material used to construct the fan wheel.
Port Use Definition
The distribution ports relating to the IfcFan are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the fan occurrence is defined by IfcFanType, then the port occurrences must reflect those defined at the IfcFanType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcFan PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
Figure 224 illustrates fan port use.
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Figure 224 — Fan port use |
"
3521;IfcPump;"A pump is a device which imparts mechanical work on fluids or slurries to move them through a channel or pipeline. A typical use of a pump is to circulate chilled water or heating hot water in a building services distribution system.
HISTORY New entity in IFC2x4
Type Use Definition
IfcPump defines the occurrence of any pump; common information about pump types is handled by IfcPumpType.
The IfcPumpType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcPumpType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcPumpType has ports or aggregated elements, such objects are reflected at the IfcPump occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcPumpType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcPumpType.HasPropertySets.
If both are given, then the properties directly defined at IfcPump override the properties defined at IfcPumpType.
Refer to the documentation at the supertype IfcFlowMovingDevice and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcPump is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcPumpType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Body: The primary material from which the object is constructed.
- Impeller: Material from which the impeller of the pump is constructed. In the case of a positive displacement pump, the piston acts as the impeller.
- Seal: Material from which the impeller shaft seal of the pump is constructed.
Port Use Definition
The distribution ports relating to the IfcPump are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the pump occurrence is defined by IfcPumpType, then the port occurrences must reflect those defined at the IfcPumpType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcPump PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
Figure 229 illustrates pump port use.
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Figure 229 — Pump port use |
"
3525;IfcAirTerminal;"An air terminal is a terminating or origination point for the transfer of air between distribution system(s) and one or more spaces. It can also be used for the transfer of air between adjacent spaces.
HISTORY New entity in IFC2x4
Type Use Definition
IfcAirTerminal defines the occurrence of any air terminal; common information about air terminal types is handled by IfcAirTerminalType.
The IfcAirTerminalType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcAirTerminalType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcAirTerminalType has ports or aggregated elements, such objects are reflected at the IfcAirTerminal occurrence using the IfcRelDefinesByObject relationship.
Figure 210 illustrates air terminal type use.
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Figure 210 — Air terminal type use |
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcAirTerminalType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcAirTerminalType.HasPropertySets.
If both are given, then the properties directly defined at IfcAirTerminal override the properties defined at IfcAirTerminalType.
Refer to the documentation at the supertype IfcFlowTerminal and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcAirTerminal is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcAirTerminalType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Body: The primary material from which the object is constructed.
Port Use Definition
The distribution ports relating to the IfcAirTerminal are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the air terminal occurrence is defined by IfcAirTerminalType, then the port occurrences must reflect those defined at the IfcAirTerminalType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcAirTerminal PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
Figure 211 illustrates air terminal port use.
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Figure 211 — Air terminal port use |
"
3536;IfcSpaceHeater;"Space heaters utilize a combination of radiation and/or natural convection using a heating source such as electricity, steam or hot water to heat a limited space or area. Examples of space heaters include radiators, convectors, baseboard and finned-tube heaters.
IfcUnitaryEquipment should be used for packaged units supporting a combination of heating, cooling, and/or dehumidification; IfcCoil should be used for coil-based floor heating.
HISTORY New entity in IFC2x4
Type Use Definition
IfcSpaceHeater defines the occurrence of any space heater; common information about space heater types is handled by IfcSpaceHeaterType.
The IfcSpaceHeaterType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcSpaceHeaterType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcSpaceHeaterType has ports or aggregated elements, such objects are reflected at the IfcSpaceHeater occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcSpaceHeaterType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcSpaceHeaterType.HasPropertySets.
If both are given, then the properties directly defined at IfcSpaceHeater override the properties defined at IfcSpaceHeaterType.
Refer to the documentation at the supertype IfcFlowTerminal and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcSpaceHeater is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcSpaceHeaterType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Body: The primary material from which the object is constructed.
Port Use Definition
The distribution ports relating to the IfcSpaceHeater are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the space heater occurrence is defined by IfcSpaceHeaterType, then the port occurrences must reflect those defined at the IfcSpaceHeaterType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcSpaceHeater PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
Figure 230 illustrates space heater port use.
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Figure 230 — Space heater port use |
"
3545;IfcMedicalDevice;"A medical device is attached to a medical piping system and operates upon medical gases to perform a specific function. Medical gases include medical air, medical vacuum, oxygen, carbon dioxide, nitrogen, and nitrous oxide.
Outlets for medical gasses should use IfcValve with PredefinedType equal to GASTAP, containing an IfcDistributionPort with FlowDirection=SINK and PredefinedType equal to COMPRESSEDAIR, VACUUM, or CHEMICAL, and having property sets on the port further indicating the gas type and pressure. Tanks for medical gasses should use IfcTank with PredefinedType equal to PRESSUREVESSEL, containing an IfcDistributionPort with FlowDirection=SOURCE and PredefinedType=CHEMICAL, and having property sets on the port further indicating the gas type and pressure range.
HISTORY New entity in IFC2x4
Type Use Definition
IfcMedicalDevice defines the occurrence of any medical device; common information about medical device types is handled by IfcMedicalDeviceType.
The IfcMedicalDeviceType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcMedicalDeviceType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcMedicalDeviceType has ports or aggregated elements, such objects are reflected at the IfcMedicalDevice occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcMedicalDeviceType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcMedicalDeviceType.HasPropertySets.
If both are given, then the properties directly defined at IfcMedicalDevice override the properties defined at IfcMedicalDeviceType.
Refer to the documentation at the supertype IfcFlowTerminal and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcMedicalDevice is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcMedicalDeviceType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Body: The primary material from which the object is constructed.
Port Use Definition
The distribution ports relating to the IfcMedicalDevice are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the medical device occurrence is defined by IfcMedicalDeviceType, then the port occurrences must reflect those defined at the IfcMedicalDeviceType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcMedicalDevice PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
"
3557;IfcAirTerminalBox;"An air terminal box typically participates in an HVAC duct distribution system and is used to control or modulate the amount of air delivered to its downstream ductwork. An air terminal box type is often referred to as an ""air flow regulator"".
HISTORY New entity in IFC2x4
Type Use Definition
IfcAirTerminalBox defines the occurrence of any air terminal box; common information about air terminal box types is handled by IfcAirTerminalBoxType.
The IfcAirTerminalBoxType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcAirTerminalBoxType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcAirTerminalBoxType has ports or aggregated elements, such objects are reflected at the IfcAirTerminalBox occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcAirTerminalBoxType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcAirTerminalBoxType.HasPropertySets.
If both are given, then the properties directly defined at IfcAirTerminalBox override the properties defined at IfcAirTerminalBoxType.
Refer to the documentation at the supertype IfcFlowController and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcAirTerminalBox is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcAirTerminalBoxType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Body: The primary material from which the object is constructed.
Port Use Definition
The distribution ports relating to the IfcAirTerminalBox are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the air terminal box occurrence is defined by IfcAirTerminalBoxType, then the port occurrences must reflect those defined at the IfcAirTerminalBoxType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcAirTerminalBox PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
"
3561;IfcDamper;"A damper typically participates in an HVAC duct distribution system and is used to control or modulate the flow of air.
HISTORY New entity in IFC2x4
Type Use Definition
IfcDamper defines the occurrence of any damper; common information about damper types is handled by IfcDamperType.
The IfcDamperType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcDamperType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcDamperType has ports or aggregated elements, such objects are reflected at the IfcDamper occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcDamperType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcDamperType.HasPropertySets.
If both are given, then the properties directly defined at IfcDamper override the properties defined at IfcDamperType.
Refer to the documentation at the supertype IfcFlowController and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcDamper is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcDamperType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Blade: The material from which the damper blades are constructed.
- Frame: The material from which the damper frame is constructed.
- Seal: The material from which the damper seals are constructed.
Connection Use Definition
The IfcDamper may be connected to other objects as follows using the indicated relationship:
Port Use Definition
The distribution ports relating to the IfcDamper are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the damper occurrence is defined by IfcDamperType, then the port occurrences must reflect those defined at the IfcDamperType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcDamper PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
Figure 220 illustrates damper port use.
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Figure 220 — Damper port use |
"
3565;IfcFlowMeter;"A flow meter is a device that is used to measure the flow rate in a system.
HISTORY New entity in IFC2x4
Type Use Definition
IfcFlowMeter defines the occurrence of any flow meter; common information about flow meter types is handled by IfcFlowMeterType.
The IfcFlowMeterType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcFlowMeterType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcFlowMeterType has ports or aggregated elements, such objects are reflected at the IfcFlowMeter occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcFlowMeterType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcFlowMeterType.HasPropertySets.
If both are given, then the properties directly defined at IfcFlowMeter override the properties defined at IfcFlowMeterType.
Refer to the documentation at the supertype IfcFlowController and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcFlowMeter is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcFlowMeterType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Body: The primary material from which the object is constructed.
Port Use Definition
The distribution ports relating to the IfcFlowMeter are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the flow meter occurrence is defined by IfcFlowMeterType, then the port occurrences must reflect those defined at the IfcFlowMeterType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcFlowMeter PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
Figure 226 illustrates flow meter port use.
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Figure 226 — Flow meter port use |
"
3569;IfcValve;"A valve is used in a building services piping distribution system to control or modulate the flow of the fluid.
HISTORY New entity in IFC2x4
Type Use Definition
IfcValve defines the occurrence of any valve; common information about valve types is handled by IfcValveType.
The IfcValveType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcValveType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcValveType has ports or aggregated elements, such objects are reflected at the IfcValve occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcValveType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcValveType.HasPropertySets.
If both are given, then the properties directly defined at IfcValve override the properties defined at IfcValveType.
Refer to the documentation at the supertype IfcFlowController and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcValve is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcValveType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Body: The primary material from which the object is constructed.
- Operation: Material from which the operating mechanism (such as gate, globe, plug, needle, or clack) of the valve is constructed.
Connection Use Definition
The IfcValve may be connected to other objects as follows using the indicated relationship:
Port Use Definition
The distribution ports relating to the IfcValve are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the valve occurrence is defined by IfcValveType, then the port occurrences must reflect those defined at the IfcValveType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcValve PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
Figure 233 illustrates valve port use.
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Figure 233 — Valve port use |
"
3573;IfcTank;"A tank is a vessel or container in which a fluid or gas is stored for later use.
HISTORY New entity in IFC2x4
Type Use Definition
IfcTank defines the occurrence of any tank; common information about tank types is handled by IfcTankType.
The IfcTankType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcTankType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcTankType has ports or aggregated elements, such objects are reflected at the IfcTank occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcTankType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcTankType.HasPropertySets.
If both are given, then the properties directly defined at IfcTank override the properties defined at IfcTankType.
Refer to the documentation at the supertype IfcFlowStorageDevice and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcTank is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcTankType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Body: The primary material from which the object is constructed.
Port Use Definition
The distribution ports relating to the IfcTank are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the tank occurrence is defined by IfcTankType, then the port occurrences must reflect those defined at the IfcTankType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcTank PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
"
3577;IfcAirToAirHeatRecovery;"An air-to-air heat recovery device employs a counter-flow heat exchanger between inbound and outbound air flow. It is typically used to transfer heat from warmer air in one chamber to cooler air in the second chamber (i.e., typically used to recover heat from the conditioned air being exhausted and the outside air being supplied to a building), resulting in energy savings from reduced heating (or cooling) requirements.
HISTORY New entity in IFC2x4
Type Use Definition
IfcAirToAirHeatRecovery defines the occurrence of any air to air heat recovery; common information about air to air heat recovery types is handled by IfcAirToAirHeatRecoveryType.
The IfcAirToAirHeatRecoveryType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcAirToAirHeatRecoveryType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcAirToAirHeatRecoveryType has ports or aggregated elements, such objects are reflected at the IfcAirToAirHeatRecovery occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcAirToAirHeatRecoveryType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcAirToAirHeatRecoveryType.HasPropertySets.
If both are given, then the properties directly defined at IfcAirToAirHeatRecovery override the properties defined at IfcAirToAirHeatRecoveryType.
Refer to the documentation at the supertype IfcEnergyConversionDevice and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcAirToAirHeatRecovery is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcAirToAirHeatRecoveryType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Body: The primary material from which the object is constructed.
- Media: The primary media material used for heat transfer.
Port Use Definition
The distribution ports relating to the IfcAirToAirHeatRecovery are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the air to air heat recovery occurrence is defined by IfcAirToAirHeatRecoveryType, then the port occurrences must reflect those defined at the IfcAirToAirHeatRecoveryType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcAirToAirHeatRecovery PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
"
3581;IfcBoiler;"A boiler is a closed, pressure-rated vessel in which water or other fluid is heated using an energy source such as natural gas, heating oil, or electricity. The fluid in the vessel is then circulated out of the boiler for use in various processes or heating applications.
IfcBoiler is a vessel solely used for heating of water or other fluids. Storage vessels, such as for drinking water storage are considered as tanks and use the IfcTank entity.
HISTORY New entity in IFC2x4
Type Use Definition
IfcBoiler defines the occurrence of any boiler; common information about boiler types is handled by IfcBoilerType.
The IfcBoilerType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcBoilerType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcBoilerType has ports or aggregated elements, such objects are reflected at the IfcBoiler occurrence using the IfcRelDefinesByObject relationship.
Figure 212 illustrates boiler type use.
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Figure 212 — Boiler type use |
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcBoilerType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcBoilerType.HasPropertySets.
If both are given, then the properties directly defined at IfcBoiler override the properties defined at IfcBoilerType.
Refer to the documentation at the supertype IfcEnergyConversionDevice and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcBoiler is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcBoilerType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Body: The primary material from which the object is constructed.
Port Use Definition
The distribution ports relating to the IfcBoiler are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the boiler occurrence is defined by IfcBoilerType, then the port occurrences must reflect those defined at the IfcBoilerType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcBoiler PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
Figure 213 illustrates boiler port use.
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Figure 213 — Boiler port use |
"
3585;IfcBurner;"A burner is a device that converts fuel into heat through combustion. It includes gas, oil, and wood burners.
HISTORY New entity in IFC2x4
Type Use Definition
IfcBurner defines the occurrence of any burner; common information about burner types is handled by IfcBurnerType.
The IfcBurnerType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcBurnerType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcBurnerType has ports or aggregated elements, such objects are reflected at the IfcBurner occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcBurnerType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcBurnerType.HasPropertySets.
If both are given, then the properties directly defined at IfcBurner override the properties defined at IfcBurnerType.
Refer to the documentation at the supertype IfcEnergyConversionDevice and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcBurner is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcBurnerType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Body: The primary material from which the object is constructed.
- Fuel: Material designed to be burned.
Port Use Definition
The distribution ports relating to the IfcBurner are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the burner occurrence is defined by IfcBurnerType, then the port occurrences must reflect those defined at the IfcBurnerType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcBurner PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
- Gas (GAS, SINK): Gas inlet for burner.
"
3589;IfcChiller;"A chiller is a device used to remove heat from a liquid via a vapor-compression or absorption refrigeration cycle to cool a fluid, typically water or a mixture of water and glycol. The chilled fluid is then used to cool and dehumidify air in a building.
HISTORY New entity in IFC2x4
Type Use Definition
IfcChiller defines the occurrence of any chiller; common information about chiller types is handled by IfcChillerType.
The IfcChillerType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcChillerType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcChillerType has ports or aggregated elements, such objects are reflected at the IfcChiller occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcChillerType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcChillerType.HasPropertySets.
If both are given, then the properties directly defined at IfcChiller override the properties defined at IfcChillerType.
Refer to the documentation at the supertype IfcEnergyConversionDevice and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcChiller is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcChillerType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Body: The primary material from which the object is constructed.
- Refrigerant: Refrigerant material.
Composition Use Definition
The IfcChiller may be aggregated into components using IfcRelAggregates where RelatingObject refers to the enclosing IfcChiller and RelatedObjects contains one or more components. Aggregation use is defined for the following predefined types:
- May contain IfcDistributionElement components. Chillers may aggregate distribution flow elements forming a refrigeration cycle (compressor, condenser, valve, evaporator), as well as control elements.
Figure 214 illustrates chiller composition use.
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Figure 214 — Chiller composition use |
Port Use Definition
The distribution ports relating to the IfcChiller are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the chiller occurrence is defined by IfcChillerType, then the port occurrences must reflect those defined at the IfcChillerType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcChiller PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
Figure 215 illustrates chiller port use.
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Figure 215 — Chiller port use |
"
3593;IfcCoil;"A coil is a device used to provide heat transfer between non-mixing media. A common example is a cooling coil, which utilizes a finned coil in which circulates chilled water, antifreeze, or refrigerant that is used to remove heat from air moving across the surface of the coil. A coil may be used either for heating or cooling purposes by placing a series of tubes (the coil) carrying a heating or cooling fluid into an airstream. The coil may be constructed from tubes bundled in a serpentine form or from finned tubes that give a extended heat transfer surface.
Coils may also be used for non-airflow cases such as embedded in a floor slab.
HISTORY New entity in IFC2x4
Type Use Definition
IfcCoil defines the occurrence of any coil; common information about coil types is handled by IfcCoilType.
The IfcCoilType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcCoilType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcCoilType has ports or aggregated elements, such objects are reflected at the IfcCoil occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcCoilType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcCoilType.HasPropertySets.
If both are given, then the properties directly defined at IfcCoil override the properties defined at IfcCoilType.
Refer to the documentation at the supertype IfcEnergyConversionDevice and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcCoil is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcCoilType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Body: The primary material from which the object is constructed.
Port Use Definition
The distribution ports relating to the IfcCoil are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the coil occurrence is defined by IfcCoilType, then the port occurrences must reflect those defined at the IfcCoilType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcCoil PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
Figure 216 illustrates coil port use.
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Figure 216 — Coil port use |
"
3597;IfcCondenser;"A condenser is a device that is used to dissipate heat, typically by condensing a substance such as a refrigerant from its gaseous to its liquid state.
HISTORY New entity in IFC2x4
Type Use Definition
IfcCondenser defines the occurrence of any condenser; common information about condenser types is handled by IfcCondenserType.
The IfcCondenserType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcCondenserType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcCondenserType has ports or aggregated elements, such objects are reflected at the IfcCondenser occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcCondenserType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcCondenserType.HasPropertySets.
If both are given, then the properties directly defined at IfcCondenser override the properties defined at IfcCondenserType.
Refer to the documentation at the supertype IfcEnergyConversionDevice and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcCondenser is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcCondenserType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Body: The primary material from which the object is constructed.
- Refrigerant: Refrigerant material.
Port Use Definition
The distribution ports relating to the IfcCondenser are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the condenser occurrence is defined by IfcCondenserType, then the port occurrences must reflect those defined at the IfcCondenserType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcCondenser PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
Figure 218 illustrates condenser port use.
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Figure 218 — Condenser port use |
"
3601;IfcCooledBeam;"A cooled beam (or chilled beam) is a device typically used to cool air by circulating a fluid such as chilled water through exposed finned tubes above a space. Typically mounted overhead near or within a ceiling, the cooled beam uses convection to cool the space below it by acting as a heat sink for the naturally rising warm air of the space. Once cooled, the air naturally drops back to the floor where the cycle begins again.
HISTORY New entity in IFC2x4
Type Use Definition
IfcCooledBeam defines the occurrence of any cooled beam; common information about cooled beam types is handled by IfcCooledBeamType.
The IfcCooledBeamType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcCooledBeamType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcCooledBeamType has ports or aggregated elements, such objects are reflected at the IfcCooledBeam occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcCooledBeamType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcCooledBeamType.HasPropertySets.
If both are given, then the properties directly defined at IfcCooledBeam override the properties defined at IfcCooledBeamType.
Refer to the documentation at the supertype IfcEnergyConversionDevice and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcCooledBeam is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcCooledBeamType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Body: The primary material from which the object is constructed.
Port Use Definition
The distribution ports relating to the IfcCooledBeam are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the cooled beam occurrence is defined by IfcCooledBeamType, then the port occurrences must reflect those defined at the IfcCooledBeamType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcCooledBeam PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
"
3605;IfcCoolingTower;"A cooling tower is a device which rejects heat to ambient air by circulating a fluid such as water through it to reduce its temperature by partial evaporation.
HISTORY New entity in IFC2x4
Type Use Definition
IfcCoolingTower defines the occurrence of any cooling tower; common information about cooling tower types is handled by IfcCoolingTowerType.
The IfcCoolingTowerType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcCoolingTowerType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcCoolingTowerType has ports or aggregated elements, such objects are reflected at the IfcCoolingTower occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcCoolingTowerType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcCoolingTowerType.HasPropertySets.
If both are given, then the properties directly defined at IfcCoolingTower override the properties defined at IfcCoolingTowerType.
Refer to the documentation at the supertype IfcEnergyConversionDevice and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcCoolingTower is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcCoolingTowerType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Body: The primary material from which the object is constructed.
- Fill: Fill material.
Composition Use Definition
The IfcCoolingTower may be aggregated into components using IfcRelAggregates where RelatingObject refers to the enclosing IfcCoolingTower and RelatedObjects contains one or more components. Aggregation use is defined for the following predefined types:
Port Use Definition
The distribution ports relating to the IfcCoolingTower are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the cooling tower occurrence is defined by IfcCoolingTowerType, then the port occurrences must reflect those defined at the IfcCoolingTowerType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcCoolingTower PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
Figure 219 illustrates cooling tower port use.
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Figure 219 — Cooling tower port use |
"
3609;IfcEvaporativeCooler;"An evaporative cooler is a device that cools air by saturating it with water vapor.
HISTORY New entity in IFC2x4
Type Use Definition
IfcEvaporativeCooler defines the occurrence of any evaporative cooler; common information about evaporative cooler types is handled by IfcEvaporativeCoolerType.
The IfcEvaporativeCoolerType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcEvaporativeCoolerType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcEvaporativeCoolerType has ports or aggregated elements, such objects are reflected at the IfcEvaporativeCooler occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcEvaporativeCoolerType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcEvaporativeCoolerType.HasPropertySets.
If both are given, then the properties directly defined at IfcEvaporativeCooler override the properties defined at IfcEvaporativeCoolerType.
Refer to the documentation at the supertype IfcEnergyConversionDevice and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcEvaporativeCooler is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcEvaporativeCoolerType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Body: The primary material from which the object is constructed.
- Media: Heat exchanger media material.
Port Use Definition
The distribution ports relating to the IfcEvaporativeCooler are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the evaporative cooler occurrence is defined by IfcEvaporativeCoolerType, then the port occurrences must reflect those defined at the IfcEvaporativeCoolerType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcEvaporativeCooler PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
"
3613;IfcEvaporator;"An evaporator is a device in which a liquid refrigerent is vaporized and absorbs heat from the surrounding fluid.
HISTORY New entity in IFC2x4
Type Use Definition
IfcEvaporator defines the occurrence of any evaporator; common information about evaporator types is handled by IfcEvaporatorType.
The IfcEvaporatorType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcEvaporatorType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcEvaporatorType has ports or aggregated elements, such objects are reflected at the IfcEvaporator occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcEvaporatorType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcEvaporatorType.HasPropertySets.
If both are given, then the properties directly defined at IfcEvaporator override the properties defined at IfcEvaporatorType.
Refer to the documentation at the supertype IfcEnergyConversionDevice and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcEvaporator is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcEvaporatorType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Body: The primary material from which the object is constructed.
- Refrigerant: Refrigerant material.
Port Use Definition
The distribution ports relating to the IfcEvaporator are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the evaporator occurrence is defined by IfcEvaporatorType, then the port occurrences must reflect those defined at the IfcEvaporatorType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcEvaporator PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
Figure 223 illustrates evaporator port use.
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Figure 223 — Evaporator port use |
"
3617;IfcHeatExchanger;"A heat exchanger is a device used to provide heat transfer between non-mixing media such as plate and shell and tube heat exchangers.
IfcHeatExchanger is commonly used on water-side distribution systems to recover energy from a liquid to another liquid (typically water-based), whereas IfcAirToAirHeatRecovery is commonly used on air-side distribution systems to recover energy from a gas to a gas (usually air).
HISTORY New entity in IFC2x4
Type Use Definition
IfcHeatExchanger defines the occurrence of any heat exchanger; common information about heat exchanger types is handled by IfcHeatExchangerType.
The IfcHeatExchangerType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcHeatExchangerType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcHeatExchangerType has ports or aggregated elements, such objects are reflected at the IfcHeatExchanger occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcHeatExchangerType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcHeatExchangerType.HasPropertySets.
If both are given, then the properties directly defined at IfcHeatExchanger override the properties defined at IfcHeatExchangerType.
Refer to the documentation at the supertype IfcEnergyConversionDevice and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcHeatExchanger is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcHeatExchangerType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Body: The primary material from which the object is constructed.
Port Use Definition
The distribution ports relating to the IfcHeatExchanger are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the heat exchanger occurrence is defined by IfcHeatExchangerType, then the port occurrences must reflect those defined at the IfcHeatExchangerType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcHeatExchanger PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
"
3621;IfcHumidifier;"A humidifier is a device that adds moisture into the air.
HISTORY New entity in IFC2x4
Type Use Definition
IfcHumidifier defines the occurrence of any humidifier; common information about humidifier types is handled by IfcHumidifierType.
The IfcHumidifierType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcHumidifierType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcHumidifierType has ports or aggregated elements, such objects are reflected at the IfcHumidifier occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcHumidifierType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcHumidifierType.HasPropertySets.
If both are given, then the properties directly defined at IfcHumidifier override the properties defined at IfcHumidifierType.
Refer to the documentation at the supertype IfcEnergyConversionDevice and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcHumidifier is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcHumidifierType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Body: The primary material from which the object is constructed.
Port Use Definition
The distribution ports relating to the IfcHumidifier are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the humidifier occurrence is defined by IfcHumidifierType, then the port occurrences must reflect those defined at the IfcHumidifierType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcHumidifier PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
"
3625;IfcTubeBundle;"A tube bundle is a device consisting of tubes and bundles of tubes used for heat transfer and contained typically within other energy conversion devices, such as a chiller or coil.
HISTORY New entity in IFC2x4
Type Use Definition
IfcTubeBundle defines the occurrence of any tube bundle; common information about tube bundle types is handled by IfcTubeBundleType.
The IfcTubeBundleType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcTubeBundleType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcTubeBundleType has ports or aggregated elements, such objects are reflected at the IfcTubeBundle occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcTubeBundleType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcTubeBundleType.HasPropertySets.
If both are given, then the properties directly defined at IfcTubeBundle override the properties defined at IfcTubeBundleType.
Refer to the documentation at the supertype IfcEnergyConversionDevice and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcTubeBundle is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcTubeBundleType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Body: The primary material from which the object is constructed.
Port Use Definition
The distribution ports relating to the IfcTubeBundle are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the tube bundle occurrence is defined by IfcTubeBundleType, then the port occurrences must reflect those defined at the IfcTubeBundleType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcTubeBundle PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
"
3629;IfcUnitaryEquipment;"Unitary equipment typically combine a number of components into a single product, such as air handlers, pre-packaged rooftop air-conditioning units, and split systems.
HISTORY New entity in IFC2x4
Type Use Definition
IfcUnitaryEquipment defines the occurrence of any unitary equipment; common information about unitary equipment types is handled by IfcUnitaryEquipmentType.
The IfcUnitaryEquipmentType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcUnitaryEquipmentType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcUnitaryEquipmentType has ports or aggregated elements, such objects are reflected at the IfcUnitaryEquipment occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcUnitaryEquipmentType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcUnitaryEquipmentType.HasPropertySets.
If both are given, then the properties directly defined at IfcUnitaryEquipment override the properties defined at IfcUnitaryEquipmentType.
Refer to the documentation at the supertype IfcEnergyConversionDevice and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcUnitaryEquipment is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcUnitaryEquipmentType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Body: The primary material from which the object is constructed.
Composition Use Definition
The IfcUnitaryEquipment may be aggregated into components using IfcRelAggregates where RelatingObject refers to the enclosing IfcUnitaryEquipment and RelatedObjects contains one or more components. Aggregation use is defined for the following predefined types:
- May contain IfcDistributionElement components. Unitary equipment (air handlers in particular) may elaborate contained elements such as dampers, fans, coils, sensors, actuators, and controllers. Such breakdown provides access to component information and tracking of performance history for embedded elements.
Figure 231 illustrates unitary equipment composition use.
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Figure 231 — Unitary equipment composition use |
Port Use Definition
The distribution ports relating to the IfcUnitaryEquipment are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the unitary equipment occurrence is defined by IfcUnitaryEquipmentType, then the port occurrences must reflect those defined at the IfcUnitaryEquipmentType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcUnitaryEquipment PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
- AIRHANDLER
- ReturnAirIn (AIRCONDITIONING, SINK): Return air entering mixture or exhausted.
- SupplyAirOut (AIRCONDITIONING, SOURCE): Chilled supply air.
- OutsideAirIn (VENTILATION, SINK): Outside air entering mixture.
- ExhaustAirOut (EXHAUST, SOURCE): Exhaust air leaving to outside.
- ChilledWaterIn (CHILLEDWATER, SINK): Chilled water entering cooling coil.
- ChilledWaterOut (CHILLEDWATER, SOURCE): Chilled water leaving cooling coil.
- HeatingIn (HEATING, SINK): Steam entering heating coil.
- HeatingOut (HEATING, SOURCE): Steam leaving heating coil.
- Power (ELECTRICAL, SINK): Electrical power source.
- Control (CONTROL, SINK): Control system communication.
Figure 232 illustrates unitary equipment port use.
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Figure 232 — Unitary equipment port use |
"
3633;IfcEngine;"An engine is a device that converts fuel into mechanical energy through combustion.
HISTORY New entity in IFC2x4
Type Use Definition
IfcEngine defines the occurrence of any engine; common information about engine types is handled by IfcEngineType.
The IfcEngineType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcEngineType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcEngineType has ports or aggregated elements, such objects are reflected at the IfcEngine occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcEngineType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcEngineType.HasPropertySets.
If both are given, then the properties directly defined at IfcEngine override the properties defined at IfcEngineType.
Refer to the documentation at the supertype IfcEnergyConversionDevice and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcEngine is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcEngineType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Body: The primary material from which the object is constructed.
Port Use Definition
The distribution ports relating to the IfcEngine are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the engine occurrence is defined by IfcEngineType, then the port occurrences must reflect those defined at the IfcEngineType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcEngine PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
"
3637;IfcAirTerminalType;"
The flow terminal type IfcAirTerminalType defines commonly shared information for occurrences of air terminals. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a air terminal specification (i.e. the specific product information, that is common to all occurrences of that product type). Air Terminal types may be exchanged without being already assigned to occurrences.
Occurrences of IfcAirTerminalType are represented by instances of IfcAirTerminal.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowTerminalType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcAirTerminalType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Body': The primary material from which the object is constructed.
Port Use Definition
The distribution ports relating to the IfcAirTerminalType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcAirTerminal for standard port definitions.
"
3640;IfcSpaceHeaterType;"
The energy conversion device type IfcSpaceHeaterType defines commonly shared information for occurrences of space heaters. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a space heater specification (i.e. the specific product information, that is common to all occurrences of that product type). Space Heater types may be exchanged without being already assigned to occurrences.
Occurrences of IfcSpaceHeaterType are represented by instances of IfcSpaceHeater.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcEnergyConversionDeviceType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
The following property set definitions are applicable to this entity according to the PredefinedType attribute:
Material Use Definition
The material of the IfcSpaceHeaterType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Body': The primary material from which the object is constructed.
Port Use Definition
The distribution ports relating to the IfcSpaceHeaterType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcSpaceHeater for standard port definitions.
"
3643;IfcMedicalDeviceType;"
The flow terminal type IfcMedicalDeviceType defines commonly shared information for occurrences of medical devices. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a medical device specification (i.e. the specific product information, that is common to all occurrences of that product type). Medical Device types may be exchanged without being already assigned to occurrences.
Occurrences of IfcMedicalDeviceType are represented by instances of IfcMedicalDevice.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowTerminalType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcMedicalDeviceType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Body': The primary material from which the object is constructed.
Port Use Definition
The distribution ports relating to the IfcMedicalDeviceType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcMedicalDevice for standard port definitions.
"
3646;IfcVibrationIsolator;"A vibration isolator is a device used to minimize the effects of vibration transmissibility in a building.
HISTORY New entity in IFC2x4
Type Use Definition
IfcVibrationIsolator defines the occurrence of any vibration isolator; common information about vibration isolator types is handled by IfcVibrationIsolatorType.
The IfcVibrationIsolatorType (if present) may establish the common type name, usage (predefined type), properties, materials, composition, assignments, and representations.
The IfcVibrationIsolatorType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcVibrationIsolatorType has aggregated elements, such objects are reflected at the IfcVibrationIsolator occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcVibrationIsolatorType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcVibrationIsolatorType.HasPropertySets.
If both are given, then the properties directly defined at IfcVibrationIsolator override the properties defined at IfcVibrationIsolatorType.
Refer to the documentation at the supertype IfcElementComponent and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcVibrationIsolator is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcVibrationIsolatorType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Body: The primary material from which the object is constructed.
- Damping: Material from which the damping element of the vibration isolator is constructed.
"
3655;IfcVibrationIsolatorType;"
The element component type IfcVibrationIsolatorType defines commonly shared information for occurrences of vibration isolators. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- applicable assignment of process types
It is used to define a vibration isolator specification (i.e. the specific product information, that is common to all occurrences of that product type). Vibration Isolator types may be exchanged without being already assigned to occurrences.
Occurrences of IfcVibrationIsolatorType are represented by instances of IfcVibrationIsolator.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcElementComponentType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcVibrationIsolatorType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Damping': Material from which the damping element of the vibration isolator is constructed.
"
3659;IfcWasteTerminalType;"
The flow terminal type IfcWasteTerminalType defines commonly shared information for occurrences of waste terminals. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a waste terminal specification (i.e. the specific product information, that is common to all occurrences of that product type). Waste Terminal types may be exchanged without being already assigned to occurrences.
Occurrences of IfcWasteTerminalType are represented by instances of IfcWasteTerminal.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowTerminalType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
The following property set definitions are applicable to this entity according to the PredefinedType attribute:
Material Use Definition
The material of the IfcWasteTerminalType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Body': The primary material from which the object is constructed.
- 'Cover': Material from which the cover or grating is constructed.
Port Use Definition
The distribution ports relating to the IfcWasteTerminalType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcWasteTerminal for standard port definitions.
"
3672;IfcStackTerminalType;"
The flow terminal type IfcStackTerminalType defines commonly shared information for occurrences of stack terminals. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a stack terminal specification (i.e. the specific product information, that is common to all occurrences of that product type). Stack Terminal types may be exchanged without being already assigned to occurrences.
Occurrences of IfcStackTerminalType are represented by instances of IfcStackTerminal.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowTerminalType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Material Use Definition
The material of the IfcStackTerminalType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Body': The primary material from which the object is constructed.
Port Use Definition
The distribution ports relating to the IfcStackTerminalType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcStackTerminal for standard port definitions.
"
3681;IfcSanitaryTerminalType;"
The flow terminal type IfcSanitaryTerminalType defines commonly shared information for occurrences of sanitary terminals. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a sanitary terminal specification (i.e. the specific product information, that is common to all occurrences of that product type). Sanitary Terminal types may be exchanged without being already assigned to occurrences.
Occurrences of IfcSanitaryTerminalType are represented by instances of IfcSanitaryTerminal.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowTerminalType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
The following property set definitions are applicable to this entity according to the PredefinedType attribute:
Material Use Definition
The material of the IfcSanitaryTerminalType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Body': The primary material from which the object is constructed.
Port Use Definition
The distribution ports relating to the IfcSanitaryTerminalType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcSanitaryTerminal for standard port definitions.
"
3697;IfcFireSuppressionTerminalType;"
The flow terminal type IfcFireSuppressionTerminalType defines commonly shared information for occurrences of fire suppression terminals. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a fire suppression terminal specification (i.e. the specific product information, that is common to all occurrences of that product type). Fire Suppression Terminal types may be exchanged without being already assigned to occurrences.
Occurrences of IfcFireSuppressionTerminalType are represented by instances of IfcFireSuppressionTerminal.
HISTORY: New entity in IFC2x2
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowTerminalType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
The following property set definitions are applicable to this entity according to the PredefinedType attribute:
Material Use Definition
The material of the IfcFireSuppressionTerminalType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Body': The primary material from which the object is constructed.
- 'Deflector': The material used to construct the deflector plate.
Port Use Definition
The distribution ports relating to the IfcFireSuppressionTerminalType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcFireSuppressionTerminal for standard port definitions.
"
3708;IfcFireSuppressionTerminal;"A fire suppression terminal has the purpose of delivering a fluid (gas or liquid) that will suppress a fire.
A fire suppression terminal provides for all forms of sprinkler, spreader and other form of terminal that is connected to a pipework system and intended to act in the role of suppressing a fire.
HISTORY New entity in IFC2x4
Type Use Definition
IfcFireSuppressionTerminal defines the occurrence of any fire suppression terminal; common information about fire suppression terminal types is handled by IfcFireSuppressionTerminalType.
The IfcFireSuppressionTerminalType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcFireSuppressionTerminalType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcFireSuppressionTerminalType has ports or aggregated elements, such objects are reflected at the IfcFireSuppressionTerminal occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcFireSuppressionTerminalType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcFireSuppressionTerminalType.HasPropertySets.
If both are given, then the properties directly defined at IfcFireSuppressionTerminal override the properties defined at IfcFireSuppressionTerminalType.
Refer to the documentation at the supertype IfcFlowTerminal and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcFireSuppressionTerminal is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcFireSuppressionTerminalType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Body: The primary material from which the object is constructed.
- Deflector: The material used to construct the deflector plate.
Port Use Definition
The distribution ports relating to the IfcFireSuppressionTerminal are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the fire suppression terminal occurrence is defined by IfcFireSuppressionTerminalType, then the port occurrences must reflect those defined at the IfcFireSuppressionTerminalType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcFireSuppressionTerminal PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
"
3712;IfcSanitaryTerminal;"A sanitary terminal is a fixed appliance or terminal usually supplied with water and used for drinking, cleaning or foul water disposal or that is an item of equipment directly used with such an appliance or terminal.
HISTORY New entity in IFC2x4
Type Use Definition
IfcSanitaryTerminal defines the occurrence of any sanitary terminal; common information about sanitary terminal types is handled by IfcSanitaryTerminalType.
The IfcSanitaryTerminalType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcSanitaryTerminalType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcSanitaryTerminalType has ports or aggregated elements, such objects are reflected at the IfcSanitaryTerminal occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcSanitaryTerminalType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcSanitaryTerminalType.HasPropertySets.
If both are given, then the properties directly defined at IfcSanitaryTerminal override the properties defined at IfcSanitaryTerminalType.
Refer to the documentation at the supertype IfcFlowTerminal and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcSanitaryTerminal is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcSanitaryTerminalType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Body: The primary material from which the object is constructed.
Port Use Definition
The distribution ports relating to the IfcSanitaryTerminal are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the sanitary terminal occurrence is defined by IfcSanitaryTerminalType, then the port occurrences must reflect those defined at the IfcSanitaryTerminalType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcSanitaryTerminal PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
"
3716;IfcStackTerminal;"A stack terminal is placed at the top of a ventilating stack (such as to prevent ingress by birds or rainwater) or rainwater pipe (to act as a collector or hopper for discharge from guttering).
HISTORY New entity in IFC2x4
Type Use Definition
IfcStackTerminal defines the occurrence of any stack terminal; common information about stack terminal types is handled by IfcStackTerminalType.
The IfcStackTerminalType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcStackTerminalType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcStackTerminalType has ports or aggregated elements, such objects are reflected at the IfcStackTerminal occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcStackTerminalType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcStackTerminalType.HasPropertySets.
If both are given, then the properties directly defined at IfcStackTerminal override the properties defined at IfcStackTerminalType.
Refer to the documentation at the supertype IfcFlowTerminal and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcStackTerminal is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcStackTerminalType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Body: The primary material from which the object is constructed.
Port Use Definition
The distribution ports relating to the IfcStackTerminal are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the stack terminal occurrence is defined by IfcStackTerminalType, then the port occurrences must reflect those defined at the IfcStackTerminalType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcStackTerminal PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
"
3720;IfcWasteTerminal;"A waste terminal has the purpose of collecting or intercepting waste from one or more sanitary terminals or other fluid waste generating equipment and discharging it into a single waste/drainage system.
A waste terminal provides for all forms of trap and waste point that collects discharge from a sanitary terminal and discharges it into a waste/drainage subsystem or that collects waste from several terminals and passes it into a single waste/drainage subsystem. This includes the P and S traps from soil sanitary terminals, sinks, and basins as well as floor wastes and gully traps that provide collection points.
HISTORY New entity in IFC2x4
Type Use Definition
IfcWasteTerminal defines the occurrence of any waste terminal; common information about waste terminal types is handled by IfcWasteTerminalType.
The IfcWasteTerminalType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcWasteTerminalType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcWasteTerminalType has ports or aggregated elements, such objects are reflected at the IfcWasteTerminal occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcWasteTerminalType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcWasteTerminalType.HasPropertySets.
If both are given, then the properties directly defined at IfcWasteTerminal override the properties defined at IfcWasteTerminalType.
Refer to the documentation at the supertype IfcFlowTerminal and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcWasteTerminal is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcWasteTerminalType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Body: The primary material from which the object is constructed.
- Cover: Material from which the cover or grating is constructed.
Port Use Definition
The distribution ports relating to the IfcWasteTerminal are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the waste terminal occurrence is defined by IfcWasteTerminalType, then the port occurrences must reflect those defined at the IfcWasteTerminalType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcWasteTerminal PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
"
3724;IfcInterceptorType;"
The flow treatment device type IfcInterceptorType defines commonly shared information for occurrences of interceptors. The set of shared information may include:
- common properties with shared property sets
- common representations of shape
- common materials
- common composition of elements
- common ports
- applicable assignment of process types
It is used to define a interceptor specification (i.e. the specific product information, that is common to all occurrences of that product type). Interceptor types may be exchanged without being already assigned to occurrences.
Occurrences of IfcInterceptorType are represented by instances of IfcInterceptor.
HISTORY: New entity in IFC2x4
Property Set Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the HasPropertySets attribute. Refer to the documentation at the supertype IfcFlowTreatmentDeviceType and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
The following property set definitions are applicable to this entity according to the PredefinedType attribute:
Material Use Definition
The material of the IfcInterceptorType is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- 'Body': The primary material from which the object is constructed.
- 'Cover': Material from which the cover or grating is constructed.
- 'Strainer': Material from which the strainer is constructed.
Port Use Definition
The distribution ports relating to the IfcInterceptorType type are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship. Ports are reflected at occurrences of this type using the IfcRelDefinesByObject relationship. Refer to the documentation at IfcInterceptor for standard port definitions.
"
3734;IfcInterceptor;"An interceptor is a device designed and installed in order to separate and retain deleterious, hazardous or undesirable matter while permitting normal sewage or liquids to discharge into a collection system by gravity.
HISTORY New entity in IFC2x4
Type Use Definition
IfcInterceptor defines the occurrence of any interceptor; common information about interceptor types is handled by IfcInterceptorType.
The IfcInterceptorType (if present) may establish the common type name, usage (predefined type), properties, materials, ports, composition, assignments, and representations.
The IfcInterceptorType is attached using the IfcRelDefinesByType objectified relationship and is accessible by the IsTypedBy inverse attribute.
If the IfcInterceptorType has ports or aggregated elements, such objects are reflected at the IfcInterceptor occurrence using the IfcRelDefinesByObject relationship.
Property Use Definition
The property sets relating to this entity are defined by IfcPropertySet and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
Property sets may also be specified at the IfcInterceptorType, defining the common property data for all occurrences of the same type.
They are then accessible by the IsTypedBy inverse attribute pointing to IfcInterceptorType.HasPropertySets.
If both are given, then the properties directly defined at IfcInterceptor override the properties defined at IfcInterceptorType.
Refer to the documentation at the supertype IfcFlowTreatmentDevice and ancestors for inherited property set definitions.
The following property set definitions are applicable to this entity:
Quantity Use Definition
The quantities relating to this entity are defined by IfcElementQuantity and attached by the IfcRelDefinesByProperties relationship.
They are accessible by the IsDefinedBy inverse attribute.
The following base quantities are defined and shall be exchanged with the IfcElementQuantity.Name = 'BaseQuantities'.
Other quantities, being subjected to local standard of measurement, may be defined with another string value assigned to Name.
In this case a valid value for MethodOfMeasurement shall be provided.
Material Use Definition
The material of the IfcInterceptor is defined by IfcMaterialConstituentSet or as a fallback by IfcMaterial, and attached by the RelatingMaterial attribute on the IfcRelAssociatesMaterial relationship. It is accessible by the HasAssociations inverse attribute. Material information can also be given at the IfcInterceptorType, defining the common attribute data for all occurrences of the same type. The following keywords for IfcMaterialConstituentSet.MaterialConstituents[n].Name shall be used:
- Body: The primary material from which the object is constructed.
- Cover: Material from which the cover or grating is constructed.
- Strainer: Material from which the strainer is constructed.
Port Use Definition
The distribution ports relating to the IfcInterceptor are defined by IfcDistributionPort and attached by the IfcRelConnectsPortToElement relationship.
If the interceptor occurrence is defined by IfcInterceptorType, then the port occurrences must reflect those defined at the IfcInterceptorType using the IfcRelDefinesByObject relationship.
Ports are specific to the IfcInterceptor PredefinedType as follows indicated by the IfcDistributionPort Name, PredefinedType, and FlowDirection:
"
3742;IfcClassification;"
An IfcClassification is used for the arrangement of objects into a class or category according to a common purpose or their possession of common
characteristics. A classification in the sense of IfcClassification is taxonomy, or taxonomic scheme, arranged in a hierarchical structure. A category of objects relates to other categories in a generalization-specialization relationship. Therefore the classification items in an
classification are organized in a tree structure.
HISTORY New class in IFC Release 1.5. Modified in IFC 2x.
IFC 2x4 CHANGE Attribute Edition made optional. Attributes: PublicationLocation, Description and ReferenceTokens added. Inverse attribute HasClassificationReferences added.
Classification use definitions
IfcClassification identifies the classification system or source from which a classification notation is derived. Each classification reference or classification item, belonging to a single classification system, shall reference a single instance of IfcClassification. Therefore, each particular classification system or source used should have only one IfcClassification instance. However, because multiple classification is allowed, there may be many IfcClassification objects used, each identifying a different classification system or source.
A classification system declared may be either formally published (such as Omniclass, Uniclass, Masterformat, or DIN) or it may be a locally defined method of classifiying information. There are two methods to define a classification system within an IFC dataset:
- Including the classification system structure within the dataset: Here a hierarchical tree of IfcClassificationItem's is included that defines the classification system including the relationship between the classification items. An IfcClassificationNotation is used to classify an object.
- Referencing the classification system by a classification key or id: Here the IfcClassificationReference is used to assign a classification id or key to each classified object.
"
3752;IfcExternalInformation;"
An IfcExternalInformation is the identification of an information source that is not explicitly represented in the current model or in the project database (as an implementation of the current model). The IfcExternalInformation identifies the external source (classification, document, or library), but not the particular items such as a dictionary entry, a classification notation, or a document reference within the external source
The IfcExternalInformation is an abstract supertype of
all external information entities.
HISTORY New entity in IFC2x4.
"
3756;IfcLibraryInformation;"
An IfcLibraryInformation describes a library where a library is a structured store of information, normally organized in a manner which allows information lookup through an index or reference value. IfcLibraryInformation provides the library Name and optional Version, VersionDate and Publisher attributes. A Location may be added for electronic access to the library.
NOTE The complete definition of the information in an external library is out of scope in this IFC release.
HISTORY New
Entity in IFC2x.
IFC2x4 CHANGE Location attribute added, HasLibraryReferences inverse attribute added (previous LibraryReference changed to inverse).
"
3765;IfcLibraryReference;"
An IfcLibraryReference is a reference into a library of information by Location (provided as a URI). It also provides an optional inherited Identification key to allow more specific references to library sections or tables. The inherited Name attribute allows for a human interpretable identification of the library item. Also, general information on the library from which the reference is taken, is given by the ReferencedLibrary relation which identifies the relevant occurrence of IfcLibraryInformation.
The ifcLibraryReference additionally provides the capability to handle multilingual library entries. The Language attribute then holds the language tag for the language used by the strings kept in the Name and the Description attribute.
HISTORY New Entity in IFC2.0.
IFC2x4 CHANGE Description and Language attribute added; ReferencedLibrary attribute added (reversing previous ReferenceIntoLibrary inverse relationship).
"
3770;IfcExternalReference;"
An IfcExternalReference is the identification of information that is not explicitly represented in the current model or in the project database (as an implementation of the current model). Such information may be contained in classifications, documents or libraries. The IfcExternalReference identifies a particular item, such as a
dictionary entry, a classification notation, or a document reference within the external source.
Only the Location (as a URL) is given to describe the place where the information can be found. Also an optional
Identification as a key to allow more specific references (as to sections or tables) is provided. The Identification defines a system interpretable method to identify the relevant part of information at the source. In addition a human interpretable Name can be assigned to identify the information subject, such as a classification code.
IfcExternalReference is an abstract supertype of all external reference entities.
HISTORY New entity in IFC2x.
"
3779;IfcClassificationReference;"
An IfcClassificationReference is a reference into a classification system or source (see IfcClassification) for a specific classification key (or notation).
The inherited attributes have the following meaning:
- Identification: holds the key provided for a specific references to classification items (or tables).
- Name: allows for a human interpretable designation of a classification notation.
- Location: optionally holds a direct URI link into the classification system (or source) to hyperlink the classification key.
The IfcClassificationReference can either be assigned directly to the IfcClassification, such as if no classification hierarchy has to be included, or it references the parent classification notation, if the fully classification hierarchy is included in the data set. The attribute ReferencedSource then holds the following information (choice by IfcClassificationReferenceSelect):
- being of type IfcClassification: direct reference to the classification system (with meta information provided), used for highest level of classification notations, or if the classification notation hierarchy is not relevant,
- being of type IfcClassificationReference: reference to the parent classification notation within the classification hierarchy.
HISTORY New entity in IFC 2x.
IFC2x4 CHANGE The attribute Description and inverse attribute HasReferences are added. The attribute Identification has been renamed from ItemReference.
Use definitions
The IfcClassificationReference can be used to only assign classification keys to objects, or to hold a fully classification hierarchy. The first is refered to as ""lightweight classification"", and the second as ""full classification""
The IfcClassificationReference can be used as a form of 'lightweight' classification through the 'Identification' attribute inherited from the abstract IfcExternalReference class. In this case, the 'Identification' could take (for instance) the Uniclass notation ""L6814"" which, if the classification was well understood by all parties and was known to be taken from a particular classification source, would be sufficient. The Name attribute could be the title ""Tanking"". This would remove the need for the overhead of the more complete classification structure of the model.
"
3787;IfcDocumentReference;"
An IfcDocumentReference is a reference
to the location of a document. The reference is given by a system
interpretable Location attribute (a URL string) where the document can be found, and an optional inherited
internal reference Identification, which refers to a system
interpretable position within the document. The optional inherited
Name attribute is meant to have meaning for human readers. Optional
document metadata can also be captured through reference to
IfcDocumentInformation.
HISTORY: New Entity in IFC Release 2.0.
Modified in IFC 2x.
"
3792;IfcDocumentInformation;"
IfcDocumentInformation captures ""metadata"" of an external document. The actual content of the document is not defined in IFC; instead, it can be found following the reference given to IfcDocumentReference.
HISTORY: New entity in IFC 2x.
"
3814;IfcDocumentElectronicFormat;"
IfcDocumentElectronicFormat captures the type of document being referenced as an external source, and for which metadata is specified by IfcDocumentInformation.
HISTORY: New entity in IFC 2x
"
3832;IfcDocumentInformationRelationship;"
An IfcDocumentInformationRelationship is a relationship class that enables a document to have the ability to reference other documents.
HISTORY New entity in Release IFC2x.
IFC2x4 CHANGE Subtyped from IfcResourceLevelRelationship, order of attributes changed.
Use definitions
This class can be used to describe relationships in which one document may reference one or more other sub documents or where a document is used as a replacement for another document (but where both the original and the replacing document need to be retained).
"
3836;IfcResourceLevelRelationship;"
IfcResourceLevelRelationship is an abstract base class for relationships between resource-level entities.
HISTORY New Entity in IFC 2x4
"
3849;IfcExternalReferenceRelationship;"
IfcExternalReferenceRelationship is a relationship entity that enables objects from the
IfcResourceObjectSelect to have the ability to be tagged by external references.
NOTE This relationship is used to assign classification, library or document information to entities that
do not inherit from IfcRoot. It has a similar functionality as the subtypes of IfcRelAssociates.
HISTORY New Entity in IFC 2x4
"
3877;IfcConstraint;"
An IfcConstraint is used to define a constraint or limiting value or boundary condition that may be applied to an object or to the value of a property.
HISTORY: New Entity in IFC Release 2.0
Use Definition
IfcConstraint may be associated with any subtype of IfcRoot (unless restricted in specific subtypes) through the IfcRelAssociatesConstraint relationship in the IfcControlExtension schema, or may be associated with IfcProperty by IfcPropertyConstraintRelationship.
A constraint may aggregate other constraints through the IfcConstraintAggregationRelationship through which a logical association between constraints may be applied, or constraints may have other defined relationship to other constraints via IfcConstraintRelationship.
A constraint must have a name applied through the IfcConstraint.Name attribute and optionally, a description through IfcConstraint.Description. The grade of the constraint (hard, soft, advisory) must be specified through IfcConstraint.ConstraintGrade or IfcConstraint.UserDefinedGrade whilst the source, creating actor and time at which the constraint is created may be optionally asserted through IfcConstraint.ConstraintSource, IfcConstraint.CreatingActor and IfcConstraint.CreationTime.
A constraint may also have additional external information (such as classification or document information) associated to it by IfcExternalReferenceRelationship, accessible through inverse attribute IfcConstraint.HasExternalReferences
"
3893;IfcObjective;"
An IfcObjective captures qualitative information for an objective-based constraint.
HISTORY: New Entity in IFC Release 2.0
Use definition
IfcObjective is a subtype of IfcConstraint and may be associated with any subtype of IfcRoot through the IfcRelAssociatesConstraint relationship in the IfcControlExtension schema, or may be associated with IfcProperty by IfcPropertyConstraintRelationship.
The aim of IfcObjective is to specify the purpose for which the constraint is applied and to capture the values of the constraint. These may be both the benchmark values that are intended to indicate the constraint extent and the resulting values in use that enable performance comparisons to be applied.
"
3899;IfcMetric;"
An IfcMetric is used to capture quantitative resultant metrics that can be applied to objectives.
HISTORY: New Entity in IFC Release 2.0
Use Definition
IfcMetric is a subtype of IfcConstraint and may be associated with any subtype of IfcRoot through the IfcRelAssociatesConstraint relationship in the IfcControlExtension schema, or may be associated with IfcProperty by IfcPropertyConstraintRelationship.
The aim of IfcMetric is to capture the quantitative aspects of a constraint.
For instance, when undertaking a move (instantiated through the IfcTask class), a constraint is instantiated as the class IfcMetric and may be named as a 'Move Start Constraint' or 'Move End Constraint' and described using one of a possible range of move constraints as shown in the table below.
| Constraint |
Description |
Benchmark |
Grade |
| ASSOONASPOSSIBLE |
Action should commence at the earliest possible opportunity. |
GREATERTHANOREQUALTO |
SOFT |
| MUSTSTARTON |
Action must start at a prescribed date/time. |
EQUALTO |
HARD |
| MUSTSTARTBEFORE |
Action must start before a prescribed date/time. |
LESSTHANOREQUALTO |
HARD |
| MUSTSTARTAFTER |
Action must not start before a prescribed date/time. |
GREATERTHANOREQUALTO |
HARD |
| MAYSTARTAFTER |
Action may start at any time following a prescribed date/time. |
GREATERTHANOREQUALTO |
SOFT |
| MUSTFINISHON |
Action must be complete at or by a prescribed date/time. |
EQUALTO |
HARD |
| MUSTFINISHBEFORE |
Action must be complete before a prescribed date/time. |
LESSTHANOREQUALTO |
HARD |
This constraint (instantiated as IfcMetric) uses a Date/Time value in IfcMetric.DataValue through IfcMetricValueSelect. An appropriate benchmark is applied according to the requirement of the constraint (as indicated) by IfcMetric.Benchmark. The grade of the constraint (hard, soft, advisory) must be specified through IfcConstraint.ConstraintGrade whilst the time at which the constraint is created may be optionally asserted through IfcConstraint.CreationTime.
"
3937;IfcResourceConstraintRelationship;"
An IfcResourceConstraintRelationship is a relationship
entity that enables a constraint to be related to one or more
resource level objects.
HISTORY New Entity in Release IFC2x2.
IFC2x4 CHANGE Renamed from IfcPropertyConstraintRelationship and extended to apply to all resource level entities. Subtyped from IfcResourceLevelRelationship.
Use definition
An IfcResourceConstraintRelationship allows for the
specification of a constraint to be applied to many entity types.
An important case is to apply constraints to properties. The
constraints applied therefore enable a property to carry values
identifying requirements as well as those identifying the
fulfilment of those requirements.
Figure 238 shows how a constraint may be applied to a property within a property set. For simplicity, only the mandatory attributes are shown as asserted. It shows how a property 'ThingWeight' which has a nominal value of 19.5 kg has two constraints that are logically aggregated by an AND connection. One of the constraints has a benchmark of 'GREATERTHANOREQUALTO' whilst the second has a benchmark of 'LESSTHANOREQUALTO'. This means that the constraint must lie between these two bounding values. The relating constraint is instantiated as an objective named as 'Weight Constraint' and qualified as a SPECIFICATION constraint. The two related constraints are both specified as metrics since they can have specific values.
![]() |
Figure 238 — Resource constraint relationship |
"
3940;IfcConstraintRelationship;"
An IfcConstraintRelationship is an objectified relationship that enables instances of IfcConstraint and its
subtypes to be associated to each other. Logical aggregation of instances of IfcConstraint and its subtypes is handled by the subtype IfcConstraintAggregationRelationship.
EXAMPLE: Certain constraints related to an IfcWall may be derived from a constraint related to an
IfcSpace.
HISTORY New entity in Release IFC2x2 (Addendum 1).
IFC2x4 CHANGE Subtyped from IfcResourceLevelRelationship.
"
3945;IfcConstraintAggregationRelationship;"
An IfcConstraintAggregationRelationship is an objectified relationship that enables instances of IfcConstraint subtypes to be aggregated together logically.
HISTORY New Entity in IFC Release 2.0. Modified in IFC2x2.
IFC2x4 CHANGE Subtyped from IfcConstraintRelationship
Use definition
IfcConstraintAggregationRelationship allows the aggregation link between subtypes of constraint to be logically defined (AND, OR, XOR, NOTAND, NOTOR). In this way, whereby an object or property can have multiple constraints assigned, and the logical linkage between them can be specified. Thus linked constraints might show as for example (> X AND < Y) which is useful for an allowed range, or bounded value, for example, (A OR B OR C) which is valuable for an enumerated property where a selection is constrained to be (at least) one of A, B or C.
Figure 237 illustrates constraint aggregation.
![]() |
Figure 237 — Constraint aggregation |
"
3954;IfcCostValue;"
IfcCostValue is an amount of money or a value that affects an amount of money.
HISTORY: New Entity in IFC Release 1.0
Use definitions
Each instance of IfcCostValue may also have a CostType. There are many possible types of cost value that may be identified. While there is a broad understanding of the meaning of names that may be assigned to different types of costs, there is no general standard for naming cost types nor are there any broadly defined classifications. To allow for any type of cost value, the IfcLabel datatype is assigned.
The following defines some cost types that might be applied:
- Annual rate of return
- Bonus
- Bulk purchase rebate
- Contract
- Consultancy
- Delivery
- Estimated cost
- Hire
- Installation
- Interest rate
- Labor
- Lease
- List price
- Maintenance
- Material
- Overhead
- Postage and packing
- Profit
- Purchase
- Rental
- Repair
- Replacement
- Sale
- Small quantity surcharge
- Spares
- Storage
- Sub-Contract
- Trade discount
- Transportation
- Waste allowance
- Whole life
In the absence of any well-defined standard, it is recommended that local agreements should be made to define allowable and understandable cost value types within a project or region.
"
3957;IfcAppliedValue;"
IfcAppliedValue is an abstract supertype that specifies the common attributes for cost values.
HISTORY: New Entity in IFC2x2. Modifed in IFC2x4 to use IfcDate for date values.
Use definitions
The extent of the IfcAppliedValue is determined by the AppliedValue attribute which may be defined either as an IfcMeasureWithUnit or as an IfcMonetaryMeasure or as an IfcRatioMeasure via the IfcAppliedValueSelect type.
Optionally, an IfcAppliedValue may have an applicable date. This is intended to fix the date on which the value became relevant for use. It may be the date on which the value was set in the model or it may be a prior or future date when the value becomes operable.
Similarly, an IfcAppliedValue may have a 'fixed until' date. This is intended to fix the date on which the value ceases to be relevant for use.
An instance of IfcAppliedValue may have a unit basis asserted. This is defined as an IfcMeasureWithUnit that determines the extent of the unit value for application purposes. It is assumed that when this attribute is asserted, then the value given to IfcAppliedValue is that for unit quantity. This is not enforced within the IFC schema and thus needs to be controlled within an application.
Applied values may be referenced from a document (such as a price list). The relationship between one or more occurrences of IfcAppliedValue (or its subtypes) is achieved through the use of the IfcExternalReferenceRelationship in which the document provides the IfcExternalReferenceRelationship.RelatingExtReference and the value occurrences are the IfcExternalReferenceRelationship.RelatedResourceObjects.
"
3973;IfcCurrencyRelationship;"
IfcCurrencyRelationship defines the rate of exchange
that applies between two designated currencies at a particular time
and as published by a particular source.
HISTORY New Entity in IFC2x2.
IFC2x4 CHANGE Subtyped from IfcResourceLevelRelationship, attribute order changed.
Use definitions
An IfcCurrencyRelationship is used where there may be a need to reference an IfcCostValue in one currency to an IfcCostValue in another currency. It takes account of fact that currency exchange rates may vary by requiring the recording the date and time of the currency exchange rate used and the source that publishes the rate. There may be many sources and there are different strategies for currency conversion (spot rate, forward buying of currency at a fixed rate).
The source for the currency exchange is defined as an instance of IfcLibraryInformation that includes a name and a URL.
"
3979;IfcAppliedValueRelationship;"
An IfcAppliedValueRelationship is a relationship class that enables cost values to be aggregated together as components of another cost value.
HISTORY New Entity in Release IFC2.0.
IFC2x4 CHANGE Subtyped from IfcResourceLevelRelationship, attribute order changed.
Use definitions
Dependency relationships can exist between applied values on the basis that one particular value may be determined by operations on one or more other values. This is captured through the IfcAppliedValueRelationship entity. In this relationship, one instance of IfcAppliedValue acts as the principal (IfcAppliedValueRelationship.ComponentOf) whose value may be
determined from the instances of IfcAppliedValue that are defined as its components
(IfcAppliedValueRelationship.Components)
An IfcAppliedValueRelationship has an ArithmeticOperator attribute that specifies the form of arithmetical operation implied by the relationship.
A practical consideration when using the applied value relationship is that when the arithmetic operator is ADD, then the
type of the IfcAppliedValue.AppliedValue attribute will be IfcMeasureWithUnit or IfcMonetaryMeasure while if the arithmetic operator is MULTIPLY, then the type of the IfcAppliedValue.AppliedValue attribute for one instance of
IfcAppliedValue will be IfcMeasureWithUnit or IfcMonetaryMeasure while for other instances it will be
IfcRatioMeasure.
If the arithmetic operator is SUBTRACT or DIVIDE then there can only be two occurrences of IfcAppliedValue that can contribute and the order in which they occur is significant. The value of (A - B) will usually differ from the value of (B - A) whilst (X / Y) is the reciprocal of (Y / X).
Figure 239 illustrates one level aggregation of applied values. A relationship exists between applied value A and applied values B, C and D such that the value of A is determined by the addition of B, C and D such that: A = B + C + D
![]() |
Figure 239 — Applied value relationship single level |
Figure 240 illustrates two level aggregation of applied values. It is possible to develop more complex applied value specifications by creating hierarchies of applied value relationships. In the diagram, the development of a applied value is shown whereby, because B = E * F and D = G * H * J, then: A = ((E * F) + C + (G * H * J)).
![]() |
Figure 240 — Applied value relationship multiple level |
"
3989;IfcResourceCost;"
IfcResourceCost defines cost information for resources.
HISTORY: New Entity in IFC 2x4.
"
4005;IfcTimeSeries;"
A time series is a set of a time-stamped data entries. It allows a natural association of data collected over intervals of time. Time series can be regular or irregular. In regular time series data arrive predictably at predefined intervals. In irregular time series some or all time stamps do not follow a repetitive pattern and unpredictable bursts of data may arrive at unspecified points in time.
The modeling of buildings and their performance involves data that are generated and recorded over a period of time. Such data cover a large spectrum, from weather data to schedules of all kinds to status measurements to reporting to everything else that has a time related aspect. Their correct placement in time is essential for their proper understanding and use, and the IfcTimeSeries subtypes provide the appropriate data structures to accommodate these types of data.
HISTORY: New entity in IFC 2x2.
"
4017;IfcRegularTimeSeries;"
In a regular time series, the data arrives predictably at predefined intervals. In a regular time series there is no need to store multiple time stamps and the algorithms for analyzing the time series are therefore significantly simpler. Using the start time provided in the supertype, the time step is used to identify the frequency of the occurrences of the list of values.
EXAMPLE: A smoke detector samples the concentration of particulates in a space at a fixed rate (for example, every six seconds); a control system measures the outside air temperature every hour.
HISTORY: New entity in IFC 2x2.
"
4020;IfcTimeSeriesValue;"
A time series value is a list of values that comprise the time series. At least one value must be supplied. Applications are expected to normalize values by applying the following three rules:
- All time (universal, local, daylight savings, and solar) is normalized against the ISO 8601 standard GMT/UTC (Universal Coordinated Time).
- Any rollover is handled by the application providing the data. Rollover occurs, for example, when the measurement device resets itself while measuring and the recording data do not include the data measured before the reset.
- The normalized data refer to the preceding time unit. The time series example shown in Figure 241 below contains four time points: Time ""a"" indicates the beginning of the time series and the associated datum has no relevance. Data at time points ""b,"" ""c"" and ""d"" are associated with values 1, 2 and 3, respectively.
![]() |
Figure 241 — Time series value |
HISTORY New entity in IFC2x2.
"
4022;IfcIrregularTimeSeries;"
In an irregular time series, unpredictable bursts of data arrive at unspecified points in time, or most time stamps cannot be characterized by a repeating pattern.
EXAMPLE: A circulating pump cycles on and off at unpredictable times as dictated by the demands on the piping system; the amount of light in a classroom varies depending on when the lights are manually switched on and off and and how many lamps are controlled by each switch.
HISTORY: New entity in IFC 2x2.
"
4024;IfcIrregularTimeSeriesValue;"
The IfcIrregularTimeSeriesValue describes a value (or set of values) at a particular time point.
HISTORY: New entity in IFC 2x2.
"
4041;IfcTaskTime;"
IfcTaskTime captures the time-related information about a task including the different types (actual or scheduled) of starting and ending times.
HISTORY: New entity in IFC2x4, adapted from IfcScheduleTimeControl. Differently to IfcScheduleTimeControl it is also possible to differentiate duration time measures between the two possible types; (1) work time and (2) elapsed time.
Use definitions
All given values should be provided by the application; the IFC schema does not deal with dependencies between task time values. There is also no consistency check through where rules that guarantee a meaningful population of time values. Thus, an application is responsible to provide reasonable values and, if an application receives task times, has to make consistency checks by their own.
IfcTaskTime furthermore provides a generic mechanism to differentiate between user given time values and time values derived from user given time values and other constraints such as work calendars and assigned resources.
"
4060;IfcSchedulingTime;"
IfcSchedulingTime is the abstract supertype of entities that capture time-related information of processes.
HISTORY: New entity in IFC2x4.
"
4069;IfcLagTime;"
IfcLagTime describes the time parameters that may exist within a sequence relationship between two processes.
HISTORY: New entity in IFC Release 2x4.
Use Definitions
An IfcLagTime provides information about the
time lag that exists between the predecessor and successor
process in a sequence. The assertion of the time lag is
optional for a sequence but for work schedules that
specifically deal with processes occurring at particular
times, it should be asserted.
A lag time has a duration type. This allows the
identification of whether elapsed time or work time is
being measured (where work time is the estimate of the time
required to complete the process and elapsed time being the
amount of time actually allocated to the process)
The form of measurement of the duration can be captured.
Allowed values for this are MEASURED, PREDICTED or
SIMULATED. The selection of this value depends on the use
of the schedule. A NOTDEFINED value is also allowed.
The value of the time lag may be selected as being either a
percentage ratio or an actual time measure. If selected as
a ratio, the percentage should apply to the duration of the
predecessor process (relating process) such that e.g. a
value of 0.5 (50%) would indicate that the successor task
should start when the predecessor task is 50% complete (if
a START-START sequence type is used) or should wait for 50%
of the duration of the predecessor process to have elapsed
after the finish of the predecessor process in case of a
FINISH-START sequence type.
The time unit for the task duration may also be set and
this may be set to any allowed unit of time measure.
"
4079;IfcResourceTime;"
IfcResourceTime captures the time-related information about a construction resource.
HISTORY: New entity in IFC2x4.
"
4095;IfcEventTime;"
IfcEventTime captures the time-related information about an event
including the different types of event dates (i.e. actual,
scheduled, early, and late).
HISTORY: New entity in IFC2x4.
Use definitions
All given values should be provided by the application,
i.e. the IFC schema does not deal with dependencies between
process time values. At this stage there is also no
consistency check through where rules that guarantee a
meaningful population of date values. Thus, an application
is responsible to provide reasonable values and, if an
application receives event dates, has to make consistency
checks by their own.
IfcEventTime furthermore provides a generic
mechanism to differentiate between user given time values
and time values derived from user given time values and
other constraints such as work calendars and assigned
resources (derived from the process graph). The data origin flag
is provided as a single attribute applying to all date time related attributes
of IfcEventTime.
"
4100;IfcWorkTime;"
IfcWorkTime defines time periods that are used by IfcWorkCalendar for either describing working times or non-working exception times. Besides start and finish dates, a set of time periods can be given by various types of recurrence patterns.
HISTORY: New entity in IFC2x4.
Use definitions
A work time should have a meaningful name that describes the time periods (for example, working week, holiday name). Non-recurring time periods should have a start date (IfcWorkTime.Start) and a finish date (IfcWorkTime.Finish). In that case it is assumed that the time period begins at 0:00 on the start date and ends at 24:00 on the finish date.
The start and finish date is optional if a recurrence pattern is given (IfcWorkTime.RecurrencePattern). They then restrict never-ending recurrence patterns.
"
4104;IfcRecurrencePattern;"
IfcRecurrencePattern defines repetitive time periods on the basis of regular recurrences such as each Monday in a week, or every third Tuesday in a month. The population of the remaining attributes such as DayComponent, Position, and Interval depend on the specified recurrence type.
HISTORY: New entity in IFC2x4.
Use definitions
IfcRecurrencePattern supports various recurrence patterns that are differentiated by a type definition (IfcRecurrencePattern.RecurrenceType), which is required to provide the meaning of the given values. It can be further constrained by applicable times through specified IfcTimePeriod instances, thus enabling time periods such as between 7:00 and 12:00 and between 13:00 and 17:00 for each of the applicable days, weeks or months.
"
4128;IfcTimePeriod;"
IfcTimePeriod defines a time period given by a start and end time. Both time definitions consider the time zone and allow for the daylight savings offset.
HISTORY: New entity in IFC R2x4.
Use definitions
A time period is defined by a start and an end time, which is defined by IfcTime. The given time period should be within reasonable values (for example, the start time must be before the end time). It is furthermore expected that both time definitions use the same time zone and, if given, the same daylight saving offset.
"
4131;IfcTaskTimeRecurring;"
IfcTaskTimeRecurring is a recurring instance of IfcTaskTime for handling regularly scheduled or repetitive tasks.
HISTORY: New entity in IFC2x4.
"
4134;IfcConnectionGeometry;"
IfcConnectionGeometry is used to describe the geometric and topological constraints that facilitate the physical connection of two objects. It is envisioned as a control that applies to the element connection relationships.
NOTE The element connection relationship normally provides for a logical connection information, by referencing the relating and related elements. If in addition an IfcConnectionGeometry is provided, physical connection information is given by specifying exactly where at the relating and related element the element connection occurs.
Using the eccentricity subtypes, the connection can also be described when there is a physical distance (or eccentricity) between the connection elements.
The IfcConnectionGeometry allows for the provision of connection constraints between geometric and topological elements, the following connection geometry/topology types are in scope:
- point | vertex point,
- curve | edge curve,
- surface | face surface,
HISTORY New entity in IFC Release 1.5.
IFC2x Edition 3 CHANGE The definition of the subtypes has been enhanced by allowing either geometric representation items (point | curve | surface) or topological representation items with associated geometry (vertex point | edge curve | face surface).
"
4139;IfcConnectionPointGeometry;"
IfcConnectionPointGeometry
is used to describe the geometric constraints that facilitate the
physical connection of two objects at a point (here IfcCartesianPoint) or at an vertex with point
coordinates associated. It is envisioned as a control that applies to the element connection relationships.
EXAMPLE The connection relationship between two path based elements (like a column and a beam) has a geometric constraint which describes the connection points by a PointOnRelatingElement for the column and a PointOnRelatedElement for the beam. The exact usage of the IfcConnectionPointGeometry is further defined in the geometry use sections of the elements that use it.
NOTE If the point connection has an offset (if the two points or vertex points at the relating and related element do not physically match), the subtype IfcConnectionPointEccentricity shall be used.
HISTORY New entity in IFC Release 1.5, has been renamed from IfcPointConnectionGeometry in IFC Release 2x.
IFC2x Edition 3 CHANGE The provision of topology with associated geometry, IfcVertexPoint, is
enabled by using the IfcPointOrVertexPoint.
Geometry use definitions
The IfcPoint (or the IfcVertexPoint with an associated IfcPoint) at the PointOnRelatingElement attribute defines the point where the basic geometry items of the connected elements connect. The point coordinates are provided within the local coordinate system of the RelatingElement, as specified at the IfcRelConnectsSubtype that utilizes the IfcConnectionPointGeometry. Optionally, the same point coordinates can also be provided within the local coordinate system of the RelatedElement by using the PointOnRelatedElement attribute. If both point coordinates are not identical within a common parent coordinate system (ultimately within the world coordinate system), the subtype IfcConnectionPointEccentricity shall be used.
"
4143;IfcConnectionPointEccentricity;"
IfcConnectionPointEccentricity is used to describe the geometric constraints that facilitate the physical connection of two objects at a point or vertex point with associated point coordinates. There is a physical distance, or eccentricity, etween the connection points of both object. The eccentricity can be either given by:
- providing the PointOnRelatingElement and the PointOnRelatedElement, where both˙point coordinates are not identical within a common parent coordinate system (latestly within the world coordinate system),
- providing the PointOnRelatingElement and the three distance measures, EccentricityInX, EccentricityInY, and EccentricityInZ (or only EccentricityInX, and EccentricityInY if the
underlying coordinate system is two-dimensional), or
- providing both.
NOTE˙ If both, PointOnRelatedElement, and EccentricityInX, EccentricityInY, (EccentricityInZ) are provided, the values should be consistent. In case of any non-consistency, the calculated distance between PointOnRelatingElement and PointOnRelatedElement takes precedence.
The explicit values for EccentricityInX, EccentricityInY, and EccentricityInZ are always
measured in the following direction and coordinate system (defining when the value is positive or negative):
- from the PointOnRelatedElement to PointOnRelatingElement within the coordinate system of the RelatingElement.
- in addition: when used to specify connections in structural analysis models, the IfcStructuralMember is to be used as the RelatingElement of the relationship object utilizing IfcConnectionPointEccentricity, and the IfcStructuralConnection is the RelatedElement.
HISTORY˙ New entity in IFC 2x Edition 3.
Geometry use definitions
The IfcPoint (or the IfcVertexPoint with an associated IfcPoint) at the PointOnRelatingElement attribute defines the point where the basic geometry items of the connected elements connects. The point coordinates are provided within the local coordinate system of the RelatingElement, as specified at the IfcRelConnects subtype that utilizes the IfcConnectionPointGeometry. Optionally, the same point coordinates can also be provided within the local coordinate system of the RelatedElement by using the PointOnRelatedElement attribute, otherwise the distance to the point at the RelatedElement has to be given by the three eccentricity values.
"
4150;IfcConnectionCurveGeometry;"
IfcConnectionCurveGeometry is used to describe the geometric constraints that facilitate the physical connection of two objects at a curve or at an edge with curve geometry associated. It is envisioned as a control that applies to the element connection relationships.
EXAMPLE The connection relationship between two walls has a geometric constraint which describes the end caps (or cut-off of the wall ends) by a CurveOnRelatingElement for the first wall and a CurveOnRelatedElement for the second wall. The exact usage of the IfcConnectionCurveGeometry is further defined in the geometry use sections of the elements that use it.
The available geometry for the connection constraint may be further restricted to only allow straight segments by applying IfcPolyline
only. Such an usage constraint is provided at the object definition of the IfcElement subtype, utilizing the element connection by referring to the subtype of IfcRelConnects with the associated IfcConnectionCurveGeometry.
HISTORY New entity in IFC Release 1.5, has been renamed from IfcLineConnectionGeometry in IFC Release 2x.
IFC2x Edition 3 CHANGE The provision of topology with associated geometry, IfcEdgeCurve, is enabled by using the IfcCurveOrEdgeCurve.
Geometry use definitions
The IfcCurve (or the IfcEdgeCurve with an associated IfcCurve) at the CurveOnRelatingElement attribute defines the curve where the basic geometry items of the connected elements connects. The curve geometry and coordinates are provided within the local coordinate system of the RelatingElement, as specified at the IfcRelConnects Subtype that utilizes the IfcConnectionCurveGeometry. Optionally, the same curve geometry and coordinates can also be provided within the local coordinate system of the RelatedElement by using the CurveOnRelatedElement attribute.
"
4156;IfcConnectionSurfaceGeometry;"
IfcConnectionSurfaceGeometry is used to describe the geometric constraints that facilitate the physical connection of two objects at a surface or at a face with surface geometry associated. It is envisioned as a control that applies to the element connection relationships.
HISTORY New entity in IFC Release 2x.
IFC2x Edition 3 CHANGE The provision of topology with associated geometry, IfcFaceSurface, is enabled by using the IfcSurfaceOrFaceSurface.
Geometry use definitions
The IfcSurface (or the IfcFaceSurface with an associated IfcSurface) at the SurfaceOnRelatingElement attribute defines the surface where the basic geometry items of the connected elements connects. The surface geometry and coordinates are provided within the local coordinate system of the RelatingElement, as specified at the IfcRelConnectsSubtype that utilizes the IfcConnectionSurfaceGeometry. Optionally, the same surface geometry and coordinates can also be provided within the local coordinate system of the RelatedElement by using the SurfaceOnRelatedElement attribute.
"
4163;IfcConnectionVolumeGeometry;"
IfcConnectionVolumeGeometry is used to describe the geometric constraints that facilitate the physical connection (or overlap) of two objects at a volume defined by a solid or closed shell. It is envisioned as a control that applies to the element connection or interference relationships.
HISTORY˙ New entity in IFC2x4.
Geometry use definitions
The IfcSolidModel (or the IfcClosedShell) at the VolumeOnRelatingElement attribute defines the volume where the basic geometry items of the interfering elements overlap. The volume geometry and coordinates are provided within the local coordinate system of the RelatingElement, as specified at the subtypes of the relationship IfcRelConnects that utilizes the IfcConnectionSurfaceGeometry. Optionally, the same˙volume geometry and coordinates can also be provided within the local coordinate system of the RelatedElement by using the VolumeOnRelatedElement attribute.
"
4169;IfcGridAxis;"
An individual axis, IfcGridAxis, is defined in the context of a design grid. The axis definition is based on a curve of dimensionality 2. The grid axis is positioned within the XY plane of the position coordinate system defined by the IfcDesignGrid.
HISTORY New entity in IFC Release 1.0
Geometry use definitions
The standard geometric representation of IfcGridAxis is
defined using a 2D curve entity. Grid axes are normally defined
by an offset to another axis. The IfcOffsetCurve2D
supports this concept.
Each grid axis has a sense given by the parameterization of
the curve. The attribute SameSense is an indicator of
whether or not the sense of the grid axis agrees with, or
opposes, that of the underlying curve.
As shown in Figure 242, the grid axis is defined as a 2D curve within
the xy plane of the position coordinate system. Any curve can be
used to define a grid axis, most common is the use of IfcLine for
linear grids and IfcCircle for radial grids.
Most grids are defined by a pair of axis
lists, each defined by a base grid axis and axes given by an
offset to the base axis. The use of IfcOffsetCurve2D as
underlying AxisCurve supports this concept.
![]() |
Figure 242 — Grid axis |
"
4179;IfcVirtualGridIntersection;"
IfcVirtualGridIntersection defines the derived location of the intersection between two grid axes. Offset values may be given to set an offset distance to the grid axis for the calculation of the virtual grid intersection.
The two intersecting axes (IntersectingAxes) define the intersection point, which exact location (in terms of the Cartesian point representing the intersection) has to be calculated from the geometric representation of the two participating curves.
NOTE The IfcGrid local placement, that can be provided relative to the local placement of another spatial structure element, has to be taken into account for calculating the absolute placement of the IfcVirtualGridIntersection. Where rules and informal rules ensure, that the IntersectingAxes belong to the same IfcGrid
Offset values may be given (OffsetDistances). If given, the position within the list of OffsetDistances
corresponds with the position within the list of IntersectingAxes. Therefore:
- OffsetDistances[1] sets the offset to IntersectingAxes[1],
- OffsetDistances[2] sets the offset to IntersectingAxes[2], and
- OffsetDistances[3] sets the offset to the virtual intersection in direction of the orientation of the cross product
of IntersectingAxes[1] and the orthogonal complement of the IntersectingAxes[1] (which is the positive or negative
direction of the z axis of the design grid position).
HISTORY New entity in IFC Release 1.5. The entity name was changed from IfcConstraintRelIntersection in IFC Release 2x.
Informal Propositions:
- Both, IntersectingAxes[1] and
IntersectingAxes[2] shall be two IfcGridAxis
defined by the same IfcGrid.
- IntersectingAxes[1] and IntersectingAxes[2]
shall not be part of the same row of grid axes, i.e. both shall
not be within the same set of IfcGrid.UAxes or
IfcGrid.VAxes of the corresponding IfcGrid.
Geometry use definitions:
The following figures explain the usage of the OffsetDistances and IntersectingAxes attributes.
Figure 246 illustrates two offset distances given where the virtual intersection is defined in the xy plane of the grid axis placement.
![]() |
Figure 246 — Virtual grid intersection with two offsets |
Figure 247 illustrates three offset distances given where the virtual intersection is defined by an offset (in direction of the
z-axis of the design grid placement) to the virtual intersection in the xy plane of the grid axis placement.
![]() |
Figure 247 — Virtual grid intersection with three offsets |
The distance of the offset curve (OffsetDistances[n])
is measured from the basis curve. The distance may be positive,
negative or zero. A positive value of distance defines an offset
in the direction which is normal to the curve in the sense of an
anti-clockwise rotation through 90 degrees from the tangent
vector T at the given point. (This is in the direction of
orthogonal complement(T).) This can be reverted by the
SameSense attribute at IfcGridAxis which may switch
the sense of the AxisCurve.
Illustration
Figure 248 illustrates an example of a negative offset where the figure shows the side of the offset.
- IntersectingAxes[1].AxisCurve is an
IfcTrimmedCurve with an IfcCircle as
BasisCurve and SenseAgreement = TRUE.
- IntersectingAxes[1].SameSense = TRUE.
- OffsetDistances[1] is a negative length measure
![]() |
Figure 248 — Virtual grid intersection negative offset |
"
4182;IfcGridPlacement;"
IfcGridPlacement provides a specialization of IfcObjectPlacement in which
the placement and axis direction of the object coordinate system is defined by a reference to the design grid as defined in IfcGrid.
The location of the object coordinate system is given by the attribute PlacementLocation. It is defined as an
IfcVirtualGridIntersection, that is, an intersection between two grid axes with optional offsets.
The axis direction of the x-axis of the object coordinate
system is given either:
- PlacementRefDirection = NIL: by the tangent of the first grid axis (PlacementLocation.IntersectingAxes[1]) at the virtual intersection (maybe using the offset curve, if PlacementLocation.OffsetDistances is given);
- PlacementRefDirection = IfcDirection: by the explicitly provided direction information;
- PlacementRefDirection = IfcVirtualGridIntersection: by the tangent between the virtual grid intersection of PlacementLocation and the virtual grid intersection of PlacementRefDirection. Offsets as potentially provided in the IfcVirtualGridIntersection's of PlacementLocation and PlacementRefDirection have to be taken into account.
The direction of the y-axis of the IfcGridPlacement is the orthogonal complement to the x-axis. The plane defined by the x and y axis shall be co-planar to the xy plane of the local placement of the IfcGrid.˙
The direction of the z-axis is the orientation of the cross product of the x-axis and the y-axis, i.e. the z-axis of the IfcGridPlacement shall be co-linear to the z-axis of the local placement of the IfcGrid.
NOTE The IfcGrid local placement, that can be provided relative to the local placement of another spatial structure element, has to be taken into account for calculating the absolute placement of the virtual grid intersection.
NOTE The PlacementLocation.OffsetDistances[3] and the PlacementRefDirection.OffsetDistances[3] shall either not be assigned or should have the same z offset value.
HISTORY ˙New entity in IFC Release 1.5. The entity name was changed from IfcConstrainedPlacement in IFC Release 2x.
IFC2x4 CHANGE Attribute data type of PlacementRefDirection has been changed to IfcGridPlacementDirectionSelect.
Geometry use definitions
The following examples show the usage of placement location and direction for an IfcGridPlacement.
Figure 243 illustrates the case where PlacementRefDirection is not given - the object coordinate system is defined by:
- its location: given by the virtual grid intersection of PlacementLocation
- its x-axis direction: given by the tangent of the first intersecting axis in the offset location of the virtual grid intersection
![]() |
Figure 243 — Grid placement |
Figure 244 illustrates the case where PlacementRefDirection is given as an IfcDirection- the object coordinate system is defined by:
- its location: given by the virtual grid intersection of PlacementLocation
- its x-axis direction: given by the DirectionRatios of the IfcDirection, only the ratios for x and y are taken into account,
![]() |
Figure 244 — Grid placement with direction |
Figure 245 illustrates the case where PlacementRefDirection is given as an IfcVirtualGridIntersection- the object coordinate system is defined by:
- its location: given by the virtual grid intersection of PlacementLocation
- its x-axis direction: given by the tangent of the line between the virtual grid intersection of the PlacementLocation and the virtual grid intersection of the PlacementRefDirection.
![]() |
Figure 245 — Grid placement with intersection |
"
4185;IfcObjectPlacement;"
IfcObjectPlacement is an abstract supertype for the special types defining the object coordinate system. The
IfcObjectPlacement has to be provided for each product that has a shape representation.
The object placement can be given:
- absolute: by an axis2 placement, relative to the world coordinate system,
- relative: by an axis2 placement, relative to the object placement of another product,
- by grid reference: by the virtual intersection and reference direction given by two axes of a design grid.
In any case the object placement has to unambiguously define the object coordinate system as either two-dimensional axis placement (IfcAxis2Placement2D) or three-dimensional axis placement (IfcAxis2Placement3D). The axis placement may have to be calculated.
HISTORY New entity in IFC Release 2x.
"
4190;IfcLocalPlacement;"
IfcLocalPlacement defines the relative placement of a product in relation to the
placement of another product or the absolute placement of a product within the geometric representation context of the project.
IfcLocalPlacement allows that an IfcProduct can be placed by this IfcLocalPlacement (through
the attributeObjectPlacement) within the local coordinate system of the object placement of another IfcProduct,
which is referenced by the PlacementRelTo. Rules to prevent cyclic relative placements have to be introduced on the
application level.
If the PlacementRelTo is not given, then
the IfcProduct is placed absolutely within the
world coordinate system.
HISTORY: New entity in IFC Release 1.0.
Geometry use definitions
The following conventions shall apply as default relative positions if the relative placement is used. The conventions are given for all five direct subtypes of IfcProduct, the IfcSpatialStructureElement, IfcElement, IfcAnnotation, IfcGrid, IfcPort. More detailed placement information is given at the level of subtypes of those five types mentioned.
- For the subtypes of IfcSpatialStructureElement the following conventions apply
- IfcSite shall be placed absolutely within the world coordinate system established by the geometric
representation context of the IfcProject
- IfcBuilding shall be placed relative to the local placement of IfcSite
- IfcBuildingStorey shall be placed relative to the local placement of IfcBuilding
- For IfcGrid and IfcAnnotation the convention applies that it shall be placed relative
- to the local placement of its container (IfcSite, IfcBuilding, IfcBuildingStorey)
- it should be the same container element that is referenced by the IfcRelContainedInSpatialStructure
containment relationship,
- For IfcPort the convention applies that it shall be placed relative
- to the local placement of the element it belongs to (IfcElement)
- it should be the same element that is referenced by the IfcRelConnectsPortToElement connection
relationship,
- For IfcElement the convention applies that it shall be placed relative:
- to the local placement of its container (IfcSite, IfcBuilding, IfcBuildingStorey)
- it should be the same container element that is referenced by the IfcRelContainedInSpatialStructure
containment relationship,
- to the local placement of the IfcElement to which it is tied by an element composition relationship
- for features that are located relative to the main component (such as openings), as expressed by IfcRelVoidsElement and IfcRelProjectsElement,
- for elements that fill an opening (such as doors or windows), as expressed byIfcRelFillsElement,
- for coverings that cover the element, as expressed byIfcRelCoversBldgElements,
- for sub components that are aggregated to the main component, as expressed by IIfcRelAggregates and IfcRelNests)
If the PlacementRelTo relationship is not given, then it defaults to an absolute placement within the world
coordinate system established by the referenced geometric representation context within the project.
"
4199;IfcMaterial;"
IfcMaterial is a homogeneous or inhomogeneous
substance that can be used to form elements (physical products or
their components).
IfcMaterial is the basic entity for material
designation and definition; this includes identification by name
and classification (via reference to an external classification),
as well as association of material properties (isotropic or
anisotropic) defined by (subtypes of)
IfcMaterialProperties. An instance of IfcMaterial
may be associated to an element or element type using the
IfcRelAssociatesMaterial relationship. The assignment
might either be direct as a single material information, or
via
- a material layer set
- a material profile set
- a material constituent set
An IfcMaterial may also have presentation information
associated. Such presentation information is provided by
IfcMaterialDefinitionRepresentation, associating line
styles, hatching definitions or surface coloring/rendering
information to a material.
HISTORY˙New entity in IFC2x4
IFC2x4 CHANGE˙ The attributes Description and Category have been added.
"
4206;IfcMaterialDefinition;"
IfcMaterialDefinition is a general supertype for all
material related information items in IFC that have common
material related properties that may include association of
material with some shape parameters or assignments to identified
parts of a component.
There are three ways of assigning materials to a single component or
multiple components; they are characterized as:
- by layer - assigning a material to a layer with constant
thickness
- by profile - assigning a material to a profile with a
constant of varying shape along an extrusion
- by constituents - assigning a material to an identified part
of a component shape; the identification is by a keyword rather than
by a shape parameter
Each instantiable subtype of IfcMaterialDefinition may
have material properties assigned, or have an external
classification of its definition. It can be assigned to either a
subtype of IfcElement, or a subtype of
IfcElementType by using the objectified relationship
IfcRelAssociatesMaterial.
HISTORY˙ New entity in IFC2x4
"
4217;IfcMaterialLayer;"
IfcMaterialLayer is a single and identifiable part of an element which is constructed of a number of layers (one or more). Each IfcMaterialLayer has a constant thickness and is located relative to the referencing IfcMaterialLayerSet along the MlsBase.
EXAMPLE A cavity wall with brick masonry used with
an air gap in between would be modeled using three
IfcMaterialLayer's: [1] Brick, [2] Air gap, [3] Brick. The
inner layer ""Brick"" would have a Name = ""Brick"", an
individual LayerThickness, and potentially a
Category indicating it as ""load bearing"", and a
Priority that controls how this material layer interacts
with other material layers in wall connections.
The IfcMaterialLayer may have a material layer name,
that might be different to the IfcMaterial name
referenced.
EXAMPLE The IfcMaterialLayer name of an
insulation layer can be ""Insulation"", whereas the
IfcMaterial name is ""polystyrene insulating
boards"".
HISTORY New entity in IFC 1.5
IFC2x4 CHANGE The attributes Name, Description, Category, Priority have been added at the end of attribute list. Data type of LayerThickness relaxed to IfcNonNegativeLengthMeasure.
"
4227;IfcMaterialLayerWithOffsets;"
IfcMaterialLayerWithOffsets is a specialization of IfcMaterialLayer enabling definition
of offset values along edges (within the material layer set usage in parent layer set).
It defines the assignment of two offset values for a material
layer in its intended use within a material layer set. Offsets are
applied to the edges of layered elements (that is, in directions
perpendicular to the layer set direction). Offsets shall not be
used in layer set direction, that is, for modelling gaps (or overlaps)
between layers; gaps shall be modeled as layers with appropriate
material assignment for the void.
EXAMPLE At the top of a standard wall,
with shape representation SweptSolid, offset of a given layer can
be specified in the direction of the extrusion (positive Z axis),
applied at the start or end (extruded from bottom to top), and with
a positive (extending above extrusion) or negative (ending below
extrusion).
Take a standard wall with the outer material layer for the
external isolation extending above extrusion by 100mm, but starting
at the same base height. In this case the following values are
set:
- OffsetDirection = .AXIS3.
- OffsetValues[1] = 0.0
- OffsetValues[2] = 100.0 (default unit assumed to
be mm)
HISTORY New Entity in IFC2x4.
Informal propositions
- The OffestDirection shall not be identical to the
LayerSetDirection of the corresponding
IfcMaterialLayerSetUsage
- The attribute ReferenceExtent shall be asserted at the
corresponding IfcMaterialLayerSetUsage
Attribute use definition
The OffsetValues and OffsetDirection correspond to the definitions ReferenceExtent and LayerSetDirection at the IfcMaterialLayerSetUsage.
Figure 289 shows an example of applying the OffsetValues to the material layers of a standard wall.
![]() |
Figure 289 — Material layer with offsets |
"
4234;IfcMaterialLayerSet;"
IfcMaterialLayerSet is a designation by which materials of an element constructed of a number of material layers is known and through which the relative positioning of individual layers can be expressed.
The Material Layer Set Base (MlsBase) describes the axis along
which the material layers are positioned. The MlsBase is positioned
along the reference axis or reference plane of the element
supporting the IfcMaterialLayerSetUsage concept with a
potential offset (see here). The positive Material Layer Set
Direction (MlsDirection) describes the direction by which the
individual material layers, with their material layer thicknesses
are stacked. IfcMaterialLayer's are stacked with no gap,
gaps within a material layer set are expresses as layers by
themselves.
EXAMPLE A cavity brick wall would be modeled as
IfcMaterialLayerSet consisting of three
IfcMaterialLayer's: brick, air cavity and brick. The air
gap is identified, using the IsVentilated flag at
IfcMaterialLayer.
HISTORY New entity in IFC 1.0
IFC2x4 CHANGE Subtyped from IfcMaterialDefinition, the attribute Description
has been added at the end of attribute list.
Attribute use definition
As shown in Figure 285, each IfcMaterialLayerSet implicitly defines a material
layer set base line (MlsBase), to which the start of the first
IfcMaterialLayer is aligned. The total thickness of a
layer set is calculated from the individual layer thicknesses, the
first layer starting from the MlsBase and following layers being
placed on top of the previous (no gaps or overlaps).
![]() |
Figure 285 — Material layer set |
"
4239;IfcMaterialProfileSet;"
IfcMaterialProfileSet is a designation by which individual material(s) of a prismatic element (for example, beam or column) constructed of a single or multiple material profiles is known. If only a single material profile is used (the most typical case) then no CompositeProfile is asserted.
NOTE ˙ In case of multiple MaterialProfiles, the relative positioning of individual profiles in IfcMaterialProfileSet are defined using the concept of IfcCompositeProfileDef in IfcProfileResource schema; otherwise, only one MaterialProfile is given and defined by an individual IfcProfileDef (subtype).
HISTORY˙New Entity in IFC2x4.
"
4244;IfcMaterialProfile;"
IfcMaterialProfile is a single and identifiable part of an element which is constructed of a number of profiles (one or more).
NOTE ˙ In case of multiple MaterialProfiles, the relative positioning of individual profiles in IfcMaterialProfileSet are defined using the concept of IfcCompositeProfileDef in IfcProfileResource schema; otherwise, only one MaterialProfile is given and defined by an individual IfcProfileDef (subtype).
HISTORY˙New Entity in IFC2x4
"
4253;IfcMaterialProfileWithOffsets;"
IfcMaterialProfileWithOffsets is a specialization of IfcMaterialProfile enabling definition offset values for profile start or end in its use in parent material profile set usage.
Relative positions of IfcMaterialProfileWithOffsets in the longitudinal direction of an element can be defined giving offsets at the start and end. This shall not be used for relative positions of individual profiles in the plane of profile definition, which is given in composite profile definition itself. Also, care should be taken especially when used with IfcMaterialProfileSetUsageTapering for correct start and end offset assignement.
HISTORY˙ New Entity in IFC2x4.
"
4255;IfcMaterialConstituentSet;"
IfcMaterialConstituentSet is a collection of individual material constituents, each assigning a material to a part of an element. The parts are only identified by a keyword (as opposed to an IfcMaterialLayerSet or IfcMaterialProfileSet where each part has an individual shape parameter (layer thickness or layer profile).
EXAMPLE The different materials of a window
construction shall be provided for the window lining and the
window glazing. An IfcMaterialConstituentSet is assigned
to the window with two IfcMaterialConstituent's, one with
the Name = 'Lining', one with the Name =
'Glazing'.
NOTE See the ""Material Use Definition"" at the individual
element to which an IfcMaterialConstituentSet may apply
for a required or recommended definition of such
keywords.
HISTORY˙New Entity in IFC2x4.
"
4259;IfcMaterialConstituent;"
IfcMaterialConstituent is a single and identifiable part of an element which is constructed of a number of part (one or more) each having an individual material. The association of the material constituent to the part is provided by a keyword as value of the Name attribute.
NOTE See the ""Material Use Definition"" at the individual element to which an IfcMaterialConstituentSet may apply for a required or recommended definition of such keywords as value for IfcMaterialConstituent.Name.
HISTORY˙New Entity in IFC2x4
"
4266;IfcMaterialRelationship;"
IfcMaterialRelationship defines a relationship between part and whole in material definitions (as in composite materials). The parts, expressed by the set of RelatedMaterials, are material constituents of which a single material aggregate is composed.
HISTORY˙New Entity in IFC2x4
"
4270;IfcMaterialProperties;"
IfcMaterialProperties is defined as an abstract
supertype for entities that apply material properties to material
definitions. A set of material properties that are assigned to an
individual material definiton may be identified by a Name
and a Description.
NOTE The set of material properties can be assigned
to an individual IfcMaterial, a set or composite of
materials (IfcMaterialConstituent,
IfcMaterialConstituentSet), or set or individual material
layer (IfcMaterialLayer, IfcMaterialLayerSet), or
a set or individual material profile (IfcMaterialProfile,
IfcMaterialProfileSet)
The applicable set of material properties is defined at the
subtype IfcExtendedMaterialProperties. It includes
material properties defined in this IFC specification and those
defined as user-defined extended material properties.
HISTORY New Entity in IFC 2x.
IFC2x4 CHANGE The subtypes that represented a fixed list of statically defined material properties, IfcMechanicalMaterialProperties, IfcThermalMaterialProperties, IfcHygroscopicMaterialProperties, IfcGeneralMaterialProperties, IfcOpticalMaterialProperties, IfcWaterProperties, IfcFuelProperties, IfcProductsOfCombustionProperties have been deleted, use the generic IfcExtendedMaterialProperties instead.
"
4275;IfcExtendedMaterialProperties;"
The IfcExtendedMaterialProperties assign a set of
defined material properties to associated material definitions.
This provides a mechanism to assign any material properties to
material. Those material properties that are defined as part of the
IFC specification are provided within the use definitions
below.
NOTE The usage of this entity has changed in
IFC2x4, it is now used to express all material
properties.
The IfcProperty (instantiable subtypes) is used to
express the individual material properties.
HISTORY New entity in Release IFC2x.
IFC2x4 CHANGE The attributes Name and Description are promoted to supertype,
attribute ExtendedProperties has been renamed to Properties.
Extended property use definitions
The following sets of material property definitions are part of
this IFC release:
"
4277;IfcMaterialClassificationRelationship;"
IfcMaterialClassificationRelationship is a relationship assigning classifications to materials.
HISTORY˙ New entity in IFC2x.
IFC2x4 CHANGE˙ The entity IfcMaterialClassificationRelationship is deprecated since IFC2x4 and shall no longer be used. Use IfcExternalReferenceRelationship instead.
"
4280;IfcMaterialLayerSetUsage;"
IfcMaterialLayerSetUsage determines the usage of
IfcMaterialLayerSet in terms of its location and
orientation relative to the associated element geometry. The
location of material layer set shall be compatible with the
building element geometry (that is, material layers shall fit inside
the element geometry). The rules to ensure the compatibility
depend on the type of the building element.
EXAMPLE ˙For a cavity brick wall with shape
representation SweptSolid, the
IfcMaterialLayerSet.TotalThickness shall be equal to the
wall thickness. Also the OffsetFromReferenceLine shall
match the exact positions between the two shape representations
of IfcWallStandardCase, i.e. the
IfcShapeRepresentation's with
RepresentationIdentifier=""Axis"" and
RepresentationIdentifier=""Body"".
NOTE ˙Refer to the implementation guide and agreements for
more information on matching between building element geometry
and material layer set usage.
The IfcMaterialLayerSetUsage is always assigned to an
individual occurrence object only (i.e. to relevant subtypes of
IfcElement). The IfcMaterialLayerSet, referenced by
ForLayerSet can however be shared among several occurrence
objects. If the element type is available (i.e. the relevant
subtype of IfcElementType, then the
IfcMaterialLayerSet can be assigned to the type object.
The assignment between a˙subtype of IfcElement and the
IfcMaterialLayerSetUsage is handled by
IfcRelAssociatesMaterial.
Use definition
The IfcMaterialLayerSetUsage is primarily intended to
be associated with planar building elements having a constant
thickness. With further agreements on the interpretation of
LayerSetDirection, the usage can be extended also to other
cases, e.g. to curved building elements, provided that the
material layer thicknesses are constant.
Generally, an element may be layered in any of its primary
directions, denoted by its x, y or z axis. The geometry use
definitions at each˙specific types of building element will
determine the applicable˙LayerSetDirection.
The following examples illustrate how the IfcMaterialLayerSetUsage attributes (LayerSetDirection, DirectionSense, OffsetFromReferenceLine) can
be used in different cases. The normative material use definitions are documented at each element (how these shall be used).
Figure 286 shows an example of the use of IfcMaterialLayerSetUsage aligned to the axis of a wall.
EXAMPLE For a standard wall with extruded
geometric representation (vertical extrusion), the layer set
direction will be perpendicular to extrusion direction,
and˙can be derived from the direction of the wall
axis. With the DirectionSense(positive in
this example) the individual IfcMaterialLayers are
assigned consecutively right-to-left or left-to-right. For a
curved wall, ""direction denoting the wall thickness"" can be
derived from the direction of the wall axis, and it will remain
perpendicular to the wall path. The
DirectionSense˙applies as well.
NOTE According to the IfcWallStandardCase material use
definition the LayerSetDirection for
IfcWallStandardCase is always AXIS2 (i.e. along the
y-axis), as shown in this example.
![]() |
Figure 286 — Material layer set usage for wall |
Figure 287 shows an example of the use of IfcMaterialLayerSetUsage aligned to a slab.
EXAMPLE ˙For a slab with perpendicular
extruded geometric representation, the LayerSetDirection
will coincide with the extrusion direction (in positive or
negative sense). In this example, the material layer set base is
the extruded profile and consistent with the
IfcExtrudedAreaSolid.Position,˙with the
DirectionSensebeing positive, the
individual IfcMaterialLayers are built up from the base
towards positive z direction in this case.
NOTE ˙According to the IfcSlabStandardCase
material use definition the LayerSetDirection for
IfcSlabStandardCase is always AXIS3 (i.e. along the
z-axis).
![]() |
Figure 287 — Material layer set usage for slab |
Figure 288 shows an example of the use of IfcMaterialLayerSetUsage aligned to a roof slab with non-perpendicular extrusion.
EXAMPLE ˙For a slab with non-perpendicular
extruded geometric representation, the guidelines above apply as
well. The material layer thickness and the
OffsetFromReferenceLine is always measured
perpendicularly, even if the extrusion direction is not
perpendicular. Therefore the total material layer thickness is
not equal to the extrusion depth of the
geometry.
![]() |
Figure 288 — Material layer set usage for roof slab |
"
4286;IfcMaterialUsageDefinition;"
IfcMaterialUsageDefinition is a general supertype for all
material related information items in IFC that have occurrence
specific assignment parameters to assign a set of materials with
shape parameters to a reference geometry item of that
component.
There are two ways of assigning a set of materials with shape
parameters:
- a layer set to a reference curve - assigning a material layer
set with material layers having a sequence and thickness
parameter to a reference curve of an element - represented by the
'Axis' shape representation of that element
- a profile set to a cardinal point - assigning a material
profile set with assigned profile geometry and insertion points
to a reference curve by an offset, called ""cardinal point"" - the
reference curve is represented by the 'Axis' shape representation
of that element
Each instantiable subtype of IfcMaterialUsageDefinition
has to be assigned to a subtype of IfcElement by using the
objectified relationship IfcRelAssociatesMaterial; it is
only valid in conjunction with an element occurrence.
HISTORY˙ New entity in IFC2x4
Informal proposition
- It is illegal to assign a subtype of
IfcMaterialUsageDefinition to a subtype of
IfcElementType, it shall only be assigned to an element
occurrence.
"
4290;IfcMaterialProfileSetUsage;"
IfcMaterialProfileSetUsage determines the usage of IfcMaterialProfileSet in terms of its location relative to the associated element geometry. The location of a material profile set shall be compatible with the building element geometry (that is, material profiles shall fit inside the element geometry). The rules to ensure the compatibility depend on the type of the building element. For building elements with shape representations which are based on extruded solids, this is accomplished by referring to the identical profile definition in the shape model as in the material profile set.
NOTE ˙ Refer to the implementation guide and agreements for more information on matching between building element geometry and material profile set usage.
NOTE ˙ The referenced IfcMaterialProfileSet may represent a single material
profile, or a composite profile with two or more material profiles.
HISTORY˙New Entity in IFC2x4.
"
4295;IfcMaterialProfileSetUsageTapering;"
IfcMaterialProfileSetUsageTapering specifies dual material profile sets in association with tapered prismatic (beam- or column-like) elements.
HISTORY˙ New entity in IFC 2x4
Usage with tapered building elements
The inherited attribute ForProfileSet specifies the
profile and material at the start of the member,
ForProfileEndSet at its end. Start and end correspond to
the extrusion direction in the shape model of the shape
representation of the element or element type.
Both material profile sets should refer to the same material,
that is, only differ with respect to their profiles.
Usage with structural analysis curve members
IfcMaterialProfileSetUsageTapering may be used with the
structural analysis idealization
(IfcStructuralCurveMember) of uniform members as well as
of tapered members.
In case of uniform members, ForProfileSet and
ForProfileEndSet refer to the same material profile set.
In case of tapered members, ForProfileSet specifies the
profile and material at the start of the member,
ForProfileEndSet at its end. Start and end correspond to
the edge direction in the topological representation of the curve
member.
"
4304;IfcMaterialList;"
IfcMaterialList is a list of the different materials
that are used in an element.
NOTE: The class IfcMaterialList will
normally be used where an element is described at a more abstract
level. For example, for an architectural specification writer,
the only information that may be needed about a concrete column
is that it contains concrete, reinforcing steel and mild steel
ligatures. It shall not be used for elements consisting of
material layers when the different layers can be defined and the
class IfcMaterialLayerSet can be used. Also,
IfcMaterialList shall not be used for elements consisting
of a single identifiable material (for example, to represent anisotropic
material).
IFC2x4 CHANGE˙ The entity IfcMaterialList is deprecated and shall no longer
be used. Use IfcMaterialConstituentSet instead.
"
4367;IfcDerivedUnit;"
Definition from ISO/CD 10303-41:1992: A derived unit is an expression of units.
EXAMPLE: Newton per square millimetre is a derived unit.
NOTE: Corresponding ISO 10303 name: derived_unit, please refer to ISO/IS 10303-41 for the final definition of the formal standard.
HISTORY: New entity in IFC Release 1.5.1.
"
4374;IfcDerivedUnitElement;"
Definition from ISO/CD 10303-41:1992: A derived unit element is one of the unit quantities
which makes up a derived unit.
EXAMPLE: Newtons per square millimetre is a derived unit.
It has two elements, Newton whose exponent has a value of 1 and millimetre whose exponent is -2.
NOTE: Corresponding ISO 10303 name: derived_unit_element, please refer to ISO/IS 10303-41 for the final definition of the formal standard.
HISTORY New entity in IFC Release 1.5.1.
"
4377;IfcNamedUnit;"
Definition from ISO/CD 10303-41:1992: A named unit is a unit quantity associated with the word, or group of words, by which the unit is identified.
NOTE Corresponding ISO 10303 name: named_unit, please refer to ISO/IS 10303-41 for the final definition of the formal standard.
HISTORY New type in IFC Release 1.5.1.
"
4384;IfcContextDependentUnit;"
Definition from ISO/CD 10303-41:1992: A context dependent unit is a unit which is not related to the SI system.
NOTE The number of parts in an assembly is a physical quantity measured in units that may be called ""parts"" but which cannot be related to an SI unit.
NOTE Corresponding ISO 10303 name: context_dependent_unit, please refer to ISO/IS 10303-41 for the final definition of the formal standard.
HISTORY New entity in IFC Release 1.5.1.
"
4388;IfcConversionBasedUnit;"
Definition from ISO/CD 10303-41:1992: A conversion based unit is a unit that is defined based on a measure with unit.
NOTE Corresponding ISO 10303 name: conversion_based_unit, please refer to ISO/IS 10303-41 for the final definition of the formal standard.
HISTORY New entity in IFC Release 1.5.1.
IFC 2x3 change: standard names of typical units added.
IFC 2x4 change: further names added: square inch, square foot, square mile, square yard, cubic inch, cubic foot, cubic yard, fluid ounce UK/US, ton UK/US, degree.
Example: An inch is a converted unit. It is from the Imperial system, its name is ""inch"" and it can be related to the si unit, millimetre, through a measure with unit whose value is 25.4 millimetre. A foot is also a converted unit. It is from the Imperial system, its name is ""foot"" and it can be related to an IfcSIUnit, millimetre, either directly or through the unit called ""inch"". Note that several US customary units differ from Imperial units (nonmetric English units) of the same name.
To identify some commonly used conversion based units, the standard designations (case insensitive) for the Name attribute include the following:
| Name | Description |
| 'inch' | Length measure equal to 25.4 mm |
| 'foot' | Length measure equal to 304.8 mm |
| 'yard' | Length measure equal to 914 mm |
| 'mile' | Length measure equal to 1609 m |
| 'square inch' | Area measure equal to 0.0006452 square meters |
| 'square foot' | Area measure equal to 0.09290 square meters |
| 'square yard' | Area measure equal to 0.83612736 square meters |
| 'acre' | Area measure equal to 4046.86 square meters |
| 'square mile' | Area measure equal to 2 588 881 square meters |
| 'cubic inch' | Volume measure equal to 0.00001639 cubic meters |
| 'cubic foot' | Volume measure equal to 0.02832 cubic meters |
| 'cubic yard' | Volume measure equal to 0.7636 cubic meters |
| 'litre' | Volume measure equal to 0.001 cubic meters |
| 'fluid ounce UK' | Volume measure equal to 0.0000284130625 cubic meters |
| 'fluid ounce US' | Volume measure equal to 0.00002957353 cubic meters |
| 'pint UK' | Volume measure equal to 0.000568 cubic meters |
| 'pint US' | Volume measure equal to 0.000473 cubic meters |
| 'gallon UK' | Volume measure equal to 0.004546 cubic meters |
| 'gallon US' | Volume measure equal to 0.003785 cubic meters |
| 'degree' | Angle measure equal to π/180 rad |
| 'ounce' | Mass measure equal to 28.35 g |
| 'pound' | Mass measure equal to 0.454 kg |
| 'ton UK' | Mass measure equal to 1016.0469088 kg, also known as long ton, gross ton, shipper's ton |
| 'ton US' | Mass measure equal to 907.18474 kg, also known as short ton, net ton |
| 'lbf' | Force measure equal to 4.4482216153 N, pound-force |
| 'kip' | Force measure equal to 4448.2216153 N, kilopound-force |
| 'psi' | Pressure measure equal to 6894.7572932 Pa, pound-force per square inch |
| 'ksi' | Pressure measure equal to 6894757.2932 Pa, kilopound-force per square inch |
| 'minute' | Time measure equal to 60 s |
| 'hour' | Time measure equal to 3600 s |
| 'day' | Time measure equal to 86400 s |
| 'btu' | Energy measure equal to 1055.056 J, British Thermal Unit |
"
4393;IfcConversionBasedUnitWithOffset;"
IfcConversionBasedUnitWithOffset is a unit which is converted from another unit by applying a conversion factor and an offset.
HISTORY New entity in IFC 2x4.
Example: The temperature unit Fahrenheit is based on the temperature unit Kelvin as follows:
f = k · 1.8 – 459.67
wherein k is an absolute temperature expressed in Kelvin and f is the same temperature in Fahrenheit. The following entity instances provide Fahrenheit as a unit:
IfcConversionBasedUnitWithOffset(
IfcDimensionalExponents(0, 0, 0, 0, 1, 0, 0),
THERMODYNAMICTEMPERATUREUNIT,
'Fahrenheit',
IfcMeasureWithUnit(
IfcThermodynamicTemperatureMeasure(1.8),
IfcSiUnit(THERMODYNAMICTEMPERATUREUNIT, ?, KELVIN)),
-459.67);
"
4395;IfcMeasureWithUnit;"
Definition from ISO/CD 10303-41:1992: A measure with unit is the specification of a physical quantity as defined in ISO 31 (clause 2).
IfcMeasureWithUnit has two usages:
1. For representing measure value together with its unit on the entity type attribute level; thus
overriding the IFC model global unit assignments.
2. For conversion based unit to give the conversion rate and its base.
NOTE Corresponding ISO 10303 name: measure_with_unit, please refer to ISO/IS 10303-41 for the final definition of the formal standard.
HISTORY New entity in IFC Release 1.5.1.
"
4567;IfcSIUnit;"
Definition from ISO/CD 10303-41:1992: An SI unit is the fixed quantity used as a standard in terms of which items are measured as defined by ISO 1000 (clause 2).
IfcSIUnit covers both standard base SI units such as meter and second, and derived SI units such as Pascal, square meter and cubic meter.
NOTE Corresponding ISO 10303 name: si_unit, please refer to ISO/IS 10303-41 for the final definition of the formal standard.
HISTORY New entity in IFC Release 1.5.1.
"
4619;IfcDimensionalExponents;"
Definition from ISO/CD 10303-41:1992: The dimensionality of any quantity can be expressed as a product of powers of the dimensions of base quantities.
The dimensional exponents entity defines the powers of the dimensions of the base quantities. All the physical
quantities are founded on seven base quantities (ISO 31 (clause 2)).
NOTE: Length, mass, time, electric current, thermodynamic temperature, amount of substance,
and luminous intensity are the seven base quantities.
EXAMPLE: A length of 2 millimetres has a length exponent of 1. The remaining exponents
are equal to 0.
EXAMPLE: A velocity of 2 millimetres per second has a length exponent of 1 and
a time exponent of -1. The remaining exponents are equal to 0.
NOTE Corresponding STEP name: dimensional_exponents, please refer to ISO/IS 10303-41
for the final definition of the formal standard.
HISTORY New entity in IFC Release 1.5.1.
"
4709;IfcMonetaryUnit;"
IfcMonetaryUnit is a unit to define currency for money.
HISTORY: New entity in IFC Release 2x.
IFC2x4 CHANGE: Type of the attribute Currency changed.
"
4711;IfcUnitAssignment;"
IfcUnitAssignment indicates a set of units which may be assigned. Within an IfcUnitAssigment each unit definition shall be unique; that is, there shall be no redundant unit definitions for the same unit type such as length unit or area unit. For currencies, there shall be only a single IfcMonetaryUnit within an IfcUnitAssignment.
NOTE A project (IfcProject) has a unit assignment which establishes a set of units which will be used globally within the project, if not otherwise defined. Other objects may have local unit assignments if there is a requirement for them to make use of units which do not fall within the project unit assignment.
HISTORY New entity in IFC Release 1.5.1.
"
4719;IfcFillAreaStyleHatching;"
Definition from ISO/CD 10303-46:1992: The fill area style hatching defines a styled pattern of curves for hatching an annotation fill area or a surface.
The IfcFillAreaStyleHatching is used to define simple, vector-based hatching patterns, based on styled straight lines. The curve font, color and thickness is given by the HatchLineAppearance, the angle by the HatchLineAngle and the distance to the next hatch line by StartOfNextHatchLine, being either an offset distance or a vector.
NOTE If the hatch pattern involves two (potentially crossing) rows of hatch lines, then two instances of IfcFillAreaStyleHatching should be assigned to the IfcFillAreaStyle. Both share the same (virtual) point of origin of the hatching that is used by the reference hatch line (or the PointOfReferenceHatchLine if there is an offset).
For better control of the hatching appearance, when using hatch lines with other fonts then continuous, the PatternStart allows to offset the start of the curve font pattern along the reference hatch line (if not given, the PatternStart is at zero distance from the virtual point of origin). If the reference hatch line does not go through the origin (of the virtual hatching coordinate system), it can be offset by using the PatternStart PointOfReferenceHatchLine.
NOTE The coordinates of the PatternStart and the PointOfReferenceHatchLine are given relative to the assumed 0., 0. virtual point of origin at which the hatch pattern is later positioned by the FillStyleTarget point at IfcAnnotationFillAreaOccurrence. The measure values are given in global drawing length units and apply to the target plot scale for the scale depended representation subcontext.
NOTE The use of PointOfReferenceHatchLine is deprecated.
Figure 292 illustrates hatch attributes.
NOTE Corresponding ISO 10303 name: fill_area_style_hatching. Please refer to ISO/IS 10303-46:1994, p. 108 for the final definition of the formal standard.
HISTORY New entity in IFC2x2.
IFC2x3 CHANGE The IfcFillAreaStyleHatching has been changed by making the attributes PatternStart and PointOfReferenceHatchLine OPTIONAL. The attribute StartOfNextHatchLine has changed to a SELECT with the additional choice of IfcPositiveLengthMeasure. Upward compatibility for file based exchange is guaranteed.
"
4728;IfcCurveStyle;"
Definition from ISO/CD 10303-46:1992: A curve style specifies the visual appearance of curves.
An IfcCurveStyle provides the style table for presentation information assigned to geometric curves. The style is defined by a color, a font and a width. The IfcCurveStyle defines curve patterns as model patterns, that is, the distance between visible and invisible segments of curve patterns are given in model space dimensions (that have to be scaled using the target plot scale).
Styles are intended to be shared by multiple IfcStyledItem's, assigning the style to occurrences of (subtypes of) IfcGeometricRepresentationItem's. Measures given to a font pattern or a curve width are given in global drawing length units.
NOTE global units are defined at the single IfcProject instance, given by UnitsInContext:IfcUnitAssignment, the same units are used for the geometric representation items and for the style definitions.
The measure values for font pattern and curve width apply to the model space with a target plot scale provided for the correct appearance in the default plot scale.. For different scale and projection dependent curve styles a different instance of IfcCurveStyle needs to be used by IfcPresentationStyleAssignment for different IfcGeometricRepresentationSubContext dependent representations.
NOTE the target plot scale is given by IfcGeometricRepresentationSubContext.TargetScale.
An IfcCurveStyle can be assigned to IfcGeometricRepresentationItem's via the IfcPresentationStyleAssignment through an intermediate IfcStyledItem or IfcAnnotationCurveOccurrence.
NOTE Corresponding ISO 10303 name: curve_style. Please refer to ISO/IS 10303-46:1994 for the final definition of the formal standard.
HISTORY New entity in IFC2x2.
"
4733;IfcPresentationStyle;"
IfcPresentationStyle is an abstract generalization of style table for presentation information assigned to geometric representation items. It includes styles for curves, areas, surfaces, text and symbols. Style information may include colour, hatching, rendering, and text fonts.
Each subtype of IfcPresentationStyle can be assigned to IfcGeometricRepresentationItem's via the IfcPresentationStyleAssignment through an intermediate IfcStyledItem or one of its subtypes.
HISTORY New entity in IFC2x3.
"
4740;IfcTextStyle;"
Definition from ISO/CD 10303-46:1992: The text style is a presentation style for annotation text.
The IfcTextStyle provides the text style table for presentation information assigned to text literals. The style is defined by color, text font characteristics, and text box characteristics. The definitions are based upon:
- definitions from ISO/IS 10303-46:1994 for (old) vector based and monospace text.
- definitions from Cascading Style Sheets, level 1, W3C Recommendation 17 Dec 1996, revised 11 Jan 1999, CSS1, for all true type text. The use of the CSS1 definitions is the preferred way to represent text styles.
An IfcTextStyle, when representing (old) vector based and monospace text, is instantiated with:
- TextCharacterAppearance:: IfcTextStyleForDefinedFont (with BackgroundColour = NIL)
- TextStyle:: IfcTextStyleWithBoxCharacteristics
- TextFontStyle:: IfcDraughtingPreDefinedTextFont or IfcExternallyDefinedTextFont
An IfcTextStyle, when representing (new) true type text, based on CSS1 definitions, is instantiated with:
- TextCharacterAppearance:: IfcTextStyleForDefinedFont
- TextStyle:: IfcTextStyleTextModel
- TextFontStyle:: IfcTextStyleFontModel
An IfcTextStyle can be assigned to IfcTextLiteral via the IfcPresentationStyleAssignment through an intermediate IfcAnnotationTextOccurrence.
NOTE Corresponding ISO 10303 name: text_style. Please refer to ISO/IS 10303-46:1994 for the final definition of the formal standard. In order to avoid ANDOR subtype relationships, the IfcTextBlockStyleSelect has been introduced that allows the combination of a text style as having box characteristic, and/or having spacing, or having none of those additional properties.
NOTE Corresponding CSS1 definitions are: Font properties (font-family, font-style, font-variant, font-weight, font-size), Color and background properties (color, background-color) and Text properties (word-spacing, letter-spacing, text-decoration, text-transform, text-align, text-indent, line-height).
HISTORY New entity in IFC2x2.
IFC2x3 CHANGE The IfcTextStyle has been changed by adding TextFontStyle and different data types for TextStyle and IfcCharacterStyleSelect.
"
4746;IfcTextStyleForDefinedFont;"
Definition from ISO/CD 10303-46:1992: A text style for defined font is a character glyph style for pre-defined or externally defined text fonts.
Definition from CSS1 (W3C Recommendation): These properties describe the color (often called foreground color) and background of an element (i.e. the surface onto which the content is rendered). One can set a background color.
NOTE The CSS1 definition allows also for a background image. This has not been incorporated into IFC.
The IfcTextStyleForDefinedFont combines the text font color with an optional background color, that fills the text box, defined by the planar extent given to the text literal.
NOTE Corresponding ISO 10303 name: text_style_for_defined_font. Please refer to ISO/IS
10303-46:1994, p.122 for the final definition of the formal standard. The attribute BackgroundColour
has been added.
NOTE Corresponding CSS1 definitions are Color and background properties (color, background-color).
HISTORY New entity in IFC2x3.
IFC2x3 CHANGE The IfcTextStyleForDefinedFont has been added and replaces IfcColour at the IfcCharacterStyleSelect.
"
4749;IfcPreDefinedCurveFont;"
Definition from ISO/CD 10303-46:1992: The predefined curve font type is an abstract supertype provided to define an application specific curve font. The name label shall be constrained in the application protocol to values that are given specific meaning for curve fonts in that application protocol.
NOTE: The IfcPreDefinedCurveFont is an abstract entity, subtypes of it provide the predefined curve font by agreement of the values of the inherited Name attribute. Currently the only subtype provided is IfcDraughtingPreDefinedCurveFont.
NOTE: Corresponding ISO 10303 name: pre_defined_curve_font. Please refer to ISO/IS 10303-46:1994, p. 103 for the final definition of the formal standard.
HISTORY: New entity in IFC2x2.
"
4751;IfcDraughtingPreDefinedCurveFont;"
The draughting predefined curve font type defines a selection of widely used curve fonts for draughting purposes by name.
NOTE The IfcDraughtingPreDefinedCurveFont is an entity that had been adopted from ISO 10303, Industrial automation systems and integration—Product data representation and exchange, Part 46 Technical Corrigendum 2: Integrated generic resources: Visual presentation.
Figure 291 (from ISO 10303-46 TC2) illustrates predefined curve fonts.
![]() |
Figure 291 — Draughting predefined curve font |
NOTE If the IfcDraughtingPreDefinedCurveFont is used within an IfcCurveStyleFontAndScaling then the segment and space lengths that are given in the table are as such for the scale factor 1.0
NOTE Corresponding ISO 10303 name: pre_defined_curve_font. Please refer to ISO/IS 10303-46:1994 TC2, page 12 for the final definition of the formal standard.
HISTORY New entity in IFC2x2.
"
4756;IfcTextStyleWithBoxCharacteristics;"
The text style with box characteristics allows the presentation of annotated text by specifying the characteristics of the character boxes of the text and the spacing between the character boxes.
NOTE The IfcTextStyleWithBoxCharacteristics is an entity that had been adopted from ISO 10303, Industrial automation systems and integration—Product data representation and exchange, Part 46: Integrated generic resources: Visual presentation.
The IfcTextStyleWithBoxCharacteristics is mainly used to provide some compatibility with ISO10303. Its usage is restricted to monospace text fonts (having uniform character boxes) and simple vector based text fonts. For true text fonts however the use of IfcTextStyleTextModel is required.
Figure 296 (from ISO 10303-46, page 91) illustrates angles. Figure 297 illustrates attribute use.
![]() |
![]() |
Figure 296 — Text style box angles |
Figure 297 — Text style box attributes |
NOTE Corresponding ISO 10303 name: text_style_with_box_characteristics. Please refer to ISO/IS 10303-46:1994, p. 123 for the final definition of the formal standard. The four optional attributes BoxHeight, BoxWidth, BoxSlantAngle, BoxRotateAngle are included directly at the entity, and are not handled through the box_characteristic_select selecting box_height, box_width, box_slant_angle, box_rotate_angle, each being defined types.
The CharacterSpacing attribute has been added from ISO/IS 10303-46:1994 entity text_style_with_spacing.
HISTORY New entity in IFC2x2.
IFC2x3 CHANGE The attribute item CharacterSpacing has been added.
"
4769;IfcTextStyleTextModel;"
Definition from CSS1 (W3C Recommendation): The properties defined in the text model affect the visual presentation of characters, spaces, words, and paragraphs.
The IfcTextStyleTextModel combines all text style properties, that affect the presentation of a text literal within a given extent. It includes the spacing between characters and words, the horizontal and vertical alignment of the text within the planar box of the extent, decorations (like underline), transformations of the literal (like uppercase), and the height of each text line within a multi-line text block.
NOTE Corresponding CSS1 definitions are Text properties (word-spacing, letter-spacing, text-decoration, vertical-align, text-transform, text-align, text-indent, line-height).
HISTORY New entity in IFC2x3.
"
4783;IfcFillAreaStyle;"
Definition from ISO/CD 10303-46:1992: The style for filling visible curve segments, annotation fill areas or surfaces with tiles or hatches.
An IfcFillAreaStyle provides the style table for presentation information assigned to annotation fill areas or surfaces for hatching and tiling. The IfcFillAreaStyle defines hatches as model hatches, that is, the distance between hatch lines, or the curve patterns of hatch lines are given in model space dimensions (that have to be scaled using the target plot scale). The IfcFillAreaStyle allows for the following combinations of defining the style of hatching and tiling:
- Solid fill for areas and surfaces by only assigning IfcColour to the set of FillStyles. It then provides the background colour for the filled area or surface.
NOTE Color information of surfaces for rendering is assigned by using IfcSurfaceStyle, not by using IfcFillAreaStyle.
- Vector based hatching for areas and surfaces based on a single row of hatch lines by assigning a single instance of IfcFillAreaStyleHatching to the set of FillStyles.
- If an instance of IfcColour is assigned in addition to the set of FillStyles, it provides the background colour for the hatching.
- Vector based hatching for areas and surfaces based on two (potentially crossing) rows of hatch lines by assigning two instances of IfcFillAreaStyleHatching to the set of FillStyles.
- If an instance of IfcColour is assigned in addition to the set of FillStyles, it provides the background colour for the hatching.
NOTE Assigning more then two instances of IfcFillAreaStyleHatching to define three or more rows of hatch lines is not encouraged.
- Tiling for areas and surfaces by assigning a single instance of IfcFillAreaStyleTiles to the set of FillStyles.
- If an instance of IfcColour is assigned in addition to the set of FillStyles, it provides the background colour for the tiling.
IFC2x3 NOTE The use of IfcFillAreaStyleTiles is discouraged., as its definition might change is future releases.
- Externally defined hatch style by assigning a single instance of IfcExternallyDefinedHatchStyle to the set of FillStyles.
- If an instance of IfcColour is assigned in addition to the set of FillStyles, it provides the background colour for the hatching.
Measures given to a hatch or tile pattern are given in global drawing length units.
NOTE Global units are defined at the single IfcProject instance, given by UnitsInContext:IfcUnitAssignment, the same units are used for the geometric representation items and for the style definitions.
The measure values for hatch or tile pattern apply to the model space with a target plot scale provided for the correct appearance in the default plot scale. For different scale and projection dependent fill area styles a different instance of IfcFillAreaStyle needs to be used by IfcPresentationStyleAssignment for different IfcGeometricRepresentationSubContext dependent representations.
NOTE the target plot scale is given by IfcGeometricRepresentationSubContext.TargetScale.
An IfcFillAreaStyle can be assigned to IfcFillArea via the IfcPresentationStyleAssignment through an intermediate IfcStyledItem or subtype IfcAnnotationFillAreaOccurrence.
NOTE Corresponding ISO 10303 name: fill_area_style. Please refer to ISO/IS 10303-46:1994 for the final definition of the formal standard.
HISTORY New entity in IFC2x2.
"
4793;IfcFillAreaStyleTiles;"
Definition from ISO/CD 10303-46:1992: The fill area style tiles defines a two dimensional tile to be used for the filling of annotation fill areas or other closed regions. The content of a tile is defined by the tile set, and the placement of each tile determined by the filling pattern which indicates how to place tiles next to each other. Tiles or parts of tiles outside of the annotation fill area or closed region shall be clipped at the of the area or region.
NOTE Corresponding ISO 10303 name: fill_area_style_tiles. Please refer to ISO/IS 10303-46:1994 for the final definition of the formal standard.
HISTORY New entity in IFC2x2.
"
4797;IfcOneDirectionRepeatFactor;"
Definition from ISO/CD 10303-46:1992: A one time repeat factor is a vector used in the fill area style hatching and fill area style tiles entities for determining the origin of the repeated hatch line relative to the origin of the previous hatch line, Given the initial position of any hatch line, the one direction repeat factor determines two new positions according to the equation:
I + k * R k X{-1,1}
NOTE: Corresponding ISO 10303 name: one_direction_repeat_factor. Please refer to ISO/IS 10303-46:1994, p. 112 for the final definition of the formal standard.
HISTORY: New entity in IFC2x2.
"
4800;IfcTwoDirectionRepeatFactor;"
Definition from ISO/CD 10303-46:1992: A two direction repeat factor combines two vectors which are used in the fill area style tiles entity for determining the shape and relative location of tiles. Given the initial position of any tile, the two direction repeat factor determines eight new positions according to the equation:
k1* R1 + k2* R2
k X{-1,1} ![]()
NOTE Corresponding ISO 10303 name: two_direction_repeat_factor. Please refer to ISO/IS 10303-46:1994 for the final definition of the formal standard.
HISTORY New entity in IFC2x2.
"
4804;IfcFillAreaStyleTileSymbolWithStyle;"
The fill area style tile symbol with style is a symbol that is used as a tile within an annotated tiling.
NOTE: The IfcFillAreaStyleTileSymbolWithStyle is an entity that had been adopted from ISO 10303, Industrial automation systems and integration—Product data representation and exchange, Part 46: Integrated generic resources: Visual presentation.
NOTE: Corresponding ISO 10303 name: fill_area_style_tile_symbol_with_style. Please refer to ISO/IS 10303-46:1994 for the final definition of the formal standard.
HISTORY: New entity in IFC2x2.
"
4806;IfcStyledItem;"
Definition from ISO/CD 10303-46:1992: The styled item is an assignment of style for presentation to a geometric representation item as it is used in a representation.
NOTE Corresponding ISO 10303 name: styled_item. Please refer to ISO/IS 10303-46:1994 for the final definition of the formal standard.
The IfcStyledItem holds presentation style information for products, either explicitly for an IfcGeometricRepresentationItem being part of an IfcShapeRepresentation assigned to a product, or by assigning presentation information to IfcMaterial being assigned as other representation for a product.
- If the IfcStyledItem is used within a reference from an IfcProductDefinitionShape then one Item shall be provided.
- If the IfcStyledItem is used within a reference from an IfcMaterialDefinitionRepresentation then no Item shall be provided.
HISTORY New entity in IFC2x2.
IFC2x2 Addendum 1 CHANGE The entity IfcStyledItem has been made non abstract and the attribute Name added.
IFC2x3 CHANGE The attribute Item has been made optional, upward compatibility for file
based exchange is guaranteed.
IFC2x4 CHANGE The subtype IfcAnnotationOccurrence and its subtypes are deleted. Use IfcStyledItem for all instantiations. The data type of Styles has been changed to IfcStyleAssignmentSelect
Use Definition
Figure 293 illustrates use of IfcStyledItem for the two usage examples:
- As a presentation for a geometric representation item
- As a presentation for a material definition
NOTE The new IfcStyleAssignmentSelect allows the direct assignment styles, such as IfcCurveStyle, IfcSurfaceStyle without using the intermediate IfcPresentationStyleAssignment
![]() |
Figure 293 — Styled item |
"
4814;IfcPresentationStyleAssignment;"
Definition from ISO/CD 10303-46:1992: The presentation style assignment is a set of styles which are assigned to styled items for the purpose of presenting these styled items.
NOTE Corresponding ISO 10303 name: presentation_style_assignment. Please refer to ISO/IS 10303-46:1994 for the final definition of the formal standard.
HISTORY New entity in Release IFC2x2.
"
4825;IfcSymbolStyle;"
Definition from ISO/CD 10303-46:1992: The symbol style is the presentation style that indicates the presentation of annotation symbols.
NOTE: Corresponding ISO 10303 name: symbol_style. Please refer to ISO/IS 10303-46:1994, p. 124 for the final definition of the formal standard.
HISTORY: New entity in Release IFC2x2.
"
4829;IfcSurfaceStyle;"
IfcSurfaceStyle is an assignment of one or many surface style elements to a surface, defined by subtypes of IfcSurface, IfcFaceBasedSurfaceModel, IfcShellBasedSurfaceModel, or by subtypes of IfcSolidModel. The positive direction of the surface normal relates to the positive side. In case of solids the outside of the solid is to be taken as positive side.
NOTE: The surface style is often referred to as material definition in rendering applications.
NOTE Corresponding ISO 10303 entity: surface_style_usage and surface_side_style. Please refer to ISO/IS 10303-46:1994 for the final definition of the formal standard. The surface style definition in regard to support of rendering has been greatly expanded beyond the scope of ISO/IS 10303-46.
HISTORY New Entity in IFC 2.x.
"
4847;IfcSurfaceStyleShading;"
Definition from ISO/CD 10303-46:1992: The surface style rendering allows the realistic visualization of surfaces referring to rendering techniques based on the laws of physics and mathematics.
The entity IfcSurfaceStyleShading allows for colour information used for shading, whereas subtypes provide data for more sophisticated rendering techniques. The surface colour is used for colouring or simple shading of the assigned surfaces.
NOTE Corresponding ISO 10303 entity: surface_style_rendering. Please refer to ISO/IS 10303-46:1994 for the final definition of the formal standard. No rendering method is defined for each surface style (such as constant, colour, dot or normal shading), therefore the attribute rendering_method has been omitted.
HISTORY: New entity in IFC 2x.
"
4850;IfcSurfaceStyleRendering;"
IfcSurfaceStyleRendering holds the properties for visualization related to a particular surface side style.
It allows rendering properties to be defined by:
- a transparency component (Transparency attribute)
- a colour component (SurfaceColour attribute inherited from IfcSurfaceStyleShading)
- a reflectance component, given either by
- applying reflectance factors to the surface colour:
- diffuse component (SurfaceColour * DiffuseFactor)
- transmission component (SurfaceColour * TransmissionFactor)
- diffuse transmission component (SurfaceColour * DiffuseTransmissionFactor)
- reflection component (SurfaceColour * ReflectionFactor)
- specular component (SurfaceColour * SpecularFactor attribute together with SpecularHighlight)
- explicitly defining such factors as colours (DiffuseColour, TransmissionColour, DiffuseTransmissionColour, ReflectionColour and SpecularColour)
- a displacement component, currently only given by a texture map with the TextureType = bump
- a coverage component, currently only given by the alpha component of the texture map (2 or 4 component colour texture)
NOTE: The inherited attribute SurfaceColour is treated as the ambient colour and specifies how much ambient light from light sources this surface shall reflect. Ambient light is omnidirectional and depends only on the number of light sources, not their positions with respect to the surface.
NOTE: If the reflectance method, as given by the IfcReflectanceMethodEnum is ""GLASS"", the transmission factor controls the level of transparency in the glass, In this case the transparency factor is interpreted as transmission factor.
NOTE: Both Transparency and TransmissionColour (or factor) are included, the following definitions apply:
- Transparency is the ratio of the transmitted flux in a solid angle of 2 * PI sr (one hemisphere). It is a simple colour filtration that does not account for refraction.
- Transmission factor of a material is the ratio of transmitted flux in a given solid angle to the transmitted flux of a completely diffuse material with 100% transmission in the same solid angle. It is the portion of light that goes through the material and may be refracted.
NOTE: IFC 2x2 adds additional capability for presentation of physically accurate illuminance on surfaces. VRML type rendering and rendering based on ISO 10303-46 continues to be supported by a subset of the information. For reflectance equations and further information about the surface style properties and its processing, see:
- ISO/IEC 14772-1: 1997: The Virtual Reality Modeling Language
NOTE: The definition of IfcSurfaceStyleRenderingProperties includes the definitions as found in ISO 10303-46:1994, in particular of:
- surface_style_rendering_with_properties
- surface_style_rendering_ambient
- surface_style_rendering_ambient_diffuse
- surface_style_rendering_ambient_diffuse_specular
- surface_style_transparent
In addition to the attributes as defined in ISO 10303-46, (ambient_reflectance, diffuse_reflectance, specular_reflectance, specular_exponent, and specular_colour), the current IFC definition adds other colours, reflectance factors and specular roughness.
HISTORY: New Entity in IFC 2x.
"
4879;IfcSurfaceStyleLighting;"
IfcSurfaceStyleLighting is a container class for properties for calculation of physically exact illuminance related to a particular surface style.
Figure 294 shows the reflection and transmission components from an incident ray. The sum of the components for reflection and transmission is a value of 1.0 denoting that the incident ray is completely decomposed into reflection and transmission components. Each value of reflection and transmission is therefore within the range 0.0 to 1.0.
![]() |
Figure 294 — Surface style lighting |
All these factors can be measured physically and are ratios for the red, green and blue part of the light. These properties are defined in the model as Type IfcColorRGB with a factor for each colour.
EXAMPLE A green glass transmits only green light, so its transmission factor is 0.0 for red, between 0.0 and 1.0 for green and 0.0 for blue. A green surface reflects only green light, so the reflectance factor is 0.0 for red, between 0.0 and 1.0 for green and 0.0 for blue.
HISTORY New entity in IFC 2x2.
"
4884;IfcSurfaceStyleWithTextures;"
The entity IfcSurfaceStyleWithTextures allows to include image textures in surface styles. These image textures can be applied repeating across the surface or mapped with a particular scale upon the surface.
The entity IfcSurfaceStyleWithTextures is part of the surface style table for presentation information assigned to surfaces for shading, rendering and lighting with textures. The mapping of the texture onto the surface or the solid is determined by the texture coordinates, in absense of an IfcTextureCoordinate assigned to each surface texture, a default mapping of the texture to the geometric face or surface applies.
Surface textures included in the IfcSurfaceStyleWithTextures are two dimensional map formats. They define 2D images that contain an array of colour values describing the texture. Depending on the number of IfcSurfaceTextures being included in the list of Textures the IfcSurfaceStyleWithTextures either describes a single texture, or a multi texture.
- single texture: a single surface texture is applied to the styled geometric item (entirely or partly) with optional repetition and texture transformation
- multi texture: two or more surface textures are applied to the styled geometric item (entirely or partly) with optional repetition, texture transformation or texture coordinate mapping being specific for each texture.
Informal proposition
- Only one instance of IfcSurfaceStyleWithTextures shall be referenced by an IfcStyledItem and be assigned to an IfcGeometricRepresentationItem
NOTE The definitions of texturing within this standard have been developed in dependence on the texture component of X3D. See ISO/IEC 19775-1.2:2008 X3D Architecture and base components Edition 2, Part 1, 18 Texturing component for the definitions in the international standard.
HISTORY New entity in IFC2x2.
IFC2x3 CHANGE inverse attribute HasTextureCoordinates deleted.
"
4886;IfcSurfaceTexture;"
An IfcSurfaceTexture provides a 2-dimensional
image-based texture map. It can either be given by referencing an
external image file through an URL reference
(IfcImageTexture), including the image file as a blob
(long binary) into the data set (IfcBlobTexture), or by
explicitly including an array of pixels
(IfcPixelTexture).
The following definitions from ISO/IEC 19775-1 X3D Architecture
and base components (X3D Specification)
apply:
- Texture: An image
used in a texture map to create visual appearance effects when
applied to geometry nodes.
- Texture map: A
texture plus the general parameters necessary for mapping the
texture to geometry.
Texture are defined by 2D images that contain an array of colour
values describing the texture. The texture values are interpreted
differently depending on the number of components in the texture
and the specifics of the image format. In general, texture may be
described using one of the following forms:
- Intensity textures (one-component)
- Intensity plus alpha opacity textures (two-component)
- Full RGB textures (three-component)
- Full RGB plus alpha opacity textures (four-component)
NOTE Image formats specify an alpha opacity, not transparency (where alpha = 1 - transparency).
Figure 295 illustrates the texture coordinate system.
![]() |
Figure 295 — Surface texture coordinates |
The following definitions from ISO/IEC 19775-1 X3D Architecture and base components (X3D Specification) on texture coordinates apply:
- Texture maps are defined in a 2D coordinate system (s, t) that ranges from [0.0, 1.0] in both directions. The bottom edge of the image corresponds to the S-axis of the texture map, and left edge of the image corresponds to the T-axis of the texture map. The lower-left pixel of the image corresponds to s=0, t=0, and the top-right pixel of the image corresponds to s=1, t=1. Texture maps may be viewed as two dimensional colour functions that, given an (s, t) coordinate, return a colour value colour(s, t).
If multiple surface textures are included in the
IfcSurfaceStyleWithTextures applying them to a geometric
item, a mode and optional parameters can be included that blending
operations.
The RepeatS and RepeatT Boolean flags control
whether the texture map is repeated outside the [0.0, 1.0] texture
coordinate range, when applied to a geometric surface, or clamped
to lie within the [0.0, 1.0] range. The TextureTransform
applies a 2D non-uniform transformation to the texture before it is
applied to a geometric surface.
The following definitions from ISO/IEC 19775-1 X3D Architecture
and base components (X3D Specification)
apply:
- These parameters
support changes to the size, orientation, and position of textures
on shapes. Note that these operations appear reversed when viewed
on the surface of geometry. For example, a scale value of (2
2) will scale the texture coordinates and have the net effect of
shrinking the texture size by a factor of 2 (texture coordinates
are twice as large and thus cause the texture to repeat). A
translation of (0.5 0.0) translates the texture coordinates +.5
units along the S-axis and has the net effect of translating the
texture −0.5 along the S-axis on the geometry's surface. A
rotation of π/2 of the texture coordinates results in a
−π/2 rotation of the texture on the geometry.
- The center
field specifies a translation offset in texture coordinate space
about which the rotation and scale fields are
applied. The scale field specifies a scaling factor in S and
T of the texture coordinates about the center point.
scale values shall be in the range (−∞,∞).
The rotation field specifies a rotation in radians of the
texture coordinates about the center point after the scale
has been applied. A positive rotation value makes the texture
coordinates rotate counterclockwise about the centre, thereby
rotating the appearance of the texture itself clockwise. The
translation field specifies a translation of the texture
coordinates.
The following conventions
apply:
- center =
TextureTransform.LocalOrigin;
rotation = TextureTransform.Axis1
scale S = TextureTransform.Scale
scale T = TextureTransform.Scale2
NOTE The definitions of texturing within this standard have been developed in dependence on the texture component of X3D. See ISO/IEC 19775-1.2:2008 X3D Architecture and base components Edition 2, Part 1, 18 Texturing component for the definitions in the international standard.
HISTORY New entity in IFC 2x2.
IFC2x4 CHANGE Attribute TextureType replaces by Mode, attributes Parameter and MapsTo aded, new inverse attribute UsedInStyle.
"
4897;IfcPixelTexture;"
An IfcPixelTexture provides a 2D image-based texture map as an explicit array of pixel values (list of Pixel binary attributes). In contrary to the IfcImageTexture the IfcPixelTexture holds a 2 dimensional list of pixel color
(and opacity) directly, instead of referencing to an URL.
The following definitions from ISO/IEC 19775-1 X3D Architecture and base components (X3D Specification) apply:
- The PixelTexture node defines a 2D image-based texture map as an explicit array of pixel values (image field) and parameters controlling tiling repetition of the texture onto geometry.
- Texture maps are defined in a 2D coordinate system (s, t) that ranges from 0.0 to 1.0 in both directions. The bottom edge of the pixel image corresponds to the S-axis of the texture map, and left edge of the pixel image corresponds to the T-axis of the texture map. The lower-left pixel of the pixel image corresponds to s=0.0, t=0.0, and the top-right pixel of the image corresponds to s = 1.0, t = 1.0.
- The Image field specifies a single uncompressed 2-dimensional pixel image. Image fields contain three integers representing the width, height and number of components in the image, followed by width×height hexadecimal values representing the pixels in the image. Pixel values are limited to 256 levels of intensity (that is, 0x00-0xFF hexadecimal).
- A one-component image specifies one-byte hexadecimal value representing the intensity of the image. For example, 0xFF is full intensity in hexadecimal (255 in decimal), 0x00 is no intensity (0 in decimal).
- A two-component image specifies the intensity in the first
(high) byte and the alpha opacity in the second (low) byte.
- Pixels in a three-component image specify the red component in the first (high) byte, followed by the green and blue components (for example, 0xFF0000 is red, 0x00FF00 is green, 0x0000FF is blue).
- Four-component images specify the alpha opacity byte after red/green/blue (e.g., 0x0000FF80 is semi-transparent blue). A value of 00 is completely transparent, FF is completely opaque, 80 is semi-transparent.
- Note that alpha equals (1.0 -transparency), if alpha and transparency each range from 0.0 to 1.0.
HISTORY: New class in IFC2x2.
"
4907;IfcImageTexture;"
An IfcImageTexture provides a 2-dimensional texture that can be applied to a surface of an geometric item and that provides lighting parameters of a surface onto which it is mapped. The texture is provided as an image file at an external location for which an URL is provided.
The following definitions from ISO/IEC 19775-1 X3D Architecture and base components (X3D Specification) apply:
- The ImageTexture node defines a texture map by specifying an image file and general parameters for mapping to geometry.
- The texture is read from the URL specified by the url field. When the url field contains no [resolvable] values, texturing is disabled. Browsers shall support the JPEG and PNG (see ISO/IEC 15948) image file formats.
- Texture nodes that require support for the PNG image format shall interpret the PNG pixel formats in the following way:
- Greyscale pixels without alpha or simple transparency are treated as intensity textures.
- >Greyscale pixels with alpha or simple transparency are treated as intensity plus alpha textures.
- RGB pixels without alpha channel or simple transparency are treated as full RGB textures.
- RGB pixels with alpha channel or simple transparency are treated as full RGB plus alpha textures.
- If the image specifies colours as indexed-colour (that is, palettes or colourmaps), the following semantics should be used (note that `greyscale' refers to a palette entry with equal red, green, and blue values):
- If all the colours in the palette are greyscale and there is no transparency chunk, it is treated as an intensity texture.
- If all the colours in the palette are greyscale and there is a transparency chunk, it is treated as an intensity plus opacity texture.
- >If any colour in the palette is not grey and there is no transparency chunk, it is treated as a full RGB texture.
- If any colour in the palette is not grey and there is a transparency chunk, it is treated as a full RGB plus alpha texture.
- Texture nodes that require support for JPEG files shall interpret JPEG files as follows:
- Greyscale files (number of components equals 1) are treated as intensity textures.
- YCbCr files are treated as full RGB textures.
- No other JPEG file types are required. It is recommended that other JPEG files are treated as a full RGB textures.
- Texture nodes that recommend support for GIF files shall follow the applicable semantics described above for the PNG format.
The Uniform Resource Locator (URL) is a form of an URI and specified in RFC1738 by IETF. It supports resources located on a particular server being accessed by a particular protocol (usually http), and resources located at a local machine.
NOTE Exchange files following the ifcZIP convention may include a sub directory structure for image resources to be stored together with the product data set.
NOTE The definitions of texturing within this standard have been developed in dependence on the texture component of X3D. See ISO/IEC 19775-1.2:2008 X3D Architecture and base components Edition 2, Part 1, 18 Texturing component for the definitions in the international standard.
HISTORY New entity in Release IFC2x2.
"
4909;IfcExternallyDefinedSurfaceStyle;"
IfcExternallyDefinedSurfaceStyle is a definition of a surface style through referencing an external source, such as a material library for rendering information.
NOTE In order to achieve expected results, the externally defined surface style should normally only be given in addition to an explicitly defined surface styles.
HISTORY New entity in IFC2x2.
IFC2x3 CHANGE The spelling has been corrected from IfcExternallyDefinedSufaceStyle with no upward compatibility.
"
4910;IfcExternallyDefinedHatchStyle;"
Definition from ISO/CD 10303-46:1992: The externally defined hatch style is an entity which makes an external reference to a hatching style.
NOTE: The allowable values for the name source and item reference, by which the externally defined hatch style is identified, need to be determined by implementer agreements.
NOTE: Corresponding ISO 10303 name: fill_style_select. Please refer to ISO/IS 10303-46:1994 for
the final definition of the formal standard.
HISTORY: New entity in IFC2x2.
"
4911;IfcBlobTexture;"
An IfcBlobTexture provides a 2-dimensional distribution of the lighting parameters of a surface onto which it is mapped. The texture itself is given as a single binary blob, representing the content of a pixel format file. The file format of the pixel file is given by the RasterFormat attribute and allowable formats are guided by where rule SupportedRasterFormat.
NOTE Toolbox specific implementations of the binary datatype may restrict the maximum length of the binary blob to capture the raster file content.
For interpretation of the texture nodes see IfcImageTexture definition.
HISTORY New class in IFC2x3.
IFC2x4 CHANGE Data type of RasterCode has been corrected to BINARY.
"
4916;IfcSurfaceStyleRefraction;"
IfcSurfaceStyleRefraction extends the surface style lighting, or the surface style rendering definition for properties for calculation of physically exact illuminance by adding seldomly used properties. Currently this includes the refraction index (by which the light ray refracts when passing through a prism) and the dispersion factor (or Abbe constant) which takes into account the wavelength dependency of the refraction.
NOTE: If such refraction properties are used, the IfcSurfaceStyle should include within its set of Styles (depending on whether rendering or lighting is used) an instance of IfcSurfaceStyleLighting and IfcSurfaceStyleRefraction, or an instance of IfcSurfaceStyleRendering and IfcSurfaceStyleRefraction.
HISTORY: New entity in IFC 2x2.
"
4925;IfcCurveStyleFont;"
Definition from ISO/CD 10303-46:1992: A curve style font combines several curve style font pattern entities into a more complex pattern. The resulting pattern is repeated along the curve.
NOTE: Corresponding ISO 10303 name: curve_style_font. Please refer to ISO/IS 10303-46:1994 for the final definition of the formal standard.
HISTORY: New entity in IFC2x2.
"
4928;IfcCurveStyleFontPattern;"
Definition from ISO/CD 10303-46:1992: A curve style font pattern is a pair of visible and invisible curve segment length measures in presentation area units.
NOTE Corresponding ISO 10303 name: curve_style_font_pattern. Please refer to ISO/IS 10303-46:1994 for the final definition of the formal standard.
HISTORY New entity in IFC2x2.
"
4932;IfcCurveStyleFontAndScaling;"
Definition from ISO/CD 10303-46:1992: A curve style font and scaling is a curve style font and a scalar factor for that font, so that a given curve style font may be applied at various scales.
The IfcCurveStyleFontAndScaling allows for the reuse of the same curve style definition in several sizes. The definition of the CurveFontScale is the scaling of a base curve style pattern to be used as a new or derived curve style pattern.
NOTE The CurveFontScale should not be mixed up with the target plot scale.
An example for IfcCurveStyleFontAndScaling is the sizing of a basic curve style dash pattern 'dash' (visible 0.01m, invisible 0.005m) into 'dash large' with CurveFontScale = 2 (resulting in visible 0.02m, invisible 0.01m), and into 'dash small' with CurveFontScale = 0.5 (resulting in visible 0.005m, invisible 0.0025m).
NOTE Corresponding ISO 10303 name: curve_style_font_and_scaling. Please refer to ISO/IS 10303-46:1994 for the final definition of the formal standard.
HISTORY New entity in IFC2x2.
"
4941;IfcTextLiteral;"
The text literal is a geometric representation item which describes a text string using a string literal and additional position and path information.
NOTE The IfcTextLiteral is an entity that had been adopted from ISO 10303, Industrial automation systems and integration—Product data representation and exchange.
NOTE Corresponding ISO 10303 name: text_literal. Please refer to ISO/IS 10303-46:1994 for the
final definition of the formal standard. The attributes font and alignment have been removed as those should be handled by the text style.
HISTORY New entity in IFC2x2.
IFC2x3 CHANGE The IfcTextLiteral has been changed by removing Font and Alignment.
"
4946;IfcAnnotationFillArea;"
Definition from ISO/CD 10303-46:1992: An annotation fill area is a set of curves that may be filled with hatching, colour or tiling. The annotation fill are is described by boundaries which consist of non-intersecting, non-self-intersecting closed curves. These curves form the boundary of planar areas to be filled according to the style for the annotation fill area.
NOTE: A curve that is not surrounded by any other curve is a border between an unfilled area on the outside and a filled area on the inside. Another curve may surround an unfilled area if it is surrounded by another curve whose inside is a filled area.
Figure 300 (from ISO 10303-46) illustrates annotation fill area.
![]() |
Figure 300 — Annotation fill area |
NOTE Corresponding ISO 10303 name: annotation_fill_area. Please refer to ISO/IS 10303-46:1994 for the final definition of the formal standard.
The IfcAnnotationFillArea defines an area by a definite OuterBoundary, that might include InnerBoundaries. The areas defined by the InnerBoundaries are excluded from applying the fill area style.
Informal Proposition:
- Any curve that describes an inner boundary shall not intersect with, nor include, another curve defining an inner boundary.
- The curve defining the outer boundary shall not intersect with any curve defining an inner boundary, nor shall it be surrounded by a curve defining an inner boundary.
HISTORY New entity in IFC2x2.
IFC2x3 CHANGE The two attributes OuterBoundary and InnerBoundaries are added and replace the previous single boundary.
"
4949;IfcDefinedSymbol;"
A defined symbol is a symbolic representation that gets its shape information by an established convention, either through a predefined symbol, or an externally defined symbol.
NOTE: The IfcDefinedSymbol is an entity that had been adopted from ISO 10303, Industrial automation systems and integration—Product data representation and exchange, Part 46: Integrated generic resources: Visual presentation.
NOTE Corresponding ISO 10303 name: defined_symbol. The target attribute used the 2d Cartesian transformation operator, including the non-uniform subtype, which is available in IFC (instead of the symbol_target). Please refer to ISO/IS 10303-46:1994 for the final definition of the formal standard.
HISTORY New entity in IFC2x2.
"
4955;IfcPreDefinedSymbol;"
A predefined symbol is a symbol that gets its shape information by a conforming name that is specified within subtypes of the entity.
NOTE: The IfcPreDefinedSymbol is an entity that had been adopted from ISO 10303, Industrial automation systems and integration—Product data representation and exchange, Part 46: Integrated generic resources: Visual presentation.
NOTE Corresponding ISO 10303 name: pre_defined_symbol. Please refer to ISO/IS 10303-46:1994 for the final definition of the formal standard.
HISTORY New entity in IFC2x2.
"
4956;IfcExternallyDefinedSymbol;"
An externally defined symbol is a symbol that gets its shape information by an agreed reference to an external source.
NOTE: The allowable symbol names and sources have to be established by implementers agreements.
NOTE: The IfcExternallyDefinedSymbol is an entity that had been adopted from ISO 10303, Industrial automation systems and integration—Product data representation and exchange, Part 46: Integrated generic resources: Visual presentation.
NOTE Corresponding ISO 10303 name: externally_defined_symbol. Please refer to ISO/IS 10303-46:1994 for the final definition of the formal standard.
HISTORY New entity in IFC2x2.
"
4957;IfcTextureCoordinate;"
The IfcTextureCoordinate a an abstract supertype of the different kinds to apply texture coordinates to geometries. For vertex based geometries an explicit assignment of 2D texture vertices to the 3D geometry points is supported by the subtype IfcTextureMap, in addition there can be a procedural description of how texture coordinates shall be applied to geometric items. If no IfcTextureCoordinate is provided for the IfcSurfaceTexture, the default mapping shall be used.
See relevant subtypes of IfcGeometricRepresentationItem for default texture mapping description.
NOTE The definitions of texturing within this standard have been developed in dependence on the texture component of X3D. See ISO/IEC 19775-1.2:2008 X3D Architecture and base components Edition 2, Part 1, 18 Texturing component for the definitions in the international standard.
HISTORY New entity in IFC2x2.
IFC2x3 CHANGE The attribute Texture is deleted.
IFC2x4 CHANGE The inverse attribute AnnotatedSurface is deleted, and the inverse AppliesTextures is added.
"
4961;IfcTextureCoordinateGenerator;"
The IfcTextureCoordinateGenerator describes a procedurally defined mapping function with input parameter to map 2D texture coordinates to 3D geometry vertices. The allowable Mode values and input Parameter need to be agreed upon in view definitions and implementer agreements.
It is recommended to use the texture coordinate generation modes as defined in X3D.
The following definitions from ISO/IEC 19775-1 X3D Architecture and base components (X3D Specification) apply:
- The TextureCoordinateGenerator supports the automatic generation of texture coordinates for geometric shapes.
- The mode field describes the algorithm used to compute texture coordinates.
- SPHERE,
- CAMERASPACENORMAL,
- CAMERASPACEPOSITION,
- CAMERASPACEREFLECTIONVECTOR,
- SPHERE-LOCAL,
- COORD,
- COORD-EYE,
- NOISE,
- NOISE-EYE,
- SPHERE-REFLECT,
- SPHERE-REFLECT-LOCAL
NOTE The definitions of texturing within this standard have been developed in dependence on the texture component of X3D. See ISO/IEC 19775-1.2:2008 X3D Architecture and base components Edition 2, Part 1, 18 Texturing component for the definitions in the international standard.
HISTORY New entity in IFC2x2.
IFC2x2 Addendum 2 CHANGE The attribute Texturehas been deleted.
"
4964;IfcTextureMap;"
An IfcTextureMap provides the mapping of the
2-dimensional texture coordinates to the surface onto which it is
mapped. It is used for mapping the texture to surfaces of vertex
based geometry models, such as
- IfcFacetedBrep
- IfcFacetedBrepWithVoids
- IfcFaceBasedSurfaceModel
- IfcShellBasedSurfaceModel
The IfcTextureMap has a list of TextureVertex,
that corresponds to the points of the face bound of the vertex
based geometry item. The corresponding pair of lists is:
- the list of Polygon of type IfcCartesianPoint,
and
- the list of Vertices of type
IfcTextureVertex.
Each IfcTextureVertex (given as S, T coordinates of the
2-dimension texture coordinate system) corresponds to the geometric
coordinates of the IfcCartesianPoint (given as 3-dimension
X, Y, and Z coordinates within the object coordinate system of the
geometric item).
The following definitions from ISO/IEC 19775-1 X3D Architecture
and base components (X3D Specification)
apply:
- The TextureCoordinate node is a geometry property node that
specifies a set of 2D texture coordinates used by vertex-based
geometry nodes to map textures to vertices.
NOTE In contrary to the
X3D vertext based geometry, for example IndexedFaceSet and
ElevationGrid, the vertext based geometry in IFC may include inner
loops. The areas of inner loops have to be cut-out from the texture
applied to the outer loop.
Figure 301 illustrates applying a texture map to a vertex based geometry.
![]() |
Figure 301 — Texture map |
HISTORY New entity in IFC2x2.
IFC2x3 CHANGE The attribute Texture is deleted, and the attribute TextureMaps is added.
IFC2x4 CHANGE The attribute TextureMap is replaced by Vertices, and the attribute AppliedTo is added.
Informal propositions:
- The FaceBound referenced in AppliedTo shall be used by the vertex based geometry, to which this texture map is assigned to by through the IfcStyledItem.
"
4967;IfcTextureVertex;"
An IfcTextureVertex is a list of 2 (S, T) texture coordinates.
The following additional definitions from ISO 19775 apply:
Each vertex-based geometry node uses a set of 2D texture
coordinates that map textures to vertices. Texture map values (
ImageTexture, PixelTexture) range from [0.0, 1.0] along the S-axis and
T-axis. However, texture coordinate values may be in the range
(-∞,∞). Texture coordinates identify a location
(and thus a
colour value) in the texture map. The horizontal coordinate S is
specified first, followed by the vertical coordinate T. If the texture
map is repeated in a given direction (S-axis or T-axis), a texture
coordinate C (s or t) is mapped into a texture map that has N pixels in
the given direction as follows:
Texture map location = (C - floor(C)) × N
If the texture map is not
repeated, the texture coordinates are
clamped to the 0.0 to 1.0 range as follows:
Texture map location = N, if C > 1.0,
= 0.0, if C < 0.0,
= C × N, if 0.0 ≤ C ≤ 1.0.
Texture coordinates may be transformed (scaled, rotated, translated) by supplying a TextureTransform as a component of the texture's definition.
HISTORY: New entity in IFC 2x2.
"
4969;IfcTextLiteralWithExtent;"
The text literal with extent is a text literal with the additional explicit information of the planar extent (or surrounding text box). An alignment attribute defines, how the text box is aligned to the placement and how it may expand.
NOTE The IfcTextLiteralWithExtent is an entity that had been adopted from ISO 10303, Industrial automation systems and integration—Product data representation and exchange, Part 46: Integrated generic resources: Visual presentation.
NOTE Corresponding ISO 10303 name: text_literal_with_extent. Please refer to ISO/IS 10303-46:1994 for the final definition of the formal standard.
HISTORY New entity in IFC2x2.
IFC2x3 CHANGE The IfcTextLiteralWithExtent has been changed by adding BoxAlignment.
"
4981;IfcLightSource;"
Definition from ISO/CD 10303-46:1992: The light source entity is determined by the reflectance specified in the surface style rendering. Lighting is applied on a surface by surface basis: no interactions between surfaces such as shadows or reflections are defined.
NOTE: Corresponding STEP entity: light_source. Please refer to ISO/IS 10303-46:1994, p. 31 for the final definition of the formal standard.
NOTE: In addition to the attributes as defined in ISO10303-46 the following additional properties from ISO/IEC 14772-1:1997 (VRML) are added: ambientIntensity and Intensity. The attribute Name has been added as well (as it is not inherited via representation_item).
HISTORY: This is a new Entity in IFC 2x, renamed and enhanced in IFC2x2.
"
4990;IfcLightSourceAmbient;"
Definition from ISO/CD 10303-46:1992: The light source ambient entity is a subtype of light source. It lights a surface independent of the surface's orientation and position.
NOTE: Corresponding ISO 10303 entity: light_source_ambient. Please refer to ISO/IS 10303-46:1994, p. 31 for the final definition of the formal standard.
NOTE: In addition to the attributes as defined in ISO 10303-46 the additional property from ISO/IEC 14772-1:1997 (VRML) AmbientIntensity is inherited from the supertype.
HISTORY: This is a new entity in IFC 2x, renamed and enhanced in IFC2x2.
"
4991;IfcLightSourceDirectional;"
Definition from ISO/CD 10303-46:1992: The light source directional is a subtype of light source. This entity has a light source direction. With a conceptual origin at infinity, all the rays of the light are parallel to this direction. This kind of light source lights a surface based on the surface's orientation, but not position.
Definition from ISO/IEC 14772-1:1997: The directional light node defines a directional light source that illuminates along rays parallel to a given 3-dimensional vector. Directional light nodes do not attenuate with distance. Directional light nodes are specified in the local coordinate system and are affected by ancestor transformations.
NOTE: Corresponding ISO 10303 entity: light_source_directional. Please refer to ISO/IS 10303-46:1994, p. 32 for the final definition of the formal standard.
NOTE: In addition to the attributes as defined in ISO 10303-46 the additional property from ISO/IEC 14772-1:1997 (VRML) AmbientIntensity and Intensity are inherited from the supertype.
HISTORY: This is a new entity in IFC 2x, renamed and enhanced in IFC2x2.
"
4993;IfcLightSourcePositional;"
Definition from ISO/CD 10303-46:1992: The light source positional entity is a subtype of light source. This entity has a light source position and attenuation coefficients. A positional light source affects a surface based on the surface's orientation and position.
Definition from ISO/IEC 14772-1:1997: The Point light node specifies a point light source at a 3D location in the local coordinate system. A point light source emits light equally in all directions; that is, it is omnidirectional. Point light nodes are specified in the local coordinate system and are affected by ancestor transformations.
Point light node's illumination falls off with distance as specified by three attenuation coefficients. The attenuation factor is
1/max(attenuation[0] + attenuation[1] × r + attenuation[2] × r 2 , 1),
where r is the distance from the light to the surface being illuminated. The default is no attenuation. An attenuation value of (0, 0, 0) is identical to (1, 0, 0). Attenuation values shall be greater than or equal to zero.
NOTE: Corresponding ISO 10303 entity: light_source_positional. Please refer to ISO/IS 10303-46:1994, p. 32 for the final definition of the formal standard.
NOTE: In addition to the attributes as defined in ISO10303-46 the additional property from ISO/IEC 14772-1:1997 (VRML) Radius and QuadricAttenuation are added to this subtype and the AmbientIntensity and Intensity are inherited from the supertype.
HISTORY: This is a new entity in IFC 2x, renamed and enhanced in IFC2x2.
"
5000;IfcLightSourceSpot;"
Definition from ISO/CD 10303-46:1992: The light source spot entity is a subtype of light source. Spot light source entities have a light source colour, position, direction, attenuation coefficients, concentration exponent, and spread angle. If a point lies outside the cone of influence of a light source of this type as determined by the light source position, direction and spread angle its colour is not affected by that light source.
NOTE The IfcLightSourceSpot adds the BeamWidthAngle which defines the inner cone in which the light source emits light at uniform full intensity. The light source's emission intensity drops off from the inner solid angle (BeamWidthAngle) to the outer solid angle (SpreadAngle).
Definition from ISO/IEC 14772-1:1997: The Spot light node defines a light source that emits light from a specific point along a specific direction vector and constrained within a solid angle. Spot lights may illuminate geometry nodes that respond to light sources and intersect the solid angle defined by the Spot light. Spot light nodes are specified in the local coordinate system and are affected by ancestors' transformations.
Figure 304 (from VRML97) shows the definition of spot light.
![]() |
Figure 304 — Light source spot |
NOTE Corresponding ISO 10303 entity: light_source_spot. Please refer to ISO/IS 10303-46:1994, p. 33 for the final definition of the formal standard.
NOTE In addition to the attributes as defined in ISO10303-46 the additional property from ISO/IEC 14772-1:1997 (VRML) Radius, BeamWidth, and QuadricAttenuation are added to this subtype and the AmbientIntensity and Intensity are inherited from the supertype.
HISTORY This is a new entity in IFC 2x, renamed and enhanced in IFC2x2.
"
5005;IfcLightSourceGoniometric;"
IfcLightSourceGoniometric defines a light source for which exact lighting data is available. It specifies the type of a light emitter, defines the position and orientation of a light distribution curve and the data concerning lamp and photometric information.
Figure 303 shows an example of a light emitter having two light sources (of type IfcLightSourceGoniometric).
![]() |
Figure 303 — Light source goniometric |
HISTORY: New entity in IFC2x2.
"
5027;IfcLightIntensityDistribution;"
IfcLightIntensityDistribution defines the the luminous intensity of a light source that changes according to the direction of the ray. It is based on some standardized light distribution curves, which are defined by the LightDistributionCurve attribute.
New entity in IFC2x2.
"
5035;IfcLightDistributionData;"
IfcLightDistributionData defines the luminous intensity of a light source given at a particular main plane angle. It is based on some standardized light distribution curves; the MainPlaneAngle is either the
- A angle; if the IfcLightDistributionCurveEnum is set to TYPE_A
- B angle; if the IfcLightDistributionCurveEnum is set to TYPE_B
- C angle; if the IfcLightDistributionCurveEnum is set to TYPE_C
For each MainPlaneAngle (considered as being the row of a table) a list of SecondaryPlaneAngle's are given (considered to be the columns of a table). They are either the:
- α angle; if the IfcLightDistributionCurveEnum is set to TYPE_A
- β angle; if the IfcLightDistributionCurveEnum is set to TYPE_B
- γ angle; if the IfcLightDistributionCurveEnum is set to TYPE_C
For each pair of MainPlaneAngle and SecondaryPlaneAngle the LuminousIntensity is provided (the unit is given by the IfcUnitAssignment referring to the LuminousIntensityDistributionUnit, normally cd/klm).
HISTORY: New entity in IFC2x2.
"
5039;IfcPresentationLayerAssignment;"
The presentation layer assignment provides the layer name (and optionally a description and an identifier) for a collection of geometric representation items. The IfcPresentationLayerAssignment corresponds to the term ""CAD Layer"" and is used mainly for grouping and visibility control.
NOTE The use of presentation layer shall be restricted to simple grouping and displaying purposes.
Visibility and access control and layer style assignment (colour, line style, line width) is handled by the subtype IfcPresentationLayerAssignmentWithStyle.
NOTE Corresponding ISO 10303 name: presentation layer assignment. Please refer to ISO/IS 10303-46:1994, p. 36 for the final definition of the formal standard.
HISTORY New entity in IFC2x2.
Attribute use definition
Figure 305 illustrates assignment of items by shape representation or representation item. The set of AssignedItems can either include a whole shape representation, or individual geometric representation items. If both, the IfcShapeRepresentation has a layer assignment, and an individual geometric representation item in the set of IfcShapeRepresentation.Items, then the layer assignment of the IfcGeometricRepresentationItem overides the layer assignment of the IfcShapeRepresentation.
![]() |
Figure 305 — Presentation layer assignment |
"
5046;IfcPresentationLayerWithStyle;"
An IfcPresentationLayerAssignmentWithStyle extends the presentation layer assignment with capabilities to define visibility control, access control and common style information.
The visibility control allows to define a layer to be either 'on' or 'off', and/or 'frozen' or 'not frozen'. The access control allows to block graphical entities from manipulations by setting a layer to be either 'blocked' or 'not blocked'. Common style information can be given to the layer.
NOTE Style information assigned to layers is often restricted to 'layer colour', 'curve font', and/or 'curve width'. These styles are assigned by using the IfcCurveStyle within the LayerStyles.
NOTE: If a styled item is assigned to a layer using the IfcPresentationLayerAssignmentWithStyle, it inherits the style information from the layer. In this case, it should omit its own style information. If the styled item has style information assigned (such as by IfcCurveStyle, IfcFillAreaStyle, IfcTextStyle, IfcSurfaceStyle, IfcSymbolStyle), then it overrides the style provided by the IfcPresentationLayerAssignmentWithStyle.
NOTE The IfcPresentationLayerAssignmentWithStyle extends the presentation_layer_assignment entity as defined in ISO/IS 10303-46:1994, p. 36.
HISTORY New entity in IFC2x2.
IFC2x3 CHANGE The attributes have been modified without upward compatibility.
"
5056;IfcParameterizedProfileDef;"
The parameterized profile definition
defines a 2D position coordinate system to which the parameters of the
different profiles relate to. All profiles are defined centric to the
origin of the position coordinate system, or more specific, the origin
[0.,0.] shall be in the center of the bounding box of the profile.
The Position attribute of IfcParameterizedProfileDef
is used to position the profile within the XY plane of the underlying
coordinate system of the swept surface geometry, the swept area
solid or the sectioned spine. It can be used to position the profile at
any point which becomes the origin [0.,0.,0.] of the extruded
or rotated surface or solid.
The Position attribute should not be used if the transformation
can be specified in a containing object instead. In particular, this
applies if the IfcParameterizedProfileDef is referenced as
SweptArea in subtypes of IfcSweptAreaSolid or as
CrossSections in IfcSectionedSpine.
Several subtypes of IfcParameterizedProfileDef provide
shape parameters which are optional. Sending systems should always
provide values for these parameters if possible. If these parameters
are left unspecified, receiving systems may retrieve values for them
by external reference (if a reference to an external document or library
is given; see guidance at IfcProfileDef), or estimate them, or
simply assume zero values.
HISTORY New entity in IFC2x2.
IFC2x Platform CHANGE The IfcParameterizedProfileDef
is introduced as an intermediate new abstract entity that unifies the
definition and usage of the position coordinate system for all
parameterized profiles. The Position attribute has been removed at all
subtypes (like IfcRectangleProfileDef, IfcCircleProfileDef,
etc.).
IFC2x3 CHANGE All profile origins are now in the center
of the bounding box.
IFC2x4 CHANGE Position attribute made optional (default: identity transformation).
Several radius parameters in subtypes have been changed from optional IfcPositiveLengthMeasure (assumed default: 0.) to optional IfcNonNegativeLengthMeasure (default: unspecified). This change allows to explicitly specify zero radius. Sending systems shall export 0. values if parameters are known to be 0.
Subtypes IfcCraneRailAShapeProfileDef and IfcCraneRailFShapeProfileDef deleted. Rail profiles shall be modeled as IfcArbitraryClosedProfileDef or as IfcAsymmetricIShapeProfileDef together with appropriate external reference.
"
5068;IfcProfileDef;"
IfcProfileDef
is the supertype of all definitions of standard and arbitrary profiles
within IFC. It is used to define a standard set of commonly used
section profiles by their parameters or by their explicit curve geometry.
- Parameterized profiles are 2D primitives, which are used within the industry to describe cross
sections by a description of its parameters.
- Arbitrary profiles are cross
sections defined by an outer boundary as bounded curve, which may also
include holes, defined by inner boundaries.
- Derived profiles, based on a
transformation of a parent profile, are also part of the profile
definitions available.
- In addition composite
profiles can be defined, which include two or more profile definitions
to define the resulting profile.
HISTORY New class in IFC Release 1.5, the capabilities have been extended in IFC Release 2x.
Profiles can now support swept surfaces and swept area solids with
inner boundaries. It had been renamed from IfcAttDrivenProfileDef.
IFC2x4 CHANGE Changed from ABSTRACT to non-abstract for uses which do not
require an explicitly defined geometry. Added inverse attributes HasProperties and HasExternalReference.
Use in material association
Beams, columns, and similarly shaped building elements and their type objects may
be associated with a section profile definition, combined with material definition,
by means of IfcRelAssociatesMaterial together with IfcMaterialProfileSet
and IfcMaterialProfileSetUsage. This way, building elements and element types
with same section and material can share a common section profile definition and
association.
The profile definition in material association is required to be consistent with
shape representations of the respective building elements.
A higher-level description of spatial aligment of the section profile of a member
(such as centered, bottom-left, in the geometric centroid, and more) can be provided
within IfcMaterialProfileSetUsage by means of a cardinal point reference.
This can be used redundant to geometric data in order to convey design intent.
Use in shape models
Profile definitions are used within the geometry and geometric model
resource to create either swept surfaces, swept area solids, or
sectioned spines.
The purpose of the profile
definition within the swept surfaces or swept area solids is to define
a uniform cross section being swept:
- along a line (extrusion) using IfcSurfaceOfLinearExtrusion or IfcExtrudedAreaSolid
- along a circular arc (revolution) using IfcSurfaceOfRevolution or IfcRevolvedAreaSolid
- along a directrix lying on a reference surface using IfcSurfaceCurveSweptAreaSolid
The purpose fo the profile
definition within the sectioned spine is to define a varying cross
sections at several positions along a spine curve. The subtype IfcDerivedProfileDef
is particularly suited to provide the consecutive profiles to be based
on transformations of the start profile and thus maintaining the
identity of vertices and edges.
NOTE Subtypes of the IfcProfileDef
contain parameterized profiles (as subtypes of IfcParameterizedProfileDef)
which establish their own 2D position coordinate system, profiles given
by explicit curve geometry (either open or closed profiles) and two
special types for composite profiles and derived profiles, based on a
2D Cartesian transformation.
An IfcProfileDef
is treated as bounded area if it is used within swept area solids. In
this case, the inside of the profile is part of the profile. The
attribute ProfileType is set to AREA. An IfcProfileDef
is treated as a curve if it is used within swept surfaces. In this
case, the inside of the profile (if the curve is closed) is not part of
the profile. The attribute ProfileType
is set to CURVE.
Figure 320 illustrates use of parameterized profiles within a swept area solid.
![]()
|
Position
The IfcProfileDef is defined within the underlying
coordinate system which is defined by the swept surface or swept area solid
that uses the profile definition. It is the xy plane
- of IfcSweptSurface.Position or
- of IfcSweptAreaSolid.Position or
- of each list member of IfcSectionedSpine.CrossSectionPositions.
In the figure to the left, the z axis of the position coordinate system points outwards of the drawing plane.
Note: The subtype IfcParameterizedProfileDef optionally provides an additional 2D position coordinate system relative to the underlying coordinate system of the IfcProfileDef.
|
![]()
|
Sweeping
In the later use of the IfcProfileDef
within the swept surface or swept area solid, e.g. the IfcExtrudedAreaSolid
(here used as an example), the profile boundaries (here based on the 2D
position coordinate system of IfcParameterizedProfileDef)
are placed within the xy plane of the 3D position coordinate system of
the swept surface or swept area solid.
The profile is inserted into the underlying coordinate system either:
- directly in case of using IfcArbitraryClosedProfileDef
and IfcArbitraryOpenProfileDef,
- through an intermediate position coordinate system in case of
using IfcParameterizedProfileDef.
- through an 2D Cartesian transformation operator (applied directly
to the curve position when using arbitrary profile definitions,
or applied to the position coordinate system when using parameterized
profile definitions) in case of using IfcDerivedProfileDef.
- when using IfcCompositeProfileDef the insertion depends on
the subtype of the included sub-profiles.
|
|
Figure 320 — Profile sweeping |
Profile types
Results of the different usage of the ProfileType attribute are demonstrated here. The ProfileType defines whether the inside (the bounded area) is part of the profile definition (Area) or not (Curve). Figure 321 illustrates the resulting area or curve depending on ProfileType.
![]()
ProfileType = AREA
|
![]()
ProfileType = CURVE
|
|
Figure 321 — Profile types |
Profile specification by external reference
If the profile is standardized by a norm or a catalogue, a reference
to this norm or catalogue should be provided by means of HasExternalReference.
This inverse relationship is used to associate an IfcExternalReference (notably
IfcClassificationReference or IfcLibraryReference) with the
profile.
IfcClassificationReference is used to refer to a profile norm (a common standard or
manufacturer's standard). In this case,
- IfcClassificationReference.ItemReference
contains the formal profile designation from the norm.
(On the other hand, IfcProfileDef.ProfileName contains a displayable name which may
not necessarily be the same as the formal designation.)
- IfcClassificationReference.Name carries the short name of the profile norm.
- Optionally, the norm can be further described by
IfcClassificationReference.ReferencedSource.
IfcLibraryReference is used to refer to a library which contains profile
definitions. In this case,
- IfcLibraryReference.ItemReference contains the identifier of the
profile within the library and is meant to be machine-readable (in contrast to
IfcProfileDef.ProfileName which should be human-readable).
- IfcLibraryReference.Location and .Name or .ReferencedLibrary
further describe the library.
If an external reference is provided, sending systems shall ensure that
the shape of the profile definition object agrees with the definitions in the
referenced classification or library.
Direct instances of IfcProfileDef
Usually, only subtypes of IfcProfileDef should be instantiated.
In some special cases, e.g. if the profile object is used for purposes
other than geometric models (e.g. for structural analysis models), it may be
possible to directly instantiate IfcProfileDef and further specify
the profile only by external reference or by profile properties. The latter
are tracked by the inverse attribute HasProperties.
"
5078;IfcArbitraryOpenProfileDef;"
The open profile IfcArbitraryOpenProfileDef defines an arbitrary two-dimensional open profile for the use within the swept surface geometry. It is given by an open boundary from with the surface can be constructed.
HISTORY New entity in IFC2x.
Informal proposition:
- The Curve has to be an open curve.
Figure 308 illustrates the arbitrary open profile definition. The Curve is defined in the underlying coordinate system. The underlying coordinate system is defined by the swept surface that uses the profile definition. It is the xy plane of:
The Curve attribute defines a two dimensional open bounded curve.
![]() |
Figure 308 — Arbitrary open profile |
"
5083;IfcCenterLineProfileDef;"
The profile IfcCenterLineProfileDef defines an arbitrary two-dimensional open, not self intersecting profile for the use within the swept solid geometry. It is given by an area defined by applying a constant thickness to a centerline, generating an area from which the solid can be constructed.
Among else, IfcCenterLineProfileDef is used to model cold-formed
steel or aluminium sections (Sigma, Zeta, Omega, and similar sections
which are not covered by subtypes of IfcParameterizedProfileDef).
However, since IfcCenterLineProfileDef does not provide shape parameters
except for the thickness, there is generally a need to further specify the
profile definition by means of
- the name,
- external reference to a document or library,
- profile properties,
or a combination of them. See IfcProfileDef for guidance on external references for profiles.
HISTORY New entity in IFC2x3.
Informal proposition:
- The Curve has to be an open curve.
- The Curve has to be a non-intersecting curve.
Figure 311 illustrates the center line profile definition. The Curve is defined in the underlying coordinate system. The underlying coordinate system is defined by the swept surface that uses the profile definition. It is the xy plane of:
The Curve attribute defines a two dimensional open bounded curve. The Thickness attribute defines a constant thickness along the curve.
![]() |
Figure 311 — Centerline profile |
"
5085;IfcArbitraryClosedProfileDef;"
The closed profile IfcArbitraryClosedProfileDef defines an arbitrary two-dimensional profile for the use within the swept surface geometry, the swept area solid or a sectioned spine. It is given by an outer boundary from which the surface or solid can be constructed.
HISTORY: New entity in IFC 1.5. Entity has been renamed from IfcArbitraryProfileDef in IFC Release 2x.
Informal proposition:
- The OuterCurve has to be a closed curve.
- The OuterCurve shall not intersect.
Figure 307 illustrates the arbitrary closed profile definition. The OuterCurve is defined in the underlying coordinate system. The underlying coordinate system is defined by the swept surface or swept area solid that uses the profile definition. It is the xy plane of either:
- IfcSweptSurface.Position
- IfcSweptAreaSolid.Position
or in case of sectioned spines the xy plane of each list member of IfcSectionedSpine.CrossSectionPositions. The OuterCurve
attribute defines a two dimensional closed bounded curve.
![]() |
Figure 307 — Arbitrary closed profile |
"
5091;IfcArbitraryProfileDefWithVoids;"
The IfcArbitraryProfileDefWithVoids defines an arbitrary closed two-dimensional profile with holes defined for the use for the swept area solid or a sectioned spine. It is given by an outer boundary and inner boundaries from with the solid the can be constructed.
HISTORY New entity in IFC2x.
Informal propositions:
- The outer curve and all inner curves shall be closed curves.
- The outer curve shall enclose all inner curves.
- No inner curve shall intersect with the outer curve or any other inner curve.
- No inner curve may enclose another inner curve.
Figure 309 illustrates the arbitrary closed profile definition with voids. The OuterCurve, defined at the supertype IfcArbitraryClosedProfileDef
and the inner curves are defined in the same underlying coordinate system. The common underlying coordinate system is defined by the swept area solid that uses the profile definition. It is the xy plane of:
- IfcSweptAreaSolid.Position
or in case of sectioned spines the xy plane of each list member of IfcSectionedSpine.CrossSectionPositions. The OuterCurve attribute defines a two dimensional closed bounded curve, the InnerCurves define a set of two dimensional closed bounded curves.
![]() |
Figure 309 — Arbitrary profile with voids |
"
5096;IfcCompositeProfileDef;"
The IfcCompositeProfileDef
defines the profile by composition of other profiles. The composition
is given by a set of at least two other profile definitions. Any
profile definition (except for another composite profile) can be used
to construct the composite.
HISTORY New entity in IFC2x.
Figure 314 illustrates the composite profile definition. The IfcCompositeProfileDef does not define an own position coordinate system, it is directly defined in the underlying coordinate system. The underlying coordinate system is defined by the swept surface or swept area solid that uses the profile definition. It is the xy plane of either:
- IfcSweptSurface.Position
- IfcSweptAreaSolid.Position
Or in case of sectioned spines it is the xy plane of each list member of IfcSectionedSpine.CrossSectionPositions. The IfcCompositeProfileDef is defined using other profile definitions. Those other profile definitions are directly inserted into the underlying coordinate system.
- In case of parameterized profile definitions, the Position attribute of those standard profiles is used to place the profiles relatively to each other.
- In case of arbitrary profile definitions, each Cartesian coordinate is given directly within the underlying coordinate system.
NOTE The black coordinate axes show the underlying coordinate system of the swept surface or swept area solid.
![]() |
Figure 314 |
Twin profiles special case
If twin profiles are modeled by profile composition, the base profile should
only be specified once. It is then included into the composite profile directly
and additionally indirectly via IfcMirroredProfileDef. For example, a
double angle made of two L100x10 with 10mm air gap between them, i.e. a
_| |_ shape, can be modeled as
single_L : IfcLShapeProfileDef := IfcLShapeProfileDef(AREA, 'L100X100X10',
IfcAxis2Placement2D(IfcCartesianPoint(((.100+.010)/2., .0)), ?),
.100, .100, .010, .012, ?, 0., ?, ?);
double_L : IfcCompositeProfileDef := IfcCompositeProfileDef(AREA, 'double angle',
(single_L, IfcMirroredProfileDef(AREA, ?, single_L, ?)), 'twin profile');
"
5101;IfcDerivedProfileDef;"
IfcDerivedProfileDef defines the profile by transformation from the parent profile. The transformation is given by a two dimensional transformation operator. Transformation includes translation, rotation, mirror and scaling. The latter can be uniform or non uniform. The derived profiles may be used to define swept surfaces, swept area solids or sectioned spines.
The transformation effects the position, rotation, mirroring or scale of the profile at the underlying coordinate system, i.e. the coordinate system defined by the swept surface or swept area solid that uses the profile definition. It is the xy plane of either:
- IfcSweptSurface.Position
- IfcSweptAreaSolid.Position
or in case of sectioned spines the xy plane of each list member of IfcSectionedSpine.CrossSectionPositions. The position and potential rotation of the ParentProfile within the underlying coordinate system is taken into consideration before applying the Cartesian transformation operator.
Note, if only mirroring is required, IfcMirroredProfileDef should be used instead.
HISTORY: New entity in IFC Release 2x.
Figure 316 illustrates examples of derived profiles.
![]()
|
Parameter
The IfcDerivedProfileDef
is defined using the IfcCartesianTransformationOperator2D
(CTO), which is applied to the parent profile definition.
Example
The example shows an uniform scaling and a transformation
of an IfcRectangleProfileDef
to match the lower-left cardinal point. The attributes of the CTO are:
Axis1 = NIL (defaults to 1.,0.)
Axis2 = NIL (defaults to 0.,1.)
LocalOrigin = IfcCartesianPoint(<1/2 XDim>,<1/2 YDim>)
Scale = 2.
Note: The ParentProfile has a Position
= IfcCartesianPoint(<1/2 XDim>,<1/2 YDim>) already.
|
![]()
|
Parameter
The IfcDerivedProfileDef is defined using
non uniform transformationsby applying the IfcCartesianTransformationOperator2DnonUniform
as a subtype of the 2D CTO.
Example
The example shows a non-uniform scaling and a translation of an IfcRectangleProfileDef
to match the lower-left cardinal point. The attributes of the CTO are:
Axis1 = NIL (defaults to 1.,0.)
Axis2 = NIL (defaults to 0.,1.)
LocalOrigin = IfcCartesianPoint(0.,<1/2 YDim)
Scale = 1.
Scale2 = 2.
Note: The ParentProfile has a Position
= IfcCartesianPoint(<1/2 XDim>,<1/2 YDim>) already.
|
![]()
|
Parameter
The IfcDerivedProfileDef
is defined using mirroring by applying the IfcCartesianTransformationOperator2D
(CTO) to the parent profile.
Example
The example shows a mirroring of an IfcLShapeProfileDef
to match the centre cardinal point. The attributes of the CTO are:
Axis1 = (-1.,0.)
Axis2 = NIL (defaults to 0.,1.)
LocalOrigin = IfcCartesianPoint(0.,0.)
Scale = NIL (defaults to 1.)
Note: The ParentProfile has a Position = IfcCartesianPoint(0.,0.).
This example is for illustration only.
If the transformation results only in mirroring like shown in the example, then
IfcMirroredProfileDef should be used instead of IfcDerivedProfileDef.
|
Note: The following color map applies:
- black coordinate axes show the
underlying coordinate system of the swept surface, swept area solid, or
sectioned spine
- red coordinate axes
show the position coordinate system of the parent profile
- brown coordinate axes
show the position coordinate system of the derived profile
|
|
Figure 316 — Derived profile |
"
5107;IfcMirroredProfileDef;"
The IfcMirroredProfileDef defines the profile by mirroring the parent profile about the y axis of the parent profile coordinate system. That is, left and right of the parent profile are swapped.
Notes:
IfcMirroredProfileDef is primarily useful together with
IfcCShapeProfileDef, IfcLShapeProfileDef,
IfcUShapeProfileDef, or IfcZShapeProfileDef as
parent profile but can be used with other parent profile types as well.
Mirroring of an IfcParameterizedProfileDef is performed after
translation and rotation according to its Position attribute.
For example, if the parent profile's Position offsets it by half
of its width to the right, then the mirrored profile will be offset by
half of its width to the left.
Mirroring about the x axis, i.e. swapping top and bottom, can be
achieved by mirroring about the y axis coupled with 180 degree rotation
about the z axis.
In general, rotation happens in a containing object such as
IfcSweptAreaSolid, i.e. after mirroring by IfcMirroredProfileDef
was performed.
If the parent profile is an IfcParameterizedProfileDef, rotation
can alternatively happen already in the parent profile by means of its
Position attribute, i.e. before mirroring by IfcMirroredProfileDef
was performed.
HISTORY New entity in IFC2x4.
"
5112;IfcProfileProperties;"
This is a collection of properties applicable to section profile definitions.
The following sets of extended profile property definitions are part of this IFC release:
HISTORY New entity in IFC2x2.
IFC2x4 CHANGE Entity made non-abstract. Subtypes IfcGeneralProfileProperties, IfcStructuralProfileProperties, and IfcStructuralSteelProfileProperties deleted. Attribute ProfileName deleted, use ProfileDefinition.ProfileName instead. Attribute ProfileDefinition made mandatory. Attributes Name, Description, and HasProperties added.
"
5117;IfcIShapeProfileDef;"
IfcIShapeProfileDef
defines a section profile that provides the defining parameters of a
symmetrical 'I' section to be used by the swept surface geometry or the
swept area solid. The I-shape profile has values for its overall depth,
width and its web and flange thickness. Additionally a fillet radius
may be given. It represents a I-section that is symmetrical about its
major and minor axes; and that has both top and bottom flanges being
equal and centred on the web.
IfcIShapeProfileDef can also be used to model I sections with
sloped or rounded flanges. The slope and radius cannot be expressed in
explicit attributes, but they may be retrieved by reference to an
external document or library. See IfcProfileDef for guidance on
external references for profile definitions.
HISTORY New entity in IFC2x.
IFC2x4 CHANGE Type of FilletRadius relaxed to allow for zero radius.
Figure 318 illustrates parameters of the I-shape profile definition.
![]() |
Position
The parameterized
profile defines its own position coordinate system.
The underlying
coordinate system is defined by the swept area solid
that uses the profile definition. It is the xy plane of:
- IfcSweptAreaSolid.Position
by using offsets of the position location, the parameterized profile
can be positioned centric (using x,y offsets = 0.), or at any position
relative to the profile. Explicit coordinate offsets are used to define
cardinal points (e.g. upper-left bound).
Parameter
The parameterized profile
is defined by a set of parameter attributes, see attribute definition
below.
|
![]()
Note:
The black coordinate axes show the
underlying coordinate system of the swept surface or swept area solid |
Position
The profile is inserted into the underlying
coordinate system of the swept area solid by using the Position
attribute. In this example (cardinal point of lower left corner) the
attribute values of IfcAxis2Placement2D
are:
Location
= IfcCartesianPoint(<1/2
OverallWidth>,<1/2 OverallDepth>)
RefDirection = NIL (defaults to 1.,0.)
Parameter
If the FilletRadius
is given, it is equally applied to all four corners created by the web
and flanges.
|
|
Figure 318 — I-shape profile |
"
5127;IfcAsymmetricIShapeProfileDef;"
IfcAsymmetricIShapeProfileDef
defines a section profile that provides the defining parameters of a
singly symmetric I-shaped section. Its parameters and orientation relative to the
position coordinate system are according to the following illustration.
The centre of the position coordinate system is in the profile's centre
of the bounding box.
The inherited attributes are redefined as:
- OverallWidth -- BottomFlangeWidth
- FlangeThickness -- BottomFlangeThickness
- FilletRadius -- BottomFlangeFilletRadius
The overall width of the profile is implicitly given by the maximum of
the bottom flange width and the top flange width.
IfcAsymmetricIShapeProfileDef can also be used to model rail profiles
if the application scenario does not require a full explicit shape model of the
rail profile. Alternatively, IfcArbitraryClosedProfileDef can be
used to provide the exact shape of rail profiles. Either way, a reference
to an external document or library should be provided to further define the
profile as described at IfcProfileDef.
HISTORY New entity in Release IFC2x Edition 2.
IFC2x3 CHANGE All profile origins are now in the center of the bounding box. The attribute CentreOfGravityInY has been made OPTIONAL.
IFC2x4 CHANGE Bottom flange is not necessarily wider than top flange. TopFlangeThickness changed from OPTIONAL to mandatory. Type of TopFlangeFilletRadius relaxed to allow for zero radius. Trailing attribute CentreOfGravityInY deleted, use respective property in IfcExtendedProfileProperties instead.
Figure 310 illustrates parameters of the asymmetric I-shaped section definition. The parameterized profile defines its own position coordinate system. The underlying coordinate system is defined by the swept area solid that uses the profile definition. It is the xy plane of:
- IfcSweptAreaSolid.Position
By using offsets of the position location, the parameterized profile can be positioned centric (using x,y offsets = 0.), or at any position
relative to the profile. The parameterized profile is defined by a set of parameter attributes. In the illustrated example, the 'CentreOfGravityInY' property in IfcExtendedProfileProperties, if provided, is negative.
![]() |
Figure 310 — Assymetric I-shape profile |
"
5131;IfcLShapeProfileDef;"
IfcLShapeProfileDef
defines a section profile that provides the defining parameters of an
L-shaped section (equilateral L profiles are also covered by this
entity) to be used by the swept area
solid. Its parameters and orientation relative to the position
coordinate system are according to the following illustration. The
shorter leg has the same direction as the positive Position.P[1]-axis, the longer
or equal leg the same as the positive Position.P[2]-axis. The centre of the
position coordinate system is in the profiles centre
of the bounding box.
HISTORY New entity in IFC2x2.
IFC2x3 CHANGE All profile origins are now in the center of the bounding box.
IFC2x4 CHANGE Width changed from OPTIONAL to mandatory. The previously informal rule that the longer leg is the Depth has been formalized. Types of FilletRadius and EdgeRadius were relaxed to allow for zero values. Trailing attributes CentreOfGravityInX and CentreOfGravityInY deleted, use respective properties in IfcExtendedProfileProperties instead. WHERE rule which required Width <= Depth removed.
Figure 319 illustrates parameters of equal-sided and non-equal sided L-shaped section definitions.
![]()
|
Position
The parameterized profile defines its own position coordinate system.
The underlying coordinate system is defined by the swept area solid
that uses the profile definition. It is the xy plane of:
- IfcSweptAreaSolid.Position
by using offsets of the position location, the parameterized profile
can be positioned centric (using x,y offsets = 0.), or at any position
relative to the profile.
In the illustrated example, the 'CentreOfGravityInX' and 'CentreOfGravityInY' properties in IfcExtendedProfileProperties, if provided, are both negative.
|
![]()
Note:
The black coordinate axes show the
underlying coordinate system of the swept surface or swept area solid
|
Position
The profile is inserted into the underlying
coordinate system of the swept area solid by using the Position
attribute. In this example (cardinal point of gravity) the
attribute values of IfcAxis2Placement2D
are:
Location = IfcCartesianPoint(
+|CentreOfGravityInX|,
+|CentreOfGravityInY|)
RefDirection = NIL (defaults to 1.,0.)
In the illustrated example, the x and y value of Position.Location, i.e. the measures |CentreOfGravityInX| and |CentreOfGravityInY| are both positive. On the other hand, the properties named 'CentreOfGravityInX' and 'CentreOfGravityInY' in IfcExtendedProfileProperties, if provided, must both be set to 0 now because the centre of gravity of the resulting profile definition is located in the coordinate origin.
|
|
Figure 319 — L-shape profile |
"
5139;IfcUShapeProfileDef;"
IfcUShapeProfileDef defines
a section profile that provides the defining parameters of a U-shape
(channel) section to be used by the swept area solid. Its parameters
and orientation relative to the position coordinate system are
according to the following illustration. The centre of the position
coordinate system is in the profile's centre of the bounding box.
HISTORY New entity in IFC2x2.
IFC2x3 CHANGE All profile origins are now in the center of the bounding box.
IFC2x4 CHANGE Type of FilletRadius and EdgeRadius relaxed to allow for zero radius.
Trailing attribute CentreOfGravityInX deleted, use respective property in IfcExtendedProfileProperties instead.
Figure 327 illustrates parameters of the U-shape profile definition.
![]()
|
Position
The parameterized profile defines its own position coordinate system.
The underlying coordinate system is defined by the swept area solid
that uses the profile definition. It is the xy plane of:
- IfcSweptAreaSolid.Position
By using offsets of the position location, the parameterized profile
can be positioned centric (using x,y offsets = 0.), or at any position
relative to the profile.
|
|
Figure 327 — U-shape profile |
"
5149;IfcCShapeProfileDef;"
IfcCShapeProfileDef defines
a section profile that provides the defining parameters of a C-shaped
section to be used by the swept area solid. This section is typically
produced by cold forming steel. Its parameters and orientation relative
to the position coordinate system are according to the following
illustration. The centre of the position coordinate system is in the
profile's centre of the bounding box.
HISTORY New entity in IFC2x2.
IFC2x3 CHANGE All profile origins are now in the center of the bounding box.
IFC2x4 CHANGE Type of InternalFilletRadius relaxed to allow for zero radius.
Trailing attribute CentreOfGravityInX deleted, use respective property in IfcExtendedProfileProperties instead.
Figure 315 illustrates parameters of the C-shape profile definition. The parameterized profile defines its own position coordinate system. The underlying coordinate system is defined by the swept area solid that uses the profile definition. It is the xy plane of:
- IfcSweptAreaSolid.Position
By using offsets of the position location, the parameterized profile can be positioned centric (using x,y offsets = 0.), or at any position relative to the profile. The parameterized profile is defined by a set of parameter attributes. In the illustrated example, the 'CentreOfGravityInX' property in IfcExtendedProfileProperties, if provided, is negative.
![]() |
Figure 315 — C-shape profile |
"
5158;IfcZShapeProfileDef;"
IfcZShapeProfileDef defines
a section profile that provides the defining parameters of a Z-shape
section to be used by the swept area solid. Its parameters and
orientation relative to the position coordinate system are according to
the following illustration. The centre of the position coordinate
system is in the profile's centre of the bounding box.
HISTORY New entity in IFC2x2.
IFC2x Edition 4 CHANGE Type of FilletRadius and EdgeRadius relaxed to allow for zero radius.
Figure 328 illustrates parameters of the Z-shape profile definition.
![]()
|
Position
The parameterized profile defines its own position coordinate system.
The underlying coordinate system is defined by the swept area solid
that uses the profile definition. It is the xy plane of:
- IfcSweptAreaSolid.Position
By using offsets of the position location, the parameterized profile
can be positioned centric (using x,y offsets = 0.), or at any position
relative to the profile.
|
|
Figure 328 — Z-shape profile |
"
5166;IfcTShapeProfileDef;"
IfcTShapeProfileDef defines
a section profile that provides the defining parameters of a T-shaped
section to be used by the swept area solid. Its parameters and
orientation relative to the position coordinate system are according to
the following illustration. The centre of the position coordinate
system is in the profile's centre of the bounding box.
HISTORY New entity in IFC2x2.
IFC2x3 CHANGE All profile origins are now in the center of the bounding box.
IFC2x4 CHANGE Type of FilletRadius, FlangeEdgeRadius, and WebEdgeRadius relaxed to allow for zero radius. Trailing attribute CentreOfGravityInY deleted, use respective property in IfcExtendedProfileProperties instead.
Figure 326 illustrates parameters of the T-shape profile definition.
![]()
|
Position
The parameterized profile defines its own position coordinate system.
The underlying
coordinate system is defined by the swept area solid
that uses the profile definition. It is the xy plane of:
- IfcSweptAreaSolid.Position
by using offsets of the position location, the parameterized profile
can be positioned centric (using x,y offsets = 0.), or at any position
relative to the profile.
|
|
Figure 326 — T-shape profile |
"
5178;IfcCircleProfileDef;"
IfcCircleProfileDef defines a circle as the profile definition used by the swept surface geometry or by the swept area solid. It is given by its Radius attribute and placed within the 2D position coordinate system, established by the Position attribute.
HISTORY New class in IFC 1.5.
Figure 313 illustrates parameters for the circle profile definition. The parameterized profile defines its own position coordinate system. The underlying coordinate system is defined by the swept surface or swept area solid that uses the profile definition. It is the xy plane of either:
- IfcSweptSurface.Position
- IfcSweptAreaSolid.Position
Or in case of sectioned spines, it is the xy plane of each list member of IfcSectionedSpine.CrossSectionPositions. By using offsets of the position location, the parameterized profile can be positioned centric (using x,y offsets = 0.), or at any position relative to the profile. Explicit coordinate offsets are used to define cardinal points (e.g. upper-left bound). The Position attribute defines the 2D position coordinate system of the circle.
The Radius attribute defines the radius of the circle.
![]() |
Figure 313 — Circle profile |
"
5181;IfcCircleHollowProfileDef;"
IfcCircleHollowProfileDef
defines a section profile that provides the defining parameters of a
circular hollow section (tube) to be used by the swept area solid. Its
parameters and orientation relative to the
position coordinate system are according to the following
illustration.The centre of the position coordinate system is in the
profile's centre of the bounding box (for symmetric profiles identical
with the centre of gravity).
HISTORY New entity in IFC2x2.
Figure 312 illustrates parameters of the circular hollow profile definition. The parameterized profile defines its own position coordinate system. The underlying coordinate system is defined by the swept area solid that uses the profile definition. It is the xy plane of:
- IfcSweptAreaSolid.Position
By using offsets of the position location, the parameterized profile can be positioned centric (using x,y offsets = 0.), or at any position relative to the profile. Explicit coordinate offsets are used to define cardinal points (for example, upper-left bound). The parameterized profile is defined by a set of parameter attributes.
![]() |
Figure 312 — Circle hollow profile |
"
5184;IfcEllipseProfileDef;"
IfcEllipseProfileDef defines an ellipse as the profile definition used by the swept surface geometry
or the swept area solid. It is given by its semi axis attributes and placed within the 2D position coordinate system, established by the Position attribute.
HISTORY New entity in IFC2x
Figure 317 illustrates parameters for the ellipse profile definition. The parameterized profile defines its own position coordinate system.
The underlying coordinate system is defined by the swept surface or swept area solid that uses the profile definition. It is the xy plane of either:
- IfcSweptSurface.Position
- IfcSweptAreaSolid.Position
Or in case of sectioned spines it is the xy plane of each list member of IfcSectionedSpine.CrossSectionPositions. By using offsets of the position location, the parameterized profile can be positioned centric (using x,y offsets = 0.), or at any position relative to the profile. Explicit coordinate offsets are used to define cardinal points (for example, upper-left bound). The location of the position coordinate system defines the center of the ellipse. The SemiAxis1 attribute defines the first radius of the ellipse in the direction of the X axis, the SemiAxis2 attribute defines the second radius of the ellipse in the direction of the Y axis.
NOTE The semi axes of the ellipse are rectangular to each other by definition.
![]() |
Figure 317 — Ellipse profile |
"
5187;IfcRectangleProfileDef;"
IfcRectangleProfileDef defines a rectangle as the profile definition used by the swept surface geometry or the swept area solid. It is given by its X extent and its Y extent, and placed within the 2D position coordinate system, established by the Position attribute. It is placed centric within the position coordinate system.
HISTORY: New class in IFC 1.5. The use definition has changed in IFC Release 2x.
Figure 323 illustrates parameters of the rectangle profile definition.
![]() |
Position
The parameterized profile defines its own position coordinate system.
The underlying
coordinate system is defined by the swept surface or swept area solid
that uses the profile definition. It is the xy plane of either:
- IfcSweptSurface.Position
- IfcSweptAreaSolid.Position
or in case of sectioned spines the xy plane of each list member of IfcSectionedSpine.CrossSectionPositions.
By using offsets of the position location, the parameterized profile
can be positioned centric (using x,y offsets = 0.), or at any position
relative to the profile. Explicit coordinate offsets are used to define
cardinal points (for example, upper-left bound).
Parameter
The IfcRectangleProfileDef
is defined within the position
coordinate system, where the XDim
defines the length measure
for the length of the rectangle (half along the positive x-axis) and
the YDim
defines the length measure for the width of the
rectangle (half along the positive y-axis).
|
|
Figure 323 — Rectangle profile |
"
5192;IfcRectangleHollowProfileDef;"
IfcRectangleHollowProfileDef defines a section profile that provides the defining parameters of a rectangular (or square) hollow section to be used by the swept surface geometry or the swept area solid. Its parameters and orientation relative to the position coordinate system are according to the following illustration. A square hollow section can be defined by equal values for h and b. The centre of the position coordinate system is in the profiles centre of the bounding box (for symmetric profiles identical with the centre of gravity). Normally, the longer sides are parallel to the y-axis, the shorter sides parallel to the x-axis.
HISTORY New entity in IFC2x2.
IFC2x4 CHANGE Types of InnerFilletRadius and OuterFilletRadius relaxed to allow for zero values.
Figure 322 illustrates parameters of a rectangular or square hollow profile definition.
![]()
|
Position
The parameterized profile defines its own position coordinate system.
The underlying coordinate system is defined by the swept area solid
that uses the profile definition. It is the xy plane of:
- IfcSweptAreaSolid.Position
by using offsets of the position location, the parameterized profile
can be positioned centric (using x,y offsets = 0.), or at any position
relative to the profile.
|
|
Figure 322 — Rectangle hollow profile |
"
5199;IfcRoundedRectangleProfileDef;"
IfcRoundedRectangleProfileDef defines a rectangle with equally rounded corners as the profile definition used by the swept surface geometry or the swept area solid. It is given by the X extent, the Y extent, and the radius for the rounded corners, and placed within the 2D position coordinate system, established by the Position attribute. It is placed centric within the position coordinate system, that is, in the center of the bounding box.
HISTORY New class in IFC2x.
IFC2x PLATFORM CHANGE The IfcRoundedRectangleProfileDef is now subtyped from IfcRectangleProfileDef. The XDim and YDim attributes have been removed (now inherited from supertype).
Figure 324 illustrates parameters of the rounded rectangle profile definition.
![]() |
Position
The parameterized profile defines its own position coordinate system.
The underlying
coordinate system is defined by the swept surface or swept area solid
that uses the profile definition. It is the xy plane of either:
- IfcSweptSurface.Position
- IfcSweptAreaSolid.Position
or in case of sectioned spines the xy plane of each list member of IfcSectionedSpine.CrossSectionPositions.
By using offsets of the position location, the parameterized profile
can be positioned centric (using x,y offsets = 0.), or at any position
relative to the profile. Explicit coordinate offsets are used to define
cardinal points (e.g. upper-left bound).
Parameter
The IfcRoundedRectangleProfileDef
is defined within the
position coordinate system, where the XDim
defines the measure
for the length of the rectangle (half along the positive x-axis), the YDim
defines the length measure for the width of the rectangle (half along
the positive y-axis) and the RoundingRadius
defines the radius
of curvature in all four corners of the rectangle.
|
|
Figure 324 — Rounded rectangle profile |
"
5202;IfcTrapeziumProfileDef;"
IfcTrapeziumProfileDef defines a trapezium as the profile definition used by the swept surface geometry or the swept area solid. It is given by its Top X and Bottom X extent and its Y extent as well as by the offset of the Top X extend, and placed within the 2D position coordinate system, established by the Position attribute. It is placed centric within the position coordinate system, that is, in the center of the bounding box.
HISTORY New class in IFC 1.5. The use definition has changed in IFC2x.
Figure 325 illustrates parameters of the trapezium profile definition.
![]() |
Position
The parameterized profile defines its own position coordinate system.
The underlying
coordinate system is defined by the swept surface or swept area solid
that uses the profile definition. It is the xy plane of either:
- IfcSweptSurface.Position
- IfcSweptAreaSolid.Position
or in case of sectioned spines the xy plane of each list member of IfcSectionedSpine.CrossSectionPositions.
By using offsets of the position location, the parameterized profile
can be positioned centric (using x,y offsets = 0.), or at any position
relative to the profile. Explicit coordinate offsets are used to define
cardinal points (e.g. upper-left bound).
Parameter
The IfcTrapeziumProfileDef
is defined within the position
coordinate system, where the BottomDim
defines the length
measure for the bottom line (half along the positive x-axis) and the YDim
defines the length measure for the parallel distance of bottom and top
line (half along the positive y-axis). The top line starts with a
distance of TopXOffset
from [-BottomLine/2,YDim] (which can be
negative, zero, or positive) and has a length of TopXDim
along
the positive x-axis.
|
|
Figure 325 — Trapezium profile |
"
5207;IfcReinforcementBarProperties;"
IfcReinforcementProperties defines the set of properties for a specific combination of reinforcement bar steel grade, bar type and effective depth.
HISTORY New entity in IFC2x2.
The total cross section area for the specific steel grade is always provided. Additionally also general reinforcing bar configurations as a count of bars may be provided as defined in attribute BarCount. In this case the nominal bar diameter should be identical for all given bars as defined in attribute NominalBarDiameter.
"
5217;IfcSectionProperties;"
IfcSectionProperties defines the cross section properties for a single longitudinal piece of a cross section. It is a special-purpose helper class for IfcSectionReinforcementProperties.
HISTORY New entity in IFC2x2.
The section piece may be either uniform or tapered. In the latter case an end profile should also be provided. The start and end profiles are assumed to be of the same profile type. Generally only rectangular or circular cross section profiles are assumed to be used.
"
5224;IfcSectionReinforcementProperties;"
IfcSectionReinforcementProperties defines the cross section properties of reinforcement for a single longitudinal piece of a cross section with a specific reinforcement usage type.
HISTORY New entity in IFC2x2.
Several sets of cross section reinforcement properties represented by instances of IfcReinforcementProperties may be attached to the section reinforcement properties
(IfcReinforcementDefinitionProperties of IfcStructuralElementsDomain schema),
one for each combination of steel grades and reinforcement bar types and sizes.
"
5243;IfcApplication;"
IfcApplication holds the information about an IFC compliant application developed by an application developer. The IfcApplication utilizes a short identifying name as provided by the application developer.
HISTORY New entity in IFC R1.5.
"
5253;IfcOwnerHistory;"
IfcOwnerHistory defines all history and identification related information. In order to provide fast access it is directly attached to all independent objects, relationships and properties.
IfcOwnerHistory is used to identify the creating and owning application and user for the associated object, as well as capture the last modifying application and user.
HISTORY New entity in IFC R1.0. Modified in IFC R2x4.
Informal propositions
- If LastModifiedDate is defined but ChangeAction is not asserted, then the state of ChangeAction is assumed to be UNDEFINED.
- If both LastModifiedDate and ChangeAction are asserted, then the state of ChangeAction applies to the value asserted in LastModifiedDate.
"
5275;IfcTable;"
An IfcTable is a data structure for the provision of information in the form of rows and columns. Each instance may have IfcTableColumn instances that define the name, description and units for each column. The rows of information are stored as a list of IfcTableRow objects.
Limitation: For backwards compatibility, the rows of an IfcTable object are constrained to have the same number of cells. The first Row of the table provides the number of cells. All other rows are forced to include the same number of cells. This is enforced by the WR2.
Figure 335 illustrates table use.
![]() |
Figure 335 — Table use |
Figure 336 depicts how tables were structured prior to IFC2x4.
![]() |
Figure 336 — Table use alternative |
HISTORY New entity in IFC R1.5.
IFC2x4 CHANGE Columns attribute added.
"
5284;IfcTableRow;"
IfcTableRow contains data for a single row within an IfcTable.
Limitation: For backward compatibility, all IfcTableRow objects referenced by an IfcTable shall have the same number of Row Cells. The actual number of Cells shall be taken from the number of cells of the first IfcTableRow for that table. The number of Cells is calculated by the derived attribute NumberOfCellsInRow in the associated IfcTable.
Figure 337 illustrates table row use.
![]() |
Figure 337 — Table row use |
Figure 338 depicts how table rows were structured prior to IFC2x4 with the use of the IsHeading flag. Note that the use of the IfcTableColumn constructs should be used instead of the IsHeading flag (which remains for backward compatibility only):
![]() |
Figure 338 — Table row use alternative |
HISTORY New entity in IFC R1.5.
"
5288;IfcTableColumn;"
An IfcTableColumn is a data structure that captures column information for use in an IfcTable. Each instance defines the name, description, identifier, and units of measure that are applicable to the columnar data associated with the IfcTableRow objects.
The use of IfcTableColumn supercedes the IsHeading flag associated with IfcTableRow.
HISTORY New entity in IFC2x4.
"
5295;IfcBooleanResult;"
Definition from ISO/CD 10303-42:1992: A Boolean result
is the result of a regularized operation on two solids to create
a new solid. Valid operations are regularized union, regularized
intersection, and regularized difference. For purpose of Boolean
operations, a solid is considered to be a regularized set of
points. The final Boolean result depends upon the operation and
the two operands. In the case of the difference operator the
order of the operands is also significant. The operator can be
either union, intersection or difference. The effect of these
operators is described below:
- Union on two solids is the new solid that is the
regularization of the set of all points that are in either the
first operand or the second operand or in both.
- Intersection on two solids is the new solid that is the
regularization of the set of all points that are in both the
first operand and the second operand.
- The result of the difference operation on two solids is the
regularization of the set of all points which are in the first
operand, but not in the second operand.
NOTE For example if the first operand is a block and the second operand is a solid cylinder of suitable dimensions and location, the boolean result produced with the difference operator would be a block with a circular hole.
NOTE Corresponding ISO 10303-42 entity: boolean_result. The derived attribute Dim has been added at this level and was therefore demoted from the geometric_representation_item. Please refer to ISO/IS 10303-42:1994, p.175 for the final definition of the formal standard.
HISTORY: New class in IFC Release 1.5.1.
"
5304;IfcHalfSpaceSolid;"
Definition from ISO/CD 10303-42:1992: A half space solid is defined by the half space which is the regular subset of the domain which lies on one side of an unbounded surface. The side of the surface which is in the half space is determined by the surface normal and the agreement flag. If the agreement flag is TRUE, then the subset is the one the normal points away from. If the agreement flag is FALSE, then the subset is the one the normal points into. For a valid half space solid the surface shall divide the domain into exactly two subsets. Also, within the domain the surface shall be manifold and all surface normals shall point into the same subset.
NOTE A half space is not a subtype of solid model (IfcSolidModel), half space solids are only useful as operands in Boolean expressions.
NOTE Corresponding STEP entity: half_space_solid. Please refer to ISO/IS 10303-42:1994, p. 185 for the final definition of the formal standard. The derived attribute Dim has been added at this level and was therefore demoted from the geometric_representation_item.
HISTORY New class in IFC Release 1.5
Informal propositions:
- The base surface shall divide the domain into exactly two subsets. If the half space solid is of subtype boxed half space (IfcBoxedHalfSpace), the domain in question is that of the attribute enclosure. In all other cases the domain is all of space and the base surface shall be unbounded.
- The base surface shall be an unbounded surface (subtype of IfcElementarySurface).
Figure 258 illustrates the definition of the IfcHalfSpaceSolid within a given coordinate system. The base surface is given by an unbounded plane, the red boundary is shown for visualization purposes only.
![]() |
Figure 258 — Half space solid geometry |
"
5310;IfcBoxedHalfSpace;"
Definition from ISO/CD 10303-42:1992: This entity is a subtype of the half space solid which is trimmed by a surrounding rectangular box. The box has its edges parallel to the coordinate axes of the geometric coordinate system.
NOTE The purpose of the box is to facilitate CSG computations by producing a solid of finite size.
The IfcBoxedHalfSpace is
used (as its supertype IfcHalfSpaceSolid) only within
Boolean operations. It divides the domain into exactly two
subsets, where the domain in question is that of the attribute
Enclosure.
The purpose of the attribute Enclosure is to provide a
search box for the other operand in the Boolean operation. It
shall be sufficiently large to fully enclose the resulting solid
after the Boolean operation with the half space. It however does
not alter the final result. The result of the Boolean operation
would be the same, as if executed by the supertype
IfcHalfSpaceSolid. See Figure 253 below.
![]() |
Figure 253 — Boxed half space operands |
NOTE Corresponding ISO 10303-42 entity: boxed_half_space, please refer to ISO/IS 10303-42:1994, p. 185 for the final definition of the formal standard. The IFC class IfcBoundingBox is used for the definition of the enclosure, providing the same definition as box_domain.
HISTORY New entity in IFC Release 1.5.1, improved documentation available in IFC Release 2x.
IFC2x4 CHANGE Usage correct, position coordinate system for Enclosure is the object coordinate system.
The IfcBoundingBox (relating to ISO 10303-42:1994 box_domain) that provides the enclosure is given for the convenience of the receiving application to enable the use of size box comparison for efficiency (for example, to check first whether size boxes intersect, if not no calculations has to be done to check whether the solids of the entities intersect).
The Enclosure therefore helps to prevent dealing with infinite-size related issues. The enclosure box is positioned within the object coordinate system, established by the ObjectPlacement of the element represented (for example, by IfcLocalPlacement). Figure 254 shows the Enclosure box being sufficiently large to fully enclose the Boolean result.
![]() |
Figure 254 — Boxed half space geometry |
"
5313;IfcBoundingBox;"
Definition from ISO/CD 10303-42:1992: A box domain
is an orthogonal box parallel to the axes of the geometric
coordinate system which may be used to limit the domain of
a half space solid. A box domain is specified by the
coordinates of the bottom left corner, and the lengths of
the sides measured in the directions of the coordinate
axes.
Every semantic object having a
physical extent might have a minimum default representation
of a bounding box. The bounding box is therefore also used
as minimal geometric representation for any geometrically
represented object. Therefore the IfcBoundingBox is
subtyped from IfcGeometricRepresentationItem.
NOTE Corresponding ISO 10303-42 entity: box_domain, please refer to ISO/IS 10303-42:1994, p. 186 for the final definition of the formal standard. In IFC the bounding box can also be used outside of the context of an IfcBoxedHalfSpace.
HISTORY New entity in IFC Release 1.0.
As shown in Figure 252, the IfcBoundingBox is defined with its own location which can be used to place the IfcBoundingBox relative to the geometric coordinate system. The IfcBoundingBox is defined by the lower left corner (Corner) and the upper right corner (XDim, YDim, ZDim measured within the parent co-ordinate system).
![]() |
Figure 252 — Bounding box |
"
5319;IfcPolygonalBoundedHalfSpace;"
The polygonal bounded
half space is a special subtype of a half space solid, where the
material of the half space used in Boolean expressions is bounded by a
polygonal boundary. The base
surface of the half space is positioned by its normal relativeto the
object coordinate system
(as defined at the supertype IfcHalfSpaceSolid), and
its polygonal (with or without arc segments) boundary is defined in the
XY plane of the position
coordinate system established by the Position
attribute, the subtraction body is extruded perpendicular to the XY
plane of the position coordinate system, that is, into the direction of the
positive Z axis defined by the Position attribute.
The boundary is defined by a 2 dimensional polyline (or 2 dimensional composite curve,
consisting of straight segments and circular arc segments)
within the
XY plane of the position coordinate system. The side of the surface
which is in the half space is determined by the surface normal and the
agreement flag. If the agreement flag is TRUE, then the subset is the
one the normal points away from. If the agreement flag is FALSE, then
the subset is the one the normal points into.
NOTE A polygonal bounded half space is not a subtype of IfcSolidModel, half space solids are only useful as operands in Boolean expressions.
HISTORY New class in IFC Release 2x.
Informal propositions:
- The IfcPolyline or the IfcCompositeCurve
providing the PolygonalBoundary
shall be closed.
- If the PolygonalBoundary
is given by an IfcCompositeCurve, it shall only
have IfcCompositeCurveSegment's of type IfcPolyline,
or IfcTrimmedCurve (having a BasisCurve
of type IfcLine, or IfcCircle)
Figure 259 illustrates a polygonal bounded half space.
- Black coordinates indicate the object coordinate system (usually provided by IfcLocalPlacement).
- Green coordinates indicate the position coordinate system; the PolygonalBoundary is given within this coordinate system. It is provided by IfcPolygonalBoundedHalfSpace.Position. This coordinate system is relative to the object coordinate system. The extrusion direction of the subtraction body is the positive Z axis.
- Red coordinates indicate the normal of the plane. It is provided by the BaseSurface (IfcSurface.Position). This normal is also relative to the object coordinate system.
![]() |
Figure 259 — Polygonal half space geometry |
Purpose
The polygonal bounded half space is used to limit the volume of the
half space in Boolean difference expressions. Only the part that is
defined by a theoretical intersection between the half space solid and
an extruded area solid, defined by extruding the polygonal boundary, is
used for Boolean expressions.
Parameter
The PolygonalBoundary defines the 2D polyline which
bounds the effectiveness of the half space in Boolean expressions. The BaseSurface
is defined by a plane, and the normal of the plane together with the AgreementFlag
defines the side of the material of the half space.
"
5324;IfcSolidModel;"
Definition from ISO/CD 10303-42:1992: A solid model is a complete representation of the nominal shape of a product such that all points in the interior are connected. Any point can be classified as being inside, outside, or on the boundary of a solid. There are several different types of solid model representations.
NOTE: Corresponding ISO 10303-42 entity: solid_model, only three subtypes have been incorporated into the current IFC Release - subset of manifold_solid_brep (IfcManifoldSolidBrep, constraint to faceted B-rep), swept_area_solid (IfcSweptAreaSolid), the swept_disk_solid (IfcSweptDiskSolid) and subset of csg_solid (IfcCsgSolid). The derived attribute Dim has been added at this level and was therefore demoted from the geometric_representation_item. Please refer to ISO/IS 10303-42:1994, p. 170 for the final definition of the formal standard.
HISTORY: New entity in IFC Release 1.5
"
5330;IfcManifoldSolidBrep;"
Definition from ISO/CD 10303-42:1992: A manifold solid
B-rep is a finite, arcwise connected volume bounded by one or
more surfaces, each of which is a connected, oriented, finite,
closed 2-manifold. There is no restriction on the genus of the
volume, nor on the number of voids within the volume.
The Boundary Representation (B-rep) of a manifold solid
utilizes a graph of edges and vertices embedded in a connected,
oriented, finite, closed two manifold surface. The embedded graph
divides the surface into arcwise connected areas known as faces.
The edges and vertices, therefore, form the boundaries of the
face and the domain of a face does not include its boundaries.
The embedded graph may be disconnected and may be a pseudo graph.
The graph is labeled; that is, each entity in the graph has a
unique identity. The geometric surface definition used to specify
the geometry of a face shall be 2-manifold embeddable in the
plane within the domain of the face. In other words, it shall be
connected, oriented, finite, non-self-intersecting, and of
surface genus 0.
Faces do not intersect except along their boundaries. Each
edge along the boundary of a face is shared by at most one other
face in the assemblage. The assemblage of edges in the B-rep do
not intersect except at their boundaries (i.e., vertices). The
geometry curve definition used to specify the geometry of an edge
shall be arcwise connected and shall not self intersect or
overlap within the domain of the edge. The geometry of an edge
shall be consistent with the geometry of the faces of which it
forms a partial bound. The geometry used to define a vertex shall
be consistent with the geometry of the faces and edges of which
it forms a partial bound.
A B-rep is represented by one or more closed shells which
shall be disjoint. One shell, the outer, shall completely enclose
all the other shells and no other shell may enclose a shell. The
facility to define a B-rep with one or more internal voids is
provided by a subtype. The following version of the Euler formula
shall be satisfied, where V, E, F, Ll and S are the
numbers of unique vertices, edges, faces, loop uses and shells in
the model and Gs is the sum of the genus of the
shells.
![]()
Instances of type IfcManifoldSolidBrep shall be of type
IfcFacetedBrep, using only IfcPolyLoop for the
bounds of IfcFaceBound, or of type IfcAdvancedBrep,
using only IfcAdvancedFace for the face geometry, and
IfcEdgeCurve for the edges.
NOTE: Corresponding ISO 10303-42 entity: manifold_solid_brep. Please refer to ISO/IS 10303-42:1994, p. 170 for the final definition of the formal standard. IfcManifoldSolidBrep is defined as ABSTRACT supertype to prevent it from direct instantiation.
HISTORY: New entity in IFC Release 1.0
Informal proposition:
- The dimensionality of a manifold solid brep shall be 3.
- The extent of the manifold solid brep shall be finite and
non-zero.
- All elements of the manifold solid brep shall have defined
associated geometry.
- The shell normals shall agree with the B-rep normal and point
away from the solid represented by the B-rep.
- Each face shall be referenced only once by the shells of the
manifold solid brep.
- The Euler equation shall be satisfied for the boundary
representation, where the genus term ""shell term"" us the sum of
the genus values for the shells of the brep.
"
5334;IfcFacetedBrep;"
Definition from ISO/CD 10303-42:1992: A faceted B-rep
is a simple form of boundary representation model in which all
faces are planar and all edges are straight lines. Unlike the
B-rep model, edges and vertices are not represented explicitly in
the model but are implicitly available through the poly loop
entity. A faceted B-rep has to meet the same topological
constraints as the manifold solid B-rep.
NOTE The faceted B-rep has been introduced in order to support the larger number of systems that allow boundary type solid representations with planar surfaces only.
NOTE Corresponding ISO 10303-42 entity: faceted_brep. Please refer to ISO/IS 10303-42:1994, p. 173 for the final definition of the formal standard. In the current IFC Release faceted B-rep with voids is represented by an own subtype and not defined via an implicit ANDOR supertype constraint as in ISO/IS 10303-42:1994. This change has been made due to the fact, that only ONEOF supertype constraint is allowed within the IFC data schema.
HISTORY New entity in IFC Release 1.0
Informal proposition:
- All the bounding loops of all the faces of all the shells in
the IfcFacetedBrep shall be of type
IfcPolyLoop.
- All vertices shall be referenced by all polyloops, sharing the vertex. That is, each Cartesian point shall be referenced by at least three polyloops.
Figure 257 illustrates use of IfcFacetedBrep for boundary representation models with planar surfaces only. The diagram shows the topological and geometric representation items that are used for faceted breps. Each IfcCartesianPoint, used within the IfcFacetedBrep shall be referenced three times by an IfcPolyLoop bounding a different IfcFace.
![]() |
Figure 257 — Faceted B-rep |
"
5336;IfcFacetedBrepWithVoids;"
The IfcFacetedBrepWithVoids
is a specialization of a faceted B-rep which contains one or more
voids in its interior. The voids are represented as closed shells
which are defined so that the shell normal point into the
void.
NOTE˙ Corresponding ISO 10303-42 entity: brep_with_voids (see note above). Please refer to ISO/IS 10303-42:1994, p. 173 for the final definition of the formal standard. In IFC faceted B-rep with voids is represented by this subtype IfcFacetedBrepWithVoids and not defined via an implicit ANDOR supertype constraint as in ISO/IS 10303-42:1994 between an instance of faceted_brep AND brep_with_voids. This change has been made due to the fact, that only ONEOF supertype constraint is allowed within the IFC object model.
HISTORY˙ New entity in IFC Release 1.0
IFC2x4 CHANGE˙ Subtyping changed from IfcManifoldSolidBrep to IfcFacetedBrep with upward compatibility for file based exchange.
Informal propositions:
- Each void shell shall be disjoint from the outer shell and
from every other void shell
- Each void shell shall be enclosed within the outer shell but
not within any other void shell. In particular the outer shell is
not in the set of void shells
- Each shell in the IfcManifoldSolidBrep shall be
referenced only once.
- All the bounding loops of all the faces of all the shells in
the IfcFacetedBrep shall be of type
IfcPolyLoop.
"
5338;IfcAdvancedBrep;"
An advanced B-rep is a boundary
representation model in which all faces, edges and vertices are
explicitly represented. It is a solid with explicit topology and
elementaty or free-form geometry. The faces of the B-rep are of
type IfcAdvancedFace. An advanced B-rep has to meet the
same topological constraints as the manifold solid B-rep.
NOTE The advanced B-rep has been introduced in
order to support the increasing number of applications that can
define and exchange B-rep models based on NURBS or other b-spline
surfaces.
NOTE Corresponding ISO 10303-42 entity: advanced_brep_shape_representation. Please refer to ISO/IS 10303-514:1999 for the final definition of the formal standard. There is no explicit entity in ISO 10303-42 for an advanced B-rep, the advanced_brep_shape_representation only ensures that only such kind of manifold B-rep's are used in a shape representation.
HISTORY New entity in IFC2x4
Informal proposition:
- each face is a face surface;
- each face surface has its geometry defined by an elementary
surface, swept surface or a b-spline surface;
- the edges used to define the boundaries of the face shall all
reference an edge curve
- each curve used to define the geometry of the faces and face
bounds shall be either a conic, or a line or a polyline or a
b-spline curve
- the edges used to define the face boundaries shall all be
trimmed by vertices of type vertex point
- no loop used to define a face bound shall be of the oriented
subtype
Figure 249 illustrates use of IfcAdvancedBrep for boundary representation models with b-spline surfaces. The diagram shows the topological and geometric representation items that are used for advanced B-reps, based on IfcAdvancedFace.
![]() |
Figure 249 — Advanced Brep |
"
5341;IfcAdvancedBrepWithVoids;"
The IfcAdvancedBrepWithVoids is a specialization of an
advanced B-rep which contains one or more voids in its interior.
The voids are represented as closed shells which are defined so
that the shell normal point into the void.
NOTE˙ Corresponding ISO 10303-42 entity: brep_with_voids (see note above). Please refer to ISO/IS 10303-42:1994, p. 173 for the final definition of the formal standard. In IFC advanced B-rep with voids is represented by this subtype IfcAdvancedBrepWithVoids and not defined via an implicit ANDOR supertype constraint as in ISO/IS 10303-42:1994 between an instance of manifold_solid_brep AND brep_with_voids. This change has been made due to the fact, that only ONEOF supertype constraint is allowed within the IFC object model.
HISTORY˙ New entity in IFC2x4
Informal propositions:
- Each void shell shall be disjoint from the outer shell and
from every other void shell
- Each void shell shall be enclosed within the outer shell but
not within any other void shell. In particular the outer shell is
not in the set of void shells
- Each shell in the IfcManifoldSolidBrep shall be
referenced only once.
- All the faces of all the shells in the IfcAdvancedBrep
and the IfcAdvancedBrepWithVoids.Voids shall be of type
IfcAdvancedFace.
"
5344;IfcSweptAreaSolid;"
Definition from ISO/CD 10303-42:1992: The swept area
solid entity collects the entities which are defined
procedurally by sweeping action on planar bounded surfaces.
The position is space of the swept solid will be dependent
upon the position of the swept area. The swept area will be
a face of the resulting swept area solid, except for the
case of a revolved area solid with angle equal to 2π
(or 360 degrees).
The swept area is defined by a
cross section (also referred to as profile), which is given
as a closed two-dimensional boundary on an implicit plane.
The swept area is defined in the xy plane of the position
coordinate system, which is given for the swept area solid.
NOTE Corresponding ISO 10303-42 entity: swept_area_solid, The data type of SweptArea is modified and given by a profile definition (IfcProfileDef). A position coordinate system is defined by the Position attribute has been added. Please refer to ISO/IS 10303-42:1994, p. 183 for the final definition of the formal standard.
HISTORY New entity in IFC Release 1.5, the capabilities have been enhanced in IFC Release 2x.
"
5352;IfcExtrudedAreaSolid;"
The IfcExtrudedAreaSolid is defined by sweeping a cross
section provided by a profile definition. The direction of the
extrusion is given by the ExtrudedDirection attribute and
the length of the extrusion is given by the Depth
attribute. If the planar area has inner boundaries (holes
defined), then those holes shall be swept into holes of the solid.
The extruded direction can be any direction which is not
perpendicular to the z axis of the position coordinate system of
the profile.
The following definitions from ISO 10303-42 apply:
An extruded area
solid is a solid defined by sweeping a bounded planar surface. The
direction of translation is defined by a direction vector, and the
length of the translation is defined by a distance depth. The
planar area may have holes which will sweep into holes in the
solid.
The ExtrudedDirection is given within the position
coordinate system as defined by
IfcSweptAreaSolid.Position. Extrusions are not restricted
to be perpendicular to the extruded surface of the profile.
Figure 255 illustrates geometric parameters of the extruded area solid. The extruded area solid defines the extrusion of a 2D area (given by a profile definition) by an direction and depth. The result is a
solid. The swept area is given by a profile definition. This profile is defined:
- as a 2D bounded curve within the xy plane of the position coordinate system,
- as a 2D bounded curve with holes within the xy plane of the position coordinate system,
- or as a 2D primitive, defined within a 2D position coordinate system, that is placed relative to the xy plane of the position coordinate system
![]() |
Figure 255 — Extruded area solid geometry |
NOTE Corresponding ISO 10303-42 entity: extruded_area_solid. Please refer to ISO/IS 10303-42:1994, p. 183 for the final definition of the formal standard. The data type of the inherited SweptArea attribute is different, i.e. of type IfcProfileDef. The Position attribute has been added to position the cross section used for the linear extrusion.
HISTORY New entity in IFC Release 1.5, capabilities of this entity have been enhanced in IFC Release 2x.
Texture use definition
For side faces, textures are aligned facing upright continuously
along the sides with origin at the first point of an arbitrary
profile, and following the outer bound of the profile
counter-clockwise (as seen from above). For parameterized profiles,
the origin is defined at the +Y extent for rounded profiles (having
no sharp edge) and the first sharp edge counter-clockwise from the
+Y extent for all other profiles. Textures are stretched or
repeated on each side along the outer boundary of the profile
according to RepeatS. Textures are stretched or repeated
on each side along the extrusion axis according to
RepeatT.
For top and bottom caps, textures are aligned facing
front-to-back, with the origin at the minimum X and Y extent.
Textures are stretched or repeated on the top and bottom to the
extent of each face according to RepeatS and
RepeatT.
For profiles with voids, textures are aligned facing upright
along the inner side with origin at the first point of an arbitrary
profile, and following the inner bound of the profile clockwise (as
seen from above). For parameterized profiles, the origin of inner
sides is defined at the +Y extent for rounded profiles (having no
sharp edge such as hollow ellipses or rounded rectangles) and the
first sharp edge clockwise from the +Y extent for all other
profiles.
Figure 256 illustrates default texture mapping with a repeated texture (RepeatS=True and RepeatT=True). The image on the left shows the texture where the S axis points to the right and the T axis points up. The image on the right shows the texture applied to the geometry where the X axis points back to the right, the Y axis points back to the left, and the Z axis points up. For an IfcExtrudedAreaSolid having a profile of IfcIShapeProfileDef, the side texture coordinate origin is the first corner counter-clockwise from the +Y axis, which equals
(-0.5*IfcIShapeProfileDef.OverallWidth, +0.5*IfcIShapeProfileDef.OverallDepth), while the top (end cap)
texture coordinates start at (-0.5*IfcIShapeProfileDef.OverallWidth,
-0.5*IfcIShapeProfileDef.OverallDepth).
![]() |
Figure 256 — Extruded area solid textures |
"
5357;IfcExtrudedAreaSolidTapered;"
IfcExtrudedAreaSolidTapered is defined by sweeping a cross
section along a linear spine. The cross section may change along
the sweep from the shape of the start cross section into the
shape of the end cross section. The resulting solid is bounded by
three or more faces: A start face, an end face (each defined by
start and end planes and sections), and one or more lateral
faces. Each lateral face is a ruled surface defined by a pair of
corresponding edges of the start and end section.
NOTE Given that the start and end section is
provided by a polygon, the corresponding vertices of the start
and end cross section are connected, forming a quadrilateral
polygon between each pair of corresponding vertices. The surface
defined by the bounding quadrilateral polygon is a ruled surface,
that could be approximated by triangulation.
The linear spine is defined by:
- Start point:
SELF\IfcSweptAreaSolid.Position.Location
- Direction:
SELF\IfcExtrudedAreaSolid.ExtrudedDirection
- Distance: SELF\IfcExtrudedAreaSolid.Depth
The start cross section is defined by
SELF\IfcSweptAreaSolid.SweptArea:
- A bounded planar surface lying in the XY plane of the
position coordinate system defined by
SELF\IfcSweptAreaSolid.Position.P[1] and
SELF\IfcSweptAreaSolid.Position.P[2]
- The linear spine starts at the plane of the start cross
section. The spine is not necessarily perpendicular to the
plane.
The end cross section is defined by EndSweptArea:
- A bounded planar surface lying in the XY plane of the
position coordinate system defined by translating the start
position coordinates provided by
SELF\IfcSweptAreaSolid.Position along the spine direction
by the spine distance. The plane of the end cross section is
coplanar to the plane of the start cross section.
-
- The end cross section is topologically similar to the start
cross section (i.e. having the same number of vertices and
edges).
- The end cross section can either be defined by the same
paramteric profile using different parameter values, or by a 2D
Cartesian transformation of the start profile within the end
cross section plane.
In case of two parameterized profiles the shape is constructed
as follows:
- The end profile, defined by a cross section based on the same
profile paramterization as the start profile, is translated by
the spine distance along the spine direction.
- It may be shifted within the XY plane of the end postion
coordinate system and may be twisted using the rotation
parameter.
- The shift and rotation parameter are provided by the end
cross section being of type IfcParameterizedProfileDef,
where
- Shift is
EndSweptArea\IfcParameterizedProfileDef.Position.Location
- Rotation is
EndSweptArea\IfcParameterizedProfileDef.Position.RefDirection
- Corresponding vertices of the start and end cross section are
connected. Lateral faces are constructed as ruled surfaces
between corresponding edges of start and end cross section.
In case of Cartesian transformation of the start cross section
the shape is constructed as follows:
- The cross section curve, which starts as a curve in the XY
plane of the position coordinate system, is first scaled about
the origin by the scale parameter. It is then translated by the
spine distance along the spine direction. It maybe twisted by
using the rotation parameter.
- The scale and rotation parameter are provided by the end
cross section being of type IfcDerivedProfileDef, where
- Scale is
EndSweptArea\IfcDerivedProfileDef.Operator.Scale
- Rotation is
EndSweptArea\IfcDerivedProfileDef.Operator.Axis1
- Corresponding vertices of the start and end cross section are
connected. Lateral faces are constructed as ruled surfaces
between corresponding edges of start and end cross section.
HISTORY New entity in IFC2x4.
Informal propositions
- Mirroring within IfcDerivedProfileDef.Operator shall
not be used
"
5360;IfcRevolvedAreaSolid;"
An IfcRevolvedAreaSolid is a solid created by revolving
a cross section provided by a profile definition about an axis. The
axis and the cross section shall be in the same plane.
NOTE Both the axis and the cross section are
required to lie in the xy plane of the object position coordinate
system.
The following definitions from ISO 10303-42 apply:
A revolved area solid
is a solid formed by revolving a planar bounded surface about an
axis. The axis shall be in the plane of the surface and the axis
shall not intersect the interior of the bounded surface. The
bounded surface may have holes which will sweep into holes in the
solid. The direction of revolution is clockwise when viewed along
the axis in the positive direction. More precisely if A is
the axis location and d is the axis direction and C
is an arc on the surface of revolution generated by an arbitrary
point p on the boundary of the swept area, then C
leaves p in direction d x (p - A) as
the area is revolved.
Figure 262 illustrates geometric parameters of the revolved solid. The revolved area solid defines the revolution of a 2D area (given by a profile definition) by an axis and angle. The result is a solid. The swept area is given by a profile definition. This profile is defined:
- as a 2D bounded curve within the xy plane of the position coordinate system,
- as a 2D bounded curve with holes within the xy plane of the position coordinate system,
- or as a 2D primitive, defined within a 2D position coordinate system, that is placed relative to the xy plane of the position coordinate system
The AxisLine can have any orientation within the XY plane, it does not have to be parallel to the y-axis as shown in the illustration.
![]() |
Figure 262 — Revolved area solid geometry |
NOTE Corresponding ISO 10303-42 entity: revolved_area_solid. Please refer to ISO/IS 10303-42:1994, p. 184 for the final definition of the formal standard. The data type of the inherited SweptArea attribute is different, i.e. of type IfcProfileDef. The position attribute has been added to position the cross section used for the revolution.
HISTORY New entity in IFC Release 1.5, capabilities of this entity have been enhanced in IFC Release 2x.
Informal propositions:
- The AxisLine shall lie in the plane of the
SweptArea (as defined at supertype
IfcSweptAreaSolid).
- The AxisLine shall not intersect the interior of the
SweptArea (as defined at supertype
IfcSweptAreaSolid).
- The Angle shall be between 0° and 360°, or 0
and 2π (depending on the unit type for
IfcPlaneAngleMeasure).
Texture Use Definition
For side faces, textures are aligned facing upright along the
sides with origin at the first point of an arbitrary profile, and
following the outer bound of the profile counter-clockwise (as seen
from above). For parameterized profiles, the origin is defined at
the +Y extent for rounded profiles (having no sharp edge) and the
first sharp edge counter-clockwise from the +Y extent for all other
profiles. Textures are stretched or repeated on each side along the
outer boundary of the profile according to RepeatS.
Textures are stretched or repeated on each side along the outermost
(longest) revolution path according to RepeatT, where
coordinates are compressed towards the axis of revolution.
For top and bottom caps, textures are aligned facing
front-to-back, with the origin at the minimum X and Y extent.
Textures are stretched or repeated on the top and bottom to the
extent of each face according to RepeatS and
RepeatT.
For profiles with voids, textures are aligned facing upright
along the inner side with origin at the first point of an arbitrary
profile, and following the inner bound of the profile clockwise (as
seen from above). For parameterized profiles, the origin of inner
sides is defined at the +Y extent for rounded profiles (having no
sharp edge such as hollow ellipses or rounded rectangles) and the
first sharp edge clockwise from the +Y extent for all other
profiles.
Figure 263 illustrates default texture mapping with a repeated texture (RepeatS=True and RepeatT=True). The image on the left shows the texture where the S axis points to the right and the T axis points up. The image on the right shows the texture applied to the geometry where the X axis points back to the right, the Y axis points back to the left, and the Z axis points up. For an IfcRevolvedAreaSolid having a profile of IfcTShapeProfileDef and revolved at 22.5 degrees, the side texture coordinate origin is the first corner counter-clockwise from the +Y axis, which equals (-0.5*IfcTShapeProfileDef.OverallWidth, +0.5*IfcTShapeProfileDef.OverallDepth), while the top (end cap) texture coordinates start at (-0.5*IfcTShapeProfileDef.OverallWidth, -0.5*IfcTShapeProfileDef.OverallDepth).
![]() |
Figure 263 — Revolved area solid textures |
"
5367;IfcRevolvedAreaSolidTapered;"
IfcRevolvedAreaSolidTapered is defined by revolving a
cross section along a circular arc. The cross section may change
along the revolving sweep from the shape of the start cross
section into the shape of the end cross section. Corresponding
vertices of the start and end cross sections are then connected.
The bounded surface may have holes which will sweep into holes in
the solid.
The rotation axis is defined by:
- Start point:
SELF\IfcSweptAreaSolid.Position.Location
- Direction: SELF\IfcRevolvedAreaSolid.Axis
- Rotation axis: SELF\IfcRevolvedAreaSolid.AxisLine,
created from start point and direction by appying a 1 unit
magnitude.
- Orientation: Positive angles are applied clockwise when
looking into the positive direction of the rotation axis.
The start cross section is defined by
SELF\IfcSweptAreaSolid.SweptArea:
- A bounded planar surface lying in the XY plane of the
position coordinate system defined by
SELF\IfcSweptAreaSolid.Position.P[1] and
SELF\IfcSweptAreaSolid.Position.P[2]
- The rotation axis lies in the plane of the start cross
section but shall not intersect the interior of the start cross
section.
The end cross section is defined by EndSweptArea:
- A bounded planar surface lying in the XY plane of the
position coordinate system defined by rotating the start position
coordinates provided by SELF\IfcSweptAreaSolid.Position
around the rotation axis by the angle given by
SELF\IfcRevolvedAreaSolid.Angle.
-
- The end cross section is topologically similar to the start
cross section (having the same number of vertices and edges).
- The end cross section can either be defined by the same
paramteric profile using different parameter values, or by a 2D
Cartesian transformation of the start profile within the end
cross section plane.
The solid is generated by transforming the start cross section
into to end cross section. A start face, an end face (each
defined by start and end cross sections), and one or more lateral
faces. Each lateral face is a ruled surface defined by a pair of
corresponding edges of the start and end section. The ruled
surfaces are constructed in the cylindrical coordinate space
defined by the supertype IfcRevolvedAreaSolid.""
HISTORY New entity in IFC2x4.
Informal propositions
- Mirroring within IfcDerivedProfileDef.Operator shall
not be used
"
5370;IfcSurfaceCurveSweptAreaSolid;"
The IfcSurfaceCurveSweptAreaSolid is the result of
sweeping an area along a directrix that lies on a reference
surface. The swept area is provided by an IfcProfileDef
(or subtypes). The profile definition is based on a 2D coordinate
system, which is inserted into the XY plane of the 3D
Position coordinate system inherited from the supertype
IfcSweptAreaSolid.
The following definitions from ISO 10303-42 apply:
A surface curve swept
area solid is a type of swept area solid which is the result of
sweeping a face along a Directrix lying on a
ReferenceSurface. The orientation of the
SweptArea is related to the direction of the surface
normal.
The
SweptArea is required to be a curve bounded surface lying
in the plane z = 0 and this is swept along the Directrix
in such a way that the origin of the local coordinate system used
to define the SweptArea is on the Directrix and
the local x-axis is in the direction of the normal to the
ReferenceSurface at the current point. The resulting solid
has the property that the cross section of the surface by the
normal plane to the Directrix at any point is a copy of
the SweptArea.
The orientation of
the SweptArea as it sweeps along the Directrix is
precisely defined by a Cartesian Transformation Operator 3D with
attributes:
- LocalOrigin
as point (0; 0; 0),
- Axis1 as
the normal N to the ReferenceSurface at the point of the
Directrix with parameter u.
- Axis3 as
the direction of the tangent vector t at the point of the
Directrix with parameter u.
The remaining attributes are defaulted to define a corresponding
transformation matrix T(u), which varies with the
Directrix parameter u.
NOTE The
geometric shape of the solid is not dependent upon the curve
parameterization; the volume depends upon the area swept and the
length of the Directrix.
The attributes of the Cartesian Transformation Operator (as
shown above) should apply to the Position coordinate
system, in which the profile is inserted. The Directrix
and the ReferenceSurface are positioned within the 3D
Position coordinate system.
NOTE Corresponding ISO 10303-42 entity: surface_curve_swept_area_solid. Please refer to ISO 10303-42 ed.2:1999, p. 274 for the definition in the international standard.
HISTORY New entity in IFC2x2.
Informal propositions:
- The SweptArea shall lie in the plane z = 0.
- The Directrix shall lie on the
ReferenceSurface.
"
5375;IfcFixedReferenceSweptAreaSolid;"
A fixed reference swept area solid is a type of swept area solid
which is the result of sweeping a surface along a
Directrix. The orientation of the curve during the
sweeping operation is controlled by the FixedReference
direction.
The SweptArea is required to be a curve bounded surface
lying in the plane z = 0 and this is swept along the
Directrix in such a way that the origin of the local
coordinate system used to define the SweptArea is on the
Directrix and the local X axis is in the direction of the
projection of FixedReference onto the normal plane to the
directrix at this point. The resulting solid has the property that
the cross section of the surface by the normal plane to the
Directrix at any point is a copy of the
SweptArea.
NOTE The swept face
is given by IfcProfileDef (or subtypes), the profile
definition is given within a 2D coordinate system, which is
inserted into the XY plane of the Position coordinate
system inherited from the supertype
IfcSweptAreaSolid.
The orientation of the SweptArea as it sweeps along the
Directrix is precisely defined by a
CartesianTransformationOperator3d with attributes:
- LocalOrigin as point (0; 0; 0),
- Axis1 as the FixedReference.
- Axis3 as the direction of the tangent vector t
at the point of the Directrix with parameter
u.
The remaining attributes are defaulted to define a corresponding
transformation matrix T(u), which varies with the
Directrix parameter u.
NOTE The geometric shape of the
solid is not dependent upon the curve parameterization; the volume
depends upon the area swept and the length of the
Directrix.
The attributes of the Cartesian Transformation Operator (as
shown above) should apply to the Position coordinate
system, in which the profile is inserted. The Directrix
and the FixedReference are positioned within the 3D
Position coordinate system.
NOTE The entity is defined in analogy to the ISO 10303-42 entity: fixed_reference_swept_surface. Please refer to ISO/DIS 10303-42:2003(E) p. 103.
HISTORY New entity in IFC2x4.
Informal propositions:
- The SweptArea shall lie in the plane z = 0.
- The FixedReference shall not be parallel to a tangent
vector to the directrix at any point along this curve.
- The Directrix curve shall be tangent continuous.
"
5380;IfcCsgSolid;"
Definition from ISO/CD 10303-42:1992: A solid
represented as a CSG model is defined by a collection of
so-called primitive solids, combined using regularized
Boolean operations. The allowed operations are
intersection, union, and difference. As a special case a
CSG solid can also consists of a single CSG primitive.
A CSG solid requires two kinds of information for its
complete definition: geometric and structural.
- The geometric information is conveyed by solid models.
These typically primitive volumes such as cylinders, wedges
and extrusions, but can include general B-Rep models. Solid
models can also be half space solids.
- The structural information is in a tree (strictly an
acyclic directed graph) of Boolean result and CSG solids,
which represent a ‘recipe’ for building the
solid. The terminal nodes are the geometric primitives and
other solids. Every CSG solid has precisely one Boolean
result associated with it which is the root of the tree
that defines the solid. (There may be further Boolean
results within the tree as operands). The significance of a
CSG solid entity is that the solid defined by the
associated tree is thus identified as a significant object
itself, and in this way it is distinguished from other
Boolean result entities representing intermediate results
during the construction process.
Definition from IAI: The following primitive volumes
can be parts of the CSG tree: solid models, i.e. faceted
B-Rep (IfcFacetedBrep, IfcFacetedBrepWithVoids),
swept area solid (IfcExtrudedAreaSolid,
IfcRevolvedAreaSolid, IfcSurfaceCurveSweptAreaSolid),
swept disk solids (IfcSweptDiskSolid), half space
solids (IfcHalfSpaceSolid and subtypes), and CSG
primitives (subtypes of IfcCsgPrimitive3D).
NOTE Corresponding ISO 10303-42 entity: csg_solid, please refer to ISO/IS 10303-42:1994, p.174 for the final definition of the formal standard.
HISTORY New class in IFC Release 1.5.1
"
5385;IfcCsgPrimitive3D;"
IfcCsgPrimitive3D is an abstract supertype of all three dimensional primitives used as either tree root item, or as Boolean results within a CSG solid model. All 3D CSG primitives are defined within a three-dimensional placement coordinate system.
NOTE˙ No directly corresponding ISO 10303-42 entity, the select type primitive_3d covers the same individual 3D CSG primitives, the position attribute has been added to apply equally to all subtypes. Please refer to ISO/IS 10303-42:1994, p. 234 for the final definition of the formal standard.
HISTORY˙ New entity in IFC2x3.
"
5393;IfcBlock;"
The IfcBlock is a Construction Solid Geometry (CSG) 3D
primitive. It is defined by a position and a positve distance along
the three orthogonal axes. The inherited Position
attribute has the IfcAxisPlacement3D type and
provides:
- SELF\IfcCsgPrimitive3D.Position: The location and
orientation of the axis system for the primitive.
- SELF\IfcCsgPrimitive3D.Position.Location: The block
has one vertex at location and the edges are aligned with the
placement axes in the positive sense.
The XLength, YLength, and ZLength
attributes define the size of the IfcBlock along the three
axes.
The following definitions from ISO 10303-42 apply:
A block is a solid
rectangular parallelepiped, defined with a location and placement
coordinate system. The block is specified by the positive lengths
x, y, and z along the axes of the placement coordinate system, and
has one vertex at the origin of the placement coordinate
system.
Figure 250 illustrates geometric parameters of a block where the block positioned within its own placement coordinate system. The values for XLength, YLength, and ZLength are applied to the positive direction of the X, Y, and Z axis.
![]() |
Figure 250 — Block geometry |
NOTE Corresponding ISO 10303-42 entity: block, the position attribute has been promoted to the immediate supertype IfcCsgPrimitive3D. Please refer to ISO 10303-42:1994, p. 244 for the definition in the international standard.
HISTORY New entity in IFC2x3.
Texture use definition
On each side face, textures are aligned facing upright. On the
top and bottom faces, textures are aligned facing front-to-back.
Textures are stretched or repeated to the extent of each face
according to RepeatS and RepeatT.
Figure 251 illustrates default texture mapping with a clamped texture (RepeatS=False and RepeatT=False). The image on the left shows the texture where the S axis points to the right and the T axis points up. The image on the right shows the texture applied to the geometry where the X axis points back to the right, the Y axis points back to the left, and the Z axis points up.
![]() |
| Side |
Normal |
Origin X |
Origin Y |
Origin Z |
S Axis |
T Axis |
| Left |
-X |
0 |
+YLength |
0 |
-Y |
+Z |
| Right |
+X |
0 |
+YLength |
0 |
+Y |
+Z |
| Front |
+X |
0 |
0 |
0 |
+X |
+Z |
| Back |
+Y |
+XLength |
+YLength |
0 |
-X |
+Z |
| Bottom |
-Z |
+XLength |
0 |
0 |
-X |
+Y |
| Top |
+Z |
0 |
0 |
+ZLength |
+X |
+Y |
|
Figure 251 — Block textures |
"
5397;IfcRectangularPyramid;"
The IfcRectangularPyramid is a Construction Solid
Geometry (CSG) 3D primitive. It is a solid with a rectangular base and
a point called apex as the top. The tapers from the base to the
top. The axis from the center of the base to the apex is
perpendicular to the base. The inherited Position
attribute defines the IfcAxisPlacement3D and provides the
location and orientation of the pyramid:
- SELF\IfcCsgPrimitive3D.Position: The location and
orientation of the axis system for the primitive.
- SELF\IfcCsgPrimitive3D.Position.Location: The center
of the circular area being the bottom face of the cone.
- SELF\IfcCsgPrimitive3D.Position.Position[3]: The
z-axis of the inherited placement coordinate system provides the
center axis of the IfcRightCircularCone, and the apex is
at the Height value applied to the positive direction of
the z-axis. The BottomRadius defines the circular base at
the xy-plane of the placement coordinate system.
As shown in Figure 260, the pyramid is positioned within its own placement coordinate system. The origin is the center of the bottom rectangle, that lies in the XY plane. The apex lies on the positive z axis at [0, 0, Height].
![]() |
Figure 260 — Rectangular pyramid geometry |
NOTE Corresponding ISO 10303 entity: right_circular_cone, the position attribute has been promoted to the immediate supertype IfcCsgPrimitive3D. No semi_angle attribute, and the radius defines the bottom radius, since only a non-truncated cone is in scope. Please refer to ISO/IS 10303-42:1994, p. 176 for the final definition of the formal standard.
HISTORY New entity in IFC2x3
Texture use definition
On each triangular side face, textures are aligned facing upright.
Textures are stretched or repeated to the extent of the base of each face according to RepeatS.
Textures are stretched or repeated towards the top point according to Repeat T,
where the top point has coordinates of (0.5,1.0) if RepeatT is False.
On the bottom face, textures are aligned facing front-to-back.
Figure 261 illustrates default texture mapping with a clamped texture (RepeatS=False and RepeatT=False). The image on the left shows the texture where the S axis points to the right and the T axis points up. The image on the right shows the texture applied to the geometry where the X axis points back to the right, the Y axis
points back to the left, and the Z axis points up.
![]() |
| Side |
Normal |
Origin X |
Origin Y |
Origin Z |
S Axis |
T Axis |
| Left |
-X |
0 |
+YLength |
0 |
-Y |
(towards top point) |
| Right |
+X |
0 |
+YLength |
0 |
+Y |
(towards top point) |
| Front |
+X |
0 |
0 |
0 |
+X |
(towards top point) |
| Back |
+Y |
+XLength |
+YLength |
0 |
-X |
(towards top point) |
| Bottom |
-Z |
+XLength |
0 |
0 |
-X |
+Y |
|
Figure 261 — Right circular cone textures |
"
5401;IfcRightCircularCylinder;"
The IfcRightCircularCylinder is a Construction Solid
Geometry (CSG) 3D primitive. It is a solid with a circular base and
top. The cylindrical surface between if formed by points at a fixed
distance from the axis of the cylinder. The inherited
Position attribute defines the IfcAxisPlacement3D
and provides:
- SELF\IfcCsgPrimitive3D.Position: The location and
orientation of the axis system for the primitive.
- SELF\IfcCsgPrimitive3D.Position.Location: The center
of the circular area being the bottom face of the cylinder.
- SELF\IfcCsgPrimitive3D.Position.Position[3]: The z
axis provides the center axis and the height is measured from the
origin along the positive direction of the z axis.
The following definitions from ISO 10303-42 apply:
A right circular
cylinder is a CSG primitive in the form of a solid cylinder of
finite height. It is defined by an axis point at the centre of one
planar circular face, an axis, a height, and a radius. The faces
are perpendicular to the axis and are circular discs with the
specified radius. The height is the distance from the first
circular face centre in the positive direction of the axis to the
second circular face centre.
Figure 266 illustrates geometric parameters of the cylinder. The cylinder is positioned within its own placement coordiante system. The origin is the center of the bottom circular disk, that lies in the XY plane. The center of the top circular disk is on the positive z axis at [0, 0, Height].
![]() |
Figure 266 — Right circular cylinder geometry |
NOTE Corresponding ISO 10303 entity: right_circular_cyclinder, the position attribute has been promoted to the immediate supertype IfcCsgPrimitive3D. Please refer to ISO/IS 10303-42:1994, p. 177 for the definition in the international standard.
HISTORY New entity in IFC2x3.
Texture use definition
On the circular side, textures are aligned facing upright with
origin at the back (+Y direction) revolving counter-clockwise.
Textures are stretched or repeated to the extent of the
circumference according to RepeatS. Textures are stretched or
repeated to the extent of the Height according to
RepeatT.
On the top and bottom faces, textures are aligned facing
front-to-back, with the center of the circle aligned to the center
of the texture.
Figure 267 illustrates default texture mapping with a clamped texture (RepeatS=False and RepeatT=False). The image on the left shows the texture where the S axis points to the right and the T axis points up. The image on the right shows the texture applied to the geometry where the X axis points back to the right, the Y axis
points back to the left, and the Z axis points up.
![]() |
| Side |
Normal |
Origin X |
Origin Y |
Origin Z |
S Axis |
T Axis |
| Side |
-Y |
0 |
+Radius |
0 |
-X |
+Z |
| Bottom |
-Z |
0 |
0 |
0 |
-X |
+Y |
| Top |
+Z |
0 |
0 |
+Height |
+X |
+Y |
|
Figure 267 — Right circular cylinder textures |
"
5404;IfcRightCircularCone;"
The IfcRightCircularCone is a Construction Solid
Geometry (CSG) 3D primitive. It is a solid with a circular base and
a point called apex as the top. The tapers from the base to the
top. The axis from the center of the circular base to the apex is
perpendicular to the base. The inherited Position
attribute defines the IfcAxisPlacement3D and provides the
location and orientation of the cone:
- SELF\IfcCsgPrimitive3D.Position: The location and
orientation of the axis system for the primitive.
- SELF\IfcCsgPrimitive3D.Position.Location: The center
of the circular area being the bottom face of the cone.
- SELF\IfcCsgPrimitive3D.Position.Position[3]: The
z-axis of the inherited placement coordinate system provides the
center axis of the IfcRightCircularCone, and the apex is
at the Height value applied to the positive direction of
the z-axis. The BottomRadius defines the circular base at
the xy-plane of the placement coordinate system.
Figure 264 illustrates geometric parameters of the cone. The cone is positioned within its own placement coordinate system. The origin is the center of the bottom circular disk, that lies in the XY plane. The apex lies on the positive z axis at [0, 0, Height].
![]() |
Figure 264 — Right circular cone geometry |
NOTE Corresponding ISO 10303 entity: right_circular_cone, the position attribute has been promoted to the immediate supertype IfcCsgPrimitive3D. No semi_angle attribute, and the radius defines the bottom radius, since only a non-truncated cone is in scope. Please refer to ISO/IS 10303-42:1994, p. 176 for the final definition of the formal standard.
HISTORY New entity in IFC2x3
Texture use definition
On the circular side, textures are aligned facing upright with
origin at the back (+Y direction) revolving counter-clockwise.
Textures are stretched or repeated to the extent of the base
circumference according to RepeatS. Textures are compressed
linearly going upwards towards the top point according to
RepeatT.
On the bottom face, textures are aligned facing front-to-back,
with the center of the circle aligned to the center of the
texture.
Figure 265 illustrates default texture mapping with a clamped texture (RepeatS=False and RepeatT=False). The image on the left shows the texture where the S axis points to the right and the T axis points up. The image on the right shows the texture applied to the geometry where the X axis points back to the right, the Y axis points back to the left, and the Z axis points up.
![]() |
| Side |
Normal |
Origin X |
Origin Y |
Origin Z |
S Axis |
T Axis |
| Side |
-Y |
0 |
+Radius |
0 |
-X |
(towards top point) |
| Bottom |
-Z |
0 |
0 |
0 |
-X |
+Y |
|
Figure 265 — Right circular cone textures |
"
5407;IfcSphere;"
The IfcSphere is a Construction Solid Geometry (CSG) 3D
primitive. It is a solid where all points at the surface have the
same distance from the center point. The inherited
Position attribute defines the IfcAxisPlacement3D
and provides:
- SELF\IfcCsgPrimitive3D.Position: The location and
orientation of the axis system for the primitive.
- SELF\IfcCsgPrimitive3D.Position.Location: The center
of the sphere.
- SELF\IfcCsgPrimitive3D.Position.Position[3]: The z
axis points at its positve direction towards the north pole, and by
its negative directions towards the south pole.
The following definitions from ISO 10303-42 apply:
A sphere is a CSG
primitive with a spherical shape defined by a centre and a
radius.
Figure 270 illustrates geometric parameters of the sphere. The sphere is positioned within its own placement coordiante system. The origin is the center of the sphere.
![]() |
Figure 270 — Sphere geometry |
NOTE Corresponding STEP entity: sphere, the position attribute, including the centre point, has been promoted to the immediate supertype IfcCsgPrimitive3D. Please refer to ISO/IS 10303-42:1994, p. 175 for the final definition of the formal standard.
HISTORY New entity in IFC2x3.
Texture Use Definition
Textures are aligned facing upright with origin at the back (+Y direction) revolving counter-clockwise. Textures are stretched or repeated to the extent of the circumference at the equator according to RepeatS and RepeatT.
Figure 271 illustrates default texture mapping with a clamped texture (RepeatS=False and RepeatT=False). The image on the left shows the texture where the S axis points to the right and the T axis points up. The image on the right shows the texture applied to the geometry where the X axis points back to the right, the Y axis points back to the left, and the Z axis points up.
![]() |
| Side |
Normal |
Origin X |
Origin Y |
Origin Z |
S Axis |
T Axis |
| Side |
-Y |
0 |
+Radius |
0 |
(-X, then curving counter-clockwise) |
(+Y, then curving towards top) |
|
Figure 271 — Sphere textures |
"
5409;IfcSweptDiskSolid;"
Definition from ISO 10303-42:2002: A swept
disk solid is the solid produced by sweeping a circular disk
along a three dimensional curve. During the sweeping operation
the normal to the plane of the circular disk is in the direction
of the tangent to the directrix curve and the center of the disk
lies on the directrix. The circular disk may, optionally, have a
central hole, in this case the resulting solid has a through
hole, or, an internal void when the directrix forms a close
curve.
The StartParam and
EndParam parameter are optional, if not provided they
default to the start and end of the Directrix. Only if the
Directrix is given by a bounded or by a closed curve, it
is permissible to omit the values of StartParam and
EndParam.
If the transitions between consecutive segments of the
Directrix are not tangent continuous, the resulting solid
is created by a miter at half angle between the two segments.
Informal proposition restricts the permissible angle between two
non-tangent continuous segments.
Figure 272 illustrates an example.
- Directrix given as IfcCompositeCurve being
tangent continuous between its segments
- Directrix being a bounded and open curve
- No StartParam and EndParam are provided, start
and end default to start and end of the bounded curve of the
Directrix
NOTE Although the example shows a Directrix as a composite curve on a planar reference surface, the definition of IfcSweptDiskSolid is not restricted to be based on planer curves. However view definitions or implementer agreements may provide restrictions.
![]() |
Figure 272 — Swept disk solid geometry |
NOTE Corresponding ISO 10303-42 entity: swept_disk_solid. Please refer to ISO/FDIS 10303-42:2002, p. 282 for the definition of the formal standard.
HISTORY New entity in IFC Release 2x2.
IFC2x4 CHANGE The attribute StartParam and EndParam have been made optional.
Informal proposition
- If the Directrix curve definition is not tangent
continuous, the transition between the segments has to be within
an acceptable limit of tangent discontinuity. Very sharp edges
may result in nearly impossible miter. Implementer agreements may
define acceptable limits for tangent discontinuity.
- The segments of the Directrix shall be long enough to
apply the Radius. In case of an arc segment forming part
of the Directrix ,its radius shall be greater then the
disk Radius
- The Directrix shall not be based on an intersecting
curve.
"
5419;IfcSweptDiskSolidPolygonal;"
The IfcSweptDiskSolidPolygonal is a IfcSweptDiskSolid where the Directrix is restricted to be provided by an IfcPolyline only. An optional FilletRadius attribute can be asserted, it is then applied as a fillet to all transitions between the segments of the IfcPolyline.
HISTORY New entity in IFC2x4.
Informal proposition
- The FilletRadius, if provided, has to be smaller then
or equal to the length of the start and end segment of the
IfcPolyline, and smaller then or equal to one half of the
lenght of the shortest inner segment.
"
5423;IfcSectionedSpine;"
Definition from ISO 10303-42:1999: A sectioned
spine is a representation of the shape of a three dimensional
object composed of a spine curve and a number of planar cross
sections. The shape is defined between the first element of cross
sections and the last element of this set.
NOTE A sectioned spine may be used to represent a surface or a
solid but the interpolation of the shape between the
cross-sections is not defined. For the representation of a solid
all cross-sections are closed curves.
A sectioned spine
(IfcSectionedSpine) is a representation of the shape of a
three dimensional object composed by a number of planar cross
sections, and a spine curve. The shape is defined between the
first element of cross sections and the last element of the cross
sections. A sectioned spine may be used to represent a surface or
a solid but the interpolation of the shape between the cross
sections is not defined.
For the representation of a solid all cross sections are
areas. For representation of a surface all cross sections are
curves. The cross sections are defined as profiles, whereas the
consecutive profiles may be derived by a transformation of the
start profile or the previous consecutive profile.
The spine curve shall be of type IfcCompositeCurve,
each of its segments (IfcCompositeCurveSegment) shall
correspond to the part between exactly two consecutive
cross-sections.
NOTE: Corresponding ISO 10303 entity: sectioned spine. Please refer to ISO/DIS 10303-42-ed2:1999, p. 282 for the definition of the formal standard. The cross sections are defined in IFC as IfcProfileDef. The position coordinate systems are added.
HISTORY New entity in IFC Release 2x.
Figure 268 illustrates an example of an IfcSectionedSpine.
- The SpineCurve is given by an IfcCompositeCurve with two Segments. The Segments[1] has a ParentCurve of type IfcPolyline and a Transition = CONTSAMEGRADIENT. The Segments[2] has a ParentCurve of type
IfcTrimmedCurve and a Transition = DISCONTINUOUS.
- Each CrossSectionPosition lies at a start or end point of the Segments.
- Each CrossSections are inserted by the CrossSectionPositions. The first two cross sections are of
type IfcRectangleProfileDef, the third is of type IfcDerivedProfileDef.
![]() |
Figure 268 — Sectioned spine geometry |
Figure 269 illustrates the final result of the IfcSectionedSpine. The body (shown transparently) is not fully defined by the
exchange definition.
![]() |
Figure 269 — Sectioned spine result |
Informal propositions
- none of the cross sections, after being placed by the cross section positions, shall intersect
- none of the cross sections, after being placed by the cross section positions, shall lie in the same plane
- the local origin of each cross section position shall lie at the beginning or end of a composite curve segment.
"
5431;IfcGeometricSet;"
Definition from ISO/CD 10303-42:1992: This entity is intended for the transfer of models when a topological structure is not available.
The IfcGeometricSet is used for the exchange of shape representations consisting of (2D or 3D) points, curves, and/or surfaces, which do not have a topological structure (such as connected face sets or shells) and are not solid models (such as swept solids, CSG or Brep)
NOTE: Corresponding ISO 10303-42 entity: geometric_set. The derived attribute Dim has been added at this level and was therefore demoted from the geometric_representation_item. Please refer to ISO/IS 10303-42:1994, p. 190 for the final definition of the formal standard.
HISTORY: New entity in IFC Release 2x.
"
5436;IfcGeometricCurveSet;"
Definition from ISO/CD 10303-42:1992: A geometric curve set is a collection of two or three dimensional points and curves.
The IfcGeometricCurveSet is used for the exchange of shape representations consisting of (2D or 3D) points and curves only.
NOTE: Corresponding ISO 10303-42 entity: geometric_set. Please refer to ISO/IS 10303-42:1994, p. 190 for the final definition of the formal standard.
HISTORY: New entity in IFC2x2.
"
5442;IfcFaceBasedSurfaceModel;"
Definition from ISO/CD 10303-42:1992: A face based surface model is described by a set of connected face sets of dimensionality 2. The connected face sets shall not intersect except at edges and vertices, except that a face in one connected face set may overlap a face in another connected face set, provided the face boundaries are identical. There shall be at least one connected face set.
A connected face set may exist independently of a surface model.
NOTE Corresponding STEP entity: face_based_surface_model. Please refer to ISO/IS 10303-42:1994, p. 188 for the final definition of the formal standard.
HISTORY: New entity in IFC Release 2x.
Informal propositions:
- The connected face sets shall not overlap or intersect except at common faces, edges or vertices.
- The fbsm faces have dimensionality 2.
"
5445;IfcShellBasedSurfaceModel;"
Definition from ISO/CD 10303-42:1992: A shell based surface model is described by a set of open or closed shells of dimensionality 2. The shells shall not intersect except at edges and vertices. In particular, distinct faces may not intersect. A complete face of one shell may be shared with another shell. Coincident portions of shells shall both reference the same faces, edges and vertices defining the coincident region. There shall be at least one shell.
A shell may exist independently of a surface model.
NOTE Corresponding ISO 10303-42 entity: shell_based_surface_model. Please refer to ISO/IS 10303-42:1994, p. 187 for the final definition of the formal standard.
HISTORY: New entity in IFC Release 2x.
Informal propositions
- The dimensionality of the shell based surface model is 2.
- The shells shall not overlap or intersect except at common faces, edges or vertices.
"
5448;IfcBooleanClippingResult;"
A clipping result is defined as a special subtype of the general Boolean result (IfcBooleanResult). It constrains the operands and the operator of the Boolean result.
A clipping result is the Boolean difference between a solid (restricted to swept area solid) and a half space solid, whereas more than one difference operation can be applied to the Boolean result.
NOTE The IfcBooleanClippingResult is defined as a special case of the boolean_result, as defined in ISO 10303-42:1994, p. 175. It has been added to apply further constraints to the CSG representation type.
HISTORY New entity in IFC Release 2.x.
"
5468;IfcAxis2Placement2D;"
Definition from ISO/CD 10303-42:1992: The location and orientation in two dimensional space of two mutually perpendicular axes. An axis2_placement_2d is defined in terms of a point, (inherited from the placement supertype), and an axis. It can be used to locate and originate an object in two dimensional space and to define a placement coordinate system. The class includes a point which forms the origin of the placement coordinate system. A direction vector is required to complete the definition of the placement coordinate system. The reference direction defines the placement X axis direction, the placement Y axis is derived from this.
If the RefDirection attribute is not given, the placement defaults to P[1] (x-axis) as [1.,0.] and P[2] (y-axis) as [0.,1.].
NOTE Corresponding ISO 10303 name: axis2_placement_2d, please refer to ISO/IS 10303-42:1994, p. 28 for the final definition of the formal standard.
HISTORY New entity in IFC Release 1.5.
Figure 275 illustrates the definition of the IfcAxis2Placement2D within the two-dimensional coordinate system.
![]() |
Figure 275 — Axis2 placement 2D |
"
5473;IfcPlacement;"
Definition from ISO/CD 10303-42:1992: A placement entity defines the local environment for the definition of a geometry item. It locates the item to be defined and, in the case of the axis placement subtypes, gives its orientation.
Additional definition from ISO/WD SC4/WG12/N071 Part42.2 geometry_schema: A placement locates a geometric item with respect to the coordinate system of its geometric context.
IfcPlacement is an abstract supertype not to be directly instantiated, whereas the ISO 10303-42 entity placement can be instantiated to define a placement without orientation. The derived attribute Dim has been added, see also note at IfcGeometricRepresentationItem.
NOTE: Corresponding ISO 10303 entity: placement. Please refer to ISO/IS 10303-42:1994, p. 27 for the final definition of the formal standard.
HISTORY: New entity in IFC Release 1.0
"
5479;IfcGeometricRepresentationItem;"
Definition from ISO/CD 10303-43:1992: An geometric representation item is a representation item that has the additional meaning of having geometric position or orientation or both. This meaning is present by virtue of:
- being a Cartesian point or a direction
- referencing directly a Cartesian point or direction
- referencing indirectly a Cartesian point or direction
An indirect reference to a Cartesian point or direction means that a given geometric item references the Cartesian point or direction through one or more intervening geometry or topology items.
EXAMPLE: Consider a circle. It gains its geometric position and orientation by virtue of a reference to axis2_placement (IfcAxis2Placement) that is turn references a cartesian_point (IfcCartesianPoint) and several directions (IfcDirection).
EXAMPLE: Consider a manifold brep. A manifold_solid_brep (IfcManifoldSolidBrep) is a geometric_representation_item (IfcGeometricRepresentationItem) that through several layers of topological_representation_item's (IfcTopologicalRepresentationItem) references poly loops (IfcPolyLoop). Through additional intervening entities poly loops reference cartesian_point's (IfcCartesianPoint).
The derivation of the dimensionality of the IfcGeometricRepresentationItem is different to ISO 10303; there is a specific derived attribute at each class that defines the dimensionality, whereas ISO 10303 does it for the representation_context and requires all geometric_representation_item's to have the same dimensionality therein.
The definition of swept area solids as geometric representation items is different to ISO 10303; it is based on a set of predefined profiles (or cross sections), that is, a set of parameterized geometric primitives widely supported in the industry. Those profiles are used to create volumes through extrusion, revolution and cross section based sweep operations.
NOTE: Corresponding ISO 10303 entity: geometric_representation_item. Please refer to ISO/IS 10303-42:1994, p. 22 for the final definition of the formal standard. The following changes have been made: It does not inherit from ISO/IS 10303-43:1994 entity representation_item. The derived attribute Dim is demoted to the appropriate subtypes. The WR1 has not been incorporated. Not all subtypes that are in ISO/IS 10303-42:1994 have been added to the current IFC Release.
HISTORY: New entity in IFC Release 1.5
"
5496;IfcRepresentationItem;"
Definition from ISO/CD
10303-43:1992: A representation item is an element of
product data that participates in one or more representations or
contributes to the definition of another representation item. A
representation item contributes to the definition of another
representation item when it is referenced by that representation
item.
NOTE Corresponding entity in ISO 10303-43:1994: representation_item. Please refer to ISO/IS 10303-43:1994, for the final definition of the formal standard. The following changes have been made: The attribute 'name' and the WR1 have not been incorporated.
The IfcRepresentationItem is used within an IfcRepresentation (directly or indirectly through other IfcRepresentationItem's) to represent an IfcProductRepresentation. Most commonly these IfcRepresentationItem's are geometric or topological representation items, that can (but not need to) have presentation style infomation assigned.
NOTE The assignment of a style is only applicable
to the subtypes IfcGeometricRepresentationItem, IfcMappedItem and some selected subtypes of IfcTopologicalRepresentationItem (IfcVertexPoint, IfcEdgeCurve, IfcFaceSurface).
In case that presentation style information is applied, it can be either applied by an IfcStyledItem, or by an assignment to an IfcPresentationLayerWithStyle. If both are present, and both style assignments include the same subtype of IfcPresentationStyle, then the style assigned by IfcStyledItem takes priority.
Figure 281 shows an instance diagram explaining the use of IfcStyledItem and IfcPresentationLayerWithStyle to apply presentation styles.
EXAMPLE The assignment of style information by a styled item and a presentation layer with style. Since the presentation styles are different, IfcCurveStyle and IfcSurfaceStyle, both are applied to the geometric representation item.
![]() |
Figure 281 — Representation item style |
Figure 282 shows in instance diagram explaining the override of IfcPresentationLayerWithStyle by IfcStyledItem to apply presentation styles.
EXAMPLE The assignment of style information by a styled item and a presentation layer with style. Since the presentation styles for curve style are aprovided by both, the IfcCurveStyle provided by the IfcStyledItem overrides the IfcCurveStyle provided by the IfcPresentationLayerWithStyle
![]() |
Figure 282 — Representation item style override |
HISTORY New entity in IFC Release 2x.
IFC2x3 CHANGE The inverse attributes StyledByItem and LayerAssignments have been added. Upward compatibility for file based exchange is guaranteed.
"
5503;IfcMappedItem;"
Definition from ISO/CD 10303-43:1992: A mapped item is the use of an existing representation (the mapping source - mapped representation) as a representation item in a second representation.
NOTE: A mapped item is a subtype of representation item. It enables a representation to be used as a representation item in one or more other representations. The mapped item allows for the definition of a representation using other representations.
The IfcMappedItem is the inserted instance of a source definition (to be compared with a
block / shared cell / macro definition). The instance is inserted by applying a Cartesian transformation operator as the MappingTarget.
EXAMPLE An IfcMappedItem can reuse other mapped items (ako nested blocks), doing so the IfcRepresentationMap is based on an IfcShapeRepresentation including one or more IfcMappedItem's.
NOTE Corresponding ISO 10303 entity: mapped_item. Please refer to ISO/IS
10303-43:1994, for the final definition of the formal standard. The definition of mapping_target (MappingTarget) has been restricted to be of the type cartesian_transformation_operator
(IfcCartesianTransformationOperator).
HISTORY New entity in IFC Release 2x.
Informal Propositions
- A mapped item shall not be self-defining by participating in the definition of the representation being mapped.
- The dimensionality of the mapping source and the mapping target has to be the same, if the mapping source is a geometric representation item.
"
5506;IfcRepresentationMap;"
Definition from ISO/CD 10303-43:1992: A representation map is the identification of a representation and a representation item in that representation for the purpose of mapping. The representation item defines the origin of the mapping. The representation map is used as the source of a mapping by a mapped item.
NOTE Corresponding ISO 10303 entity: representation_map. Please refer to ISO/IS 10303-43:1994, for the final definition of the formal standard. The following changes have been made: The mapping_origin (MappingOrigin) is constrained to be of type axis2_placement (IfcAxis2Placement).
An IfcRepresentationMap defines the base definition (also referred to as block, cell or macro) called MappedRepresentation within the MappingOrigin. The MappingOrigin defines the coordinate system in which the MappedRepresentation is defined.
The RepresentationMap is used through an IfcMappeditem in one or several IfcShapeRepresentation's. An Cartesian transformation operator can be applied to transform the MappedRepresentation into the placement coordinate system of the shape representation. The transformation of the representation map is restricted to be a Cartesian transformation mapping (translation, rotation, mirroring and scaling).
NOTE The definition of a mapping which is used to specify a new representation item comprises a representation map and a mapped item entity. Without both entities, the mapping is not fully defined. Two entities are specified to allow the same source representation to be mapped into multiple new representations.
HISTORY New entity in IFC Release 2x.
"
5511;IfcCartesianTransformationOperator;"
Definition from ISO/CD 10303-42:1992: A Cartesian transformation operator defines a geometric transformation composed of translation, rotation, mirroring and uniform scaling. The list of normalized vectors u defines the columns of an orthogonal matrix T. These vectors are computed, by the base axis function, from the direction attributes axis1, axis2 and, in Cartesian transformation operator 3d, axis3. If |T|= -1, the transformation includes mirroring. The local origin point A, the scale value S and the matrix T together define a transformation.
The transformation for a point with position vector P is defined by
P -> A + STP
The transformation for a direction d is defined by
d -> Td
The transformation for a vector with orientation d and magnitude k is
defined by
d -> Td, and
k -> Sk
For those entities whose attributes include an axis2 placement, the
transformation is applied, after the derivation, to the derived attributes p
defining the placement coordinate directions. For a transformed surface, the
direction of the surface normal at any point is obtained by transforming the
normal, at the corresponding point, to the original surface. For geometric
entities with attributes (such as the radius of a circle) which have the
dimensionality of length, the values will be multiplied by S.
For curves on surface the p curve.reference to curve will be unaffected
by any transformation. The Cartesian transformation operator shall only be
applied to geometry defined in a consistent system of units with the same units
on each axis. With all optional attributes omitted, the transformation defaults
to the identity transformation. The Cartesian transformation operator shall
only be instantiated as one of its subtypes.
NOTE: Corresponding ISO 10303 entity: cartesian_transformation_operator, please refer to ISO/IS 10303-42:1994, p. 32 for the final definition of the formal standard.
HISTORY: New entity in IFC Release 2x.
"
5521;IfcCartesianTransformationOperator2D;"
Definition from ISO/CD 10303-42:1992: A Cartesian transformation operator 2d defines a geometric transformation in two-dimensional space composed of translation, rotation, mirroring and uniform scaling. The list of normalized vectors u defines the columns of an orthogonal matrix T. These vectors are computed from the direction attributes axis1 and axis2 by the base axis function. If |T|= -1, the transformation includes mirroring.
NOTE: Corresponding ISO 10303 entity : cartesian_transformation_operator_2d, please refer to ISO/IS 10303-42:1994, p. 36 for the final definition of the formal standard.
HISTORY: New entity in IFC Release 2x.
"
5527;IfcCartesianTransformationOperator2DnonUniform;"
A Cartesian transformation operator 2d non uniform defines a geometric transformation in two-dimensional space composed of translation, rotation, mirroring and non uniform scaling. Non uniform scaling is given by two different scaling factors:
- SELF\IfcCartesianTransformationOperator.Scale: the x axis scale factor
- Scale2: the y axis scale factor
If the Scale factor (at supertype IfcCartesianTransformationOperator) is omitted, it defaults to 1.0. If the Scale2 factor is omitted, it defaults to the value of Scale (the x axis scale factor).
NOTE: The scale factor (Scl) defined at the supertype IfcCartesianTransformationOperator is used to express the calculated Scale factor (normally x axis scale factor).
HISTORY: New entity in IFC Release 2x.
"
5531;IfcDirection;"
Definition from ISO/CD 10303-42:1992: This entity defines a general direction vector in two or three dimensional space. The actual magnitudes of the components have no effect upon the direction being defined, only the ratios X:Y:Z or X:Y are significant.
NOTE: The components of this entity are not normalized. If a unit vector is required it should be normalized before use.
NOTE: Corresponding ISO 10303 entity: direction. Please refer to ISO/IS 10303-42:1994, p.26 for the final definition of the formal standard. The derived attribute Dim has been added (see also note at IfcGeometricRepresentationItem).
HISTORY: New entity in IFC Release 1.0
"
5534;IfcCartesianTransformationOperator3D;"
Definition from ISO/CD 10303-42:1992: A Cartesian transformation operator 3d defines a geometric transformation in three-dimensional space composed of translation, rotation, mirroring and uniform scaling. The list of normalized vectors u defines the columns of an orthogonal matrix T. These vectors are computed from the direction attributes axis1, axis2 and axis3 by the base axis function. If |T|= -1, the transformation includes mirroring.
NOTE: Corresponding ISO 10303 entity: cartesian_transformation_operator_3d, please refer to ISO/IS 10303-42:1994, p. 33 for the final definition of the formal standard.
HISTORY: New entity in IFC Release 2x.
"
5542;IfcCartesianTransformationOperator3DnonUniform;"
A Cartesian transformation operator 3d non uniform defines a geometric transformation in three-dimensional space composed of translation, rotation, mirroring and non uniform scaling. Non uniform scaling is given by three different scaling factors:
- SELF\IfcCartesianTransformationOperator.Scale: the x axis scale factor
- Scale2: the y axis scale factor
- Scale3: the z axis scale factor
If the Scale factor (at supertype IfcCartesianTransformationOperator) is omitted, it defaults to 1.0. If the Scale2 or the Scale3 factor is omitted, it defaults to the value of Scale (the x axis scale factor).
NOTE: The scale factor (Scl) defined at the supertype IfcCartesianTransformationOperator is used to express the calculated Scale factor (normally x axis scale factor).
HISTORY: New entity in IFC Release 2x.
"
5549;IfcCartesianPoint;"
Definition from ISO/CD 10303-42:1992: A point defined by its coordinates in a two or three dimensional rectangular Cartesian coordinate system, or in a two dimensional parameter space. The entity is defined in a two or three dimensional space.
The derived attribute Dim has been added (see also note at IfcGeometricRepresentationItem). The WR1 was added to constrain the usage of IfcCartesianPoint in the context of IFC geometry. For the purpose of defining geometry in IFC only two and three dimensional Cartesian points are used.
NOTE: Corresponding STEP entity: cartesian_point, please refer to ISO/IS 10303-42:1994, p. 23 for the final definition of the formal standard.
HISTORY: New entity in IFC Release 1.0
"
5553;IfcPoint;"
Definition from ISO/CD 10303-42:1992: A point is a location in some real Cartesian coordinate space Rm, for m = 1, 2 or 3.
NOTE: Corresponding ISO 10303 entity: point. Only the subtypes cartesian_point, point_on_curve, point_on_surface have been incorporated in the current release of IFC. Please refer to ISO/IS 10303-42:1994, p. 22 for the final definition of the formal standard.
HISTORY: New entity in IFC Release 1.5
"
5557;IfcPointOnCurve;"
Definition from ISO/CD 10303-42:1992: A point on curve is a point which lies on a curve. The point is determined by evaluating the curve at a specific parameter value. The coordinate space dimensionality of the point is that of the basis curve.
NOTE: Corresponding STEP entity: point_on_curve. Please refer to ISO/IS 10303-42:1994, p. 23 for the final definition of the formal standard.
HISTORY: New entity in Release IFC2x Edition 2.
Informal Propositions:
- The value of the point parameter shall not be outside the parametric range of the curve.
"
5561;IfcCurve;"
Definition from ISO/CD 10303-42:1992: A curve can be envisioned as the path of a point moving in its coordinate space.
NOTE: Corresponding ISO 10303 entity: curve, only the following subtypes have been incorporated into IFC: line as IfcLine, conic as IfcConic, bounded_curve as IfcBoundedCurve. Please refer to ISO/IS 10303-42:1994, p.37 for the final definition of the formal standard. The derived attribute Dim has been added (see also note at IfcGeometricRepresentationItem).
HISTORY: New entity in IFC Release 1.0
Informal proposition:
- A curve shall be arcwise connected
- A curve shall have an arc length greater than zero.
"
5569;IfcBoundedCurve;"
Definition from ISO/CD 10303-42:1992: A bounded curve is a curve of finite arc length with identifiable end points.
NOTE Corresponding ISO 10303 name: bounded_curve, only the following subtypes have been incorporated into IFC: polyline as IfcPolyline, trimmed_curve as IfcTrimmedCurve, composite_curve as IfcCompositeCurve. Please refer to ISO/IS 10303-42:1994, p.44 for the final definition of the formal standard.
HISTORY New class in IFC Release 1.0
Informal propositions:
- A bounded curve has finite arc length.
- A bounded curve has a start point and an end point.
"
5574;IfcCompositeCurve;"
Definition from ISO/CD 10303-42:1992: A composite
curve is a collection of curves joined end-to-end. The
individual segments of the curve are themselves defined as
composite curve segments. The parameterization of the
composite curve is an accumulation of the parametric ranges
of the referenced bounded curves. The first segment is
parameterized from 0 to
l1 and for i
≤ 2, the
ith segment is
parameterized from:
![]()
where lk is the parametric
length (i.e., difference between maximum and minimum
parameter values) of the curve underlying the
kth segment.
Let T denote the parameter for the composite curve.
Then, if the ith segment is not a reparameterised
composite curve segment, T is related to the
parameter ti; ti0
≤ ti ≤
ti1; for the ith segment by the
equation:
![]()
if Segments[i].SameSense =
TRUE;
or by the equation:
![]()
if Segments[i].SameSense =
FALSE;
If the segments[i] is of type reparameterised composite
curve segment,
![]()
where τ is defined at
reparameterized composite curve segment (see
IfcReparameterizedCompositeCurveSegment).
Figure 279 illustrates an example of a composite curve.
![]() |
Figure 279 — Composite curve |
Consider an IfcCompositeCurve having line segment and an arc segment. The line should be parameterized:
- IfcPolyline with start= 0.,0. end= 0.,1., SameSense= TRUE, parametric length = 1.
The arch should be parameterized:
- IfcTrimmedCurve with start= 180', end= 90', SameSense= FALSE, parametric length = 90.
Then the parameterization of the composite curve is:
- IfcCompositeCurve with 0. ≤ T ≤ 1. (line segment) and 1. ≤ T ≤ 91. (arc segment), parametric length = 91.
NOTE Corresponding ISO 10303 entity: composite_curve, please refer to ISO/IS 10303-42:1994, p. 56 for the final definition of the formal standard. The WR2 is added to ensure consistent Dim at all segments.
HISTORY New class in IFC Release 1.0
Informal Propositions:
- The SameSense attribute of each segment
correctly specifies the senses of the component curves.
When traversed in the direction indicated by
SameSense, the segments shall join end-to-end.
"
5582;IfcCompositeCurveOnSurface;"
Definition from ISO/CD 10303-42:1992 A composite curve on surface is a collection of segments which are curves on a surface. Each segment shall lie on the basis surface.
There shall be at least positional continuity between adjacent segments. The parameterization of the composite curve is obtained from the accumulation of the parametric ranges of the segments. The first segment is parameterized from 0 to l1, and, for i ≥ 2, the ith segment is parameterized from
![]()
where lk is the parametric length (that is, the difference between maximum and minimum parameter values) of the kth curve segment.
The IfcCompositeCurveOnSurface is a collection of segments, based on p-curves. i.e. a curve which lies on the basis of a surface and is defined in the parameter space of that surface. The p-curve segment is a special type of a composite curve segment and shall only be used to bound a surface.
NOTE Corresponding ISO 10303 entity: composite_curve_on_surface. Please refer to ISO/IS 10303-42:1994, p.64 for the final definition of the formal standard.
HISTORY New entity in IFC2x4.
"
5586;IfcBoundaryCurve;"
Definition from ISO/CD 10303-42:1992˙ A boundary curve
is a type of bounded curve suitable for the definition of a
surface boundary.
NOTE˙ Corresponding ISO 10303 entity: boundary_curve. Please refer to ISO/IS 10303-42:1994, p.89 for the final definition of the formal standard.
HISTORY˙ New entity in IFC2x4.
"
5589;IfcOuterBoundaryCurve;"
Definition from ISO/CD 10303-42:1992˙ This is a special subtype of boundary curve which has the additional semantics of defining an outer boundary of a surface. No more than one such curve shall be included in the set of boundaries of a curve bounded surface.
NOTE˙ Corresponding ISO 10303 entity: outer_boundary_curve. Please refer to ISO/IS 10303-42:1994, p.89 for the final definition of the formal standard.
HISTORY˙ New entity in IFC2x4.
"
5590;IfcSurface;"
Definition from ISO/CD 10303-42:1992: A surface can be envisioned as a set of connected points in 3-dimensional space which is always locally 2-dimensional, but need not be a manifold.
NOTE Corresponding ISO 10303 entity: surface, the following subtypes have been incorporated into IFC - elementary_surface (as IfcElementarySurface), swept_surface (as IfcSweptSurface) and bounded_surface (as IfcBoundedSurface). Please refer to ISO/IS 10303-42:1994, p. 68 for the final definition of the formal standard.
HISTORY New class in IFC Release 1.5
Informal proposition:
- A surface has non zero area.
- A surface is arcwise connected.
"
5595;IfcElementarySurface;"
Definition from ISO/CD 10303-42:1992: An elementary surface (IfcElementarySurface) is a simple analytic surface with defined parametric representation.
NOTE Corresponding ISO 10303 entity: elementary_surface. Only the subtype plane is incorporated as IfcPlane. The derived attribute Dim has been added (see also note at IfcGeometricRepresentationItem). Please refer to ISO/IS 10303-42:1994, p. 69 for the final definition of the formal standard.
HISTORY New class in IFC Release 1.5
"
5599;IfcPlane;"
Definition from ISO/CD 10303-42:1992: A plane is an unbounded surface with a constant normal. A plane is defined by a point on the plane and the normal direction to the plane. The data is to be interpreted as follows:
C = Position.Location
x = Position.P[1]
y = Position.P[2]
z = Position.P[3] => normal to plane
and the surface is parameterized as:
![]()
where the parametric range is -∞ < u,v <
∞. In the above parameterization the length unit for the
unit vectors x and y is derived from the context of
the plane.
The planar surface is an unbounded surface in the direction of x and y. Bounded planar surfaces are defined by using a subtype of IfcBoundedSurface with BasisSurface being a plane.
NOTE A rectangular bounded planar surface can
be defined by an IfcRectangularTrimmedSurface with
BasisSurface being the plane and U1 = left bound in
x, U2 = right bound in x, V1 = lower
bound in y, V2 = upper bound in y if viewed
into the direction of the negative normal. (assuming the
Usense and Vsense agree to the sense of the basis
surface).
The inherited attributes are interpreted as
- SELF\IfcElementarySurface.Position defines the
location and orientation of the planar surface.
- SELF\IfcElementarySurface.Position.Location defines a
point on the planar surface.
- SELF\IfcElementarySurface.Position.P[3] defines the
normal of the planar surface.
NOTE Corresponding ISO 10303 entity: plane. Please refer to ISO/IS 10303-42:1994, p.69 for the final definition of the formal standard.
HISTORY New class in IFC Release 1.5
"
5600;IfcCylindricalSurface;"
Definition from ISO/CD 10303-42:1992: A cylindrical surface is a surface at a constant distance (the radius) from a straight line. A cylindrical surface is defined by its radius and its orientation and location. The data is to be interpreted as follows:
C = Position.Location
x = Position.P[1]
y = Position.P[2]
z = Position.P[3]
R = Radius
and the surface is parameterized as:
![]()
where the parametric range is -∞ < u,v <
∞ .
In the above parameterization the length unit for the unit
vectors z is equal to that of the radius R.
In the placement coordinate system defined above, the surface is
represented by the equation S = 0, where
![]()
The positive direction of the normal to the surface at any
point on the surface is given by
![]()
, or as unit normal by
![]()
The direction of the normal is away from the axis of the cylinder.
The cylindrical surface is a surface unbounded in the direction of z. Bounded cylindrical surfaces are defined by using a subtype of IfcBoundedSurface with BasisSurface being a cylindrical surface.
NOTE A bounded cylindrical surface can be
defined by an IfcRectangularTrimmedSurface with
BasisSurface being the cylindrical surface and U1 =
0°, U2 = 360° and V1 = lower bound in
z, V2 = upper bound in z (if the plane angle
measure is degree). A bounded cylindrical arc surface is provided
with |U1 - U2| < 360° (assuming the Usense and Vsense
agree to the sense of the basis surface).
NOTE A non-rectangular bounded cylindrical
surface, e.g. the surface of a round wall underneath a sloped
roof, cab be defined by an IfcCurveBoundedSurface with
IfcBoundaryCurve's, being a collection of p-curve
segments. A p-curve is curve which lies on the basis of a surface
and is defined in the parameter space of that
surface.
The inherited attributes are interpreted as
- SELF\IfcElementarySurface.Position defines the
location and orientation of the cylindrical surface.
- SELF\IfcElementarySurface.Position.Location definesd a
point on the axis of the cylindrical surface.
- SELF\IfcElementarySurface.Position.P[3] defines the
direction of the axis of the cylindrical surface.
NOTE Corresponding ISO 10303 entity: plane. Please refer to ISO/IS 10303-42:1994, p.70 for the final definition of the formal standard.
HISTORY New class in IFC2x4.
"
5602;IfcAxis2Placement3D;"
Definition from ISO/CD 10303-42:1992: The location and orientation in three dimensional space of three mutually perpendicular axes. An axis2_placement_3D is defined in terms of a point (inherited from placement supertype) and two (ideally orthogonal) axes. It can be used to locate and originate an object in three dimensional space and to define a placement coordinate system. The entity includes a point which forms the origin of the placement coordinate system. Two direction vectors are required to complete the definition of the placement coordinate system. The axis is the placement Z axis direction and the ref_direction is an approximation to the placement X axis direction.
If the attribute values for Axis and RefDirection
are not given, the placement defaults to P[1] (x-axis) as [1.,0.,0.],
P[2] (y-axis) as [0.,1.,0.] and P[3] (z-axis) as [0.,0.,1.].
NOTE Corresponding ISO 10303 name: axis2_placement_3d, please refer to ISO/IS 10303-42:1994 for the final definition of the formal standard. The WR5 is added to ensure that either both attributes Axis and RefDirection are given, or both are omitted.
HISTORY New entity in IFC Release 1.5.
Figure 276 illustrates the definition of the IfcAxis2Placement3D within the three-dimensional coordinate system.
![]() |
Figure 276 — Axis2 placement 3D |
"
5611;IfcSweptSurface;"
Definition from ISO/CD 10303-42:1992: A swept surface is one that is constructed by sweeping a curve along another curve.
NOTE: Corresponding ISO 10303 entity: swept_surface. Please refer to ISO/IS 10303-42:1994, p.76 for the final definition of the formal standard.
HISTORY: New entity in IFC Release 2x.
"
5618;IfcSurfaceOfRevolution;"
Definition from ISO/CD 10303-42:1992: A surface of revolution (IfcSurfaceOfRevolution) is the surface obtained by rotating a curve one complete revolution about an axis. The data shall be interpreted as below.
The parameterization is as follows where the curve has a parameterization l(u):
C = AxisPosition.Location
V = AxisPosition.Z
![]()
In order to produce a single-value surface the a complete revolution, the curve shall be such that when expressed in a cylindrical coordinate system the curve shall be such that when expressed in a cylindrical coordinate system (r,φ ,z) centred at C with an axis V no two distinct parametric points on the curve shall have the same values for (r, z).
For a surface of revolution the parametric range is 0 < u < 360 degree. The parameterization range for v is defined by referenced curve.
NOTE: Corresponding ISO 10303 entity: surface_of_revolution. Please refer to ISO/IS 10303-42:1994, p.76 for the final definition of the formal standard.
HISTORY: New entity in IFC2x.
Informal propositions:
- The surface shall not self-intersect
- The swept curve shall not be coincident with the axis line for any finite part of its legth.
"
5621;IfcAxis1Placement;"
Definition from ISO/CD 10303-42:1992: The direction and location in three dimensional space of a single axis. An axis1_placement is defined in terms of a locating point (inherited from placement supertype) and an axis direction: this is either the direction of axis or defaults to (0.0,0.0,1.0). The actual direction for the axis placement is given by the derived attribute z (Z).
NOTE Corresponding ISO 10303 name: axis1_placement, please refer to ISO/IS 10303-42:1994, p. 28 for the final definition of the formal standard.
HISTORY New entity in IFC Release 1.5
Figure 274 illustrates the definition of the IfcAxis1Placement within the three-dimensional coordinate system.
![]() |
Figure 274 — Axis1 placement |
"
5626;IfcLine;"
Definition from ISO/CD 10303-42:1992: A line is an unbounded curve with constant tangent direction. A line is defined by a point and a direction. The positive direction of the line is in the direction of the Dir vector. The line is parameterized as follows:
P = Pnt
V = Dir
λ(u) = P + uV
and the parametric range is:
∞ < u < ∞
NOTE Corresponding ISO 10303 entity: line. Please refer to ISO/IS 10303-42:1994, p.37 for the final definition of the formal standard. The derived attribute Dim has been added at this level and was therefore demoted from the geometric_representation_item.
HISTORY New class in IFC Release 1.0
"
5630;IfcVector;"
Definition from ISO/CD 10303-42:1992: The vector is defined in terms of the direction and magnitude of the vector. The value of the magnitude attribute defines the magnitude of the vector.
NOTE: The magnitude of the vector can not be reliable calculated from the components of the Orientation attribute. This form of representation was selected to reduce problems with numerical instability. For example a vector of magnitude 2.0 mm and equally inclined to the coordinate axes could be represented with Orientation attribute of (1.0,1.0,1.0).
NOTE: Corresponding ISO 10303 entity: vector. Please refer to ISO/IS 10303-42:1994, p.27 for the final definition of the formal standard. The derived attribute Dim has been added (see also note at IfcGeometricRepresentationItem).
HISTORY: New entity in IFC Release 1.0
"
5635;IfcSurfaceOfLinearExtrusion;"
Definition from ISO/CD 10303-42:1992: This surface is a simple swept surface or a generalized cylinder obtained by sweeping a curve in a given direction. The parameterization is as follows where the curve has a parameterization l(u):
V = ExtrusionAxis
![]()
The parameterization range for v is -¥ < v < ¥ and for u it is defined by the curve parameterization.
NOTE: Corresponding ISO 10303 entity: surface_of_linear_extrusion. Please refer to ISO/IS 10303-42:1994, p.76 for the final definition of the formal standard. The following adaption has been made. The ExtrusionAxis and the Direction are defined as two separate attributes in correlation to the definition of the extruded_area_solid, and not as a single vector attribute. The vector is derived as ExtrusionAxis.
HISTORY: New entity in IFC Release 2x.
Informal propositions:
- The surface shall not self-intersect
"
5640;IfcBoundedSurface;"
Definition from ISO/CD 10303-42:1992: A bounded surface is a surface of finite area with identifiable boundaries.
NOTE Corresponding ISO 10303 name: bounded_surface. Please refer to ISO/IS 10303-42:1994, p.78 for the final definition of the formal standard.
HISTORY New entity in IFC Release 2x
IFC2x4 CHANGE Entity made abstract.
Informal propositions:
- A bounded surface has finite non-zero surface area.
- A bounded surface has boundary curves.
"
5645;IfcCurveBoundedPlane;"
Definition from ISO/CD 10303-42:1992: The curve bounded surface is a parametric surface with curved boundaries defined by one or more boundary curves. The bounded surface is defined to be the portion of the basis surface in the direction of N x T from any point on the boundary, where N is the surface normal and T the boundary curve tangent vector at this point. The region so defined shall be arcwise connected.
The IfcCurveBoundedPlane is a specialized bounded surface class that deals only with bounding basis plane surfaces. The definition varies from STEP as outer and inner boundaries are separated attributes and refer to IfcCurve. The only basis surface that is allowed is of type IfcPlane, and the implicit_outer attribute has not been incorporated, since only unbounded surfaces are used as basis surface.
The BasisSurface is an IfcPlane that establishes the position coordinate system by SELF\IfcElementarySurface.Position. The OuterBoundary and the InnerBoundaries (if provided) shall lie on the surface of IfcPlane. Therefore the IfcCurve's establishing the outer and inner boundaries shall be:
- either a 2D curve within the XY plane of the position coordinate sytem of IfcPlane
- or a 3D curve with all coordinates having a z value = 0.
NOTE Corresponding ISO 10303 entity curve_bounded_surface has been changed to meet the specific requirements of an easy representation of curve bounded planes.
HISTORY New entity in IFC Release 1.5
IFC2x PLATFORM CHANGE: The data type of the attribute OuterBoundary and InnerBoundaries has been changed from Ifc2DCompositeCurve to its supertype IfcCurve with upward compatibility for file based exchange.
"
5649;IfcRectangularTrimmedSurface;"
Definition from ISO/CD 10303-42:1992: The trimmed surface is a simple bounded surface in which the boundaries are the constant parametric lines u1 = u1, u2 = u2, v1 = v1 and v2 = v2. All these values shall be within the parametric range of the referenced surface. Cyclic properties of the parameter range are assumed.
NOTE 1 For example, 370 degrees is equivalent to 10 degrees, for those surfaces whose parametric form is defined using circular functions (sine and cosine).
The rectangular trimmed surface inherits its parameterization directly from the basis surface and has parameter ranges from 0 to |u2 - u1| and 0 to|v2-v1|.
NOTE 2 If the surface is closed in a given parametric direction, the values of u2 or v2 may require to be increased by the cyclic range.
NOTE Corresponding ISO 10303 name: rectangular_trimmed_surface. Please refer to ISO/IS 10303-42:1994, p.86 for the final definition of the formal standard.
HISTORY New class in IFC Release 2x.
Informal propositions:
- The domain of the trimmed surface shall be within the domain of the surface being trimmed.
"
5661;IfcCurveBoundedSurface;"
Definition from ISO/CD 10303-42:1992 The curve bounded surface is a parametric surface with curved boundaries defined by one or more boundary curves. One of the boundary curves may be the outer boundary; any number of inner boundaries is permissible. The region of the curve bounded surface in the basis surface is defined to be the portion of the basis surface in the direction of N x T from any point on the boundary, where N is the surface normal and T the boundary curve tangent vector at this point. The region so defined shall be arcwise connected.
The IfcCurveBoundedSurface is a parametric surface with boundaries defined by p-curves, that is, a curve which lies on the basis of a surface and is defined in the parameter space of that surface. The p-curve is a special type of a composite curve segment and shall only be used to bound a surface.
The outer boundary shall be either defined by:
- an IfcOuterBoundaryCurve, a closed composite curve on surface for the definition of an outer boundary, then the attribute ImplicitOuter has to be set to FALSE, or
- by the implicit boundary of the bounded surface, e.g. the u1, u2, v1, v2 of IfcRectangularTrimmedSurface< then the attribute ImplicitOuter has to be set to TRUE.
Note that some surfaces, like
IfcCylindricalSurface does not have identifiable implicit
boundaries.
NOTE Corresponding STEP entity: curve_bounded_surface. Please refer to ISO/IS 10303-42:1994, p.87 for the final definition of the formal standard.
HISTORY New entity in IFC2x4.
Informal Propositions
- Each curve in the set of Boundaries shall be closed.
- No two curves in the set of Boundaries shall intersect.
- At most one of the boundary curves may enclose any other boundary curve. If an IfcOuterBoundaryCurve is designated, only that curve may enclose any other boundary curve.
"
5665;IfcBSplineSurface;"
Definition from ISO/CD 10303-42:1992: A b_spline_surface is a general form of rational or polynomial parametric surface which is represented by control points, basis functions, and possibly, weights. As with the corresponding curve entity it has some special subtypes where some of the data can be derived.
- The symbology used here is:
| K1 |
= upper_index_on_u_control_points |
| K2 |
= upper_index_on_v_control_points |
| Pij |
= control_points |
| wij |
= weights |
| d1 |
= u_degree |
| d2 |
= v_degree |
- The control points are ordered as
P00, P01, P02,
......, PK1(K2-1),
PK1K2
The weights, in the case of the rational subtype, are ordered
similarly.
- For each parameter, s = u or v, if
k is the upper index on the control points and d is
the degree for s, the knot array is an array of (k
+ d + 2) real numbers [s-d, ....,
sk+1], such that for all indices j in
[-d, k]; sj ≤
sj+1. This array is obtained from the
appropriate u_knots or v_knots list by repeating each multiple
knot according to the multiplicity.
Nid, the ith
normalised B-spline basis function of degree d, is defined
on the subset [si-d, ....,
si+1] of this array.
- Let L denote the number of distinct values amongst the
knots in the knot list; L will be referred to as the
‘upper index on knots’. Let
mj denote the multiplicity (i.e., number
of repetitions) of the jth distinct knot value. Then:
![]()
All knot multiplicities except the first and the last shall be in
the range 1, ...., d; the first and last may have a
maximum value of d+1. In evaluating the basis functions, a
knot u of, e.g., multiplicity 3 is interpreted as a
sequence u, u, u, in the knot array.
- The surface form is used to identify specific quadric surface
types (which shall have degree two), ruled surfaces and surfaces
of revolution. As with the b-spline curve, the surface form is
informational only and the spline data takes precedence.
- The surface is to be interpreted as follows: In the
polynomial case the surface is given by the equation:
![]()
In the rational case the surface equation is:
![]()
NOTE Corresponding ISO 10303 entity: b_spline_surface. Please refer to ISO/IS 10303-42:1994, p. 78 for the final definition of the formal standard.
HISTORY New entity in IFC2x4.
"
5679;IfcBSplineSurfaceWithKnots;"
Definition from ISO 10303:42:1994: This is a B-spline surface in which the knot values are explicitly given. This subtype shall be used to represent non-uniform B-spline surfaces, and may also be used for other knot types.
All knot multiplicities except the first and the last shall be in the range 1,....,d; the first and last may have a maximum value of d + 1. In evaluating the basis functions, a knot u of, e.g., multiplicity 3 is interpreted as a sequence u, u, u, in the knot array.
NOTE Corresponding ISO 10303 entity: b_spline_surface_with_knots. Please refer to ISO/IS 10303-42:1994, p. 81 for the final definition of the formal standard.
HISTORY New entity in IFC2x4.
"
5692;IfcRationalBSplineSurfaceWithKnots;"
A rational B-spline surface with knots is a piecewise parametric rational surface described in terms of control points, and associated weight values.
The surface is to be interpreted as follows:
σ![]()
NOTE: The IfcRationalBSplineSurfaceWithKnots is an entity that had been adopted from ISO 10303, Industrial automation systems and integration — Product data representation and exchange, Part 42: Integrated generic resource: Geometric and topological representation.
NOTE: The specific subtype IfcRationalBSplineSurfaceWithKnots has been introduced to avoid the complexity of ANDOR subtype relationships in the ISO 10303-42 specification
NOTE: Corresponding ISO 10303 entity: rational_b_spline_surface. Please refer to ISO/IS 10303-42:1994, p. 85 for the final definition of the formal standard.
HISTORY: New entity in IFC2x4.
"
5716;IfcCompositeCurveSegment;"
Definition from ISO/CD 10303-42:1992: A composite curve segment is a bounded curve together with transition information which is used to construct a composite curve (IfcCompositeCurve).
The derived attribute Dim has been added (see also note at IfcGeometricRepresentationItem). The IfcCompositeCurveSegment is a subtype of IfcGeometricRepresentationItem (whereas in ISO 10303-42 composite_curve_segment is not a subtype of geometric_representation_item, the proposed 2nd edition of ISO 10303-42 however proposes the subtype relationship).
NOTE Corresponding ISO 10303 entity: composite_curve_segment. Please refer to ISO/IS 10303-42:1994, p.57 for the final definition of the formal standard.
HISTORY New class in IFC Release 1.0
"
5724;IfcReparametrisedCompositeCurveSegment;"
Definition from ISO/CD 10303-42:1992: The
reparametrised composite curve segment is a special type of
composite curve segment which provides the capability to
re-define its parametric length without changing its
geometry.
Let l = ParamLength.
If t0 ≤ t ≤
t1 is the parameter range of
ParentCurve, the new parameter . for the
reparametrised composite curve segment is given by the
equation:
![]()
if SameSense = TRUE;
or by the equation:
![]()
if SameSense = FALSE;
NOTE Corresponding STEP entity: reparametrised_composite_curve_segment. Please refer to ISO/IS 10303-42:1994, p.59 for the final definition of the formal standard.
HISTORY New class in IFC2x4
"
5732;IfcPolyline;"
Definition from ISO/CD 10303-42:1992: A polyline
is a bounded curve of n - 1 linear segments, defined by a
list of n points, P1, P2 ... Pn.
The ith segment of the curve is parameterized as follows:
![]()
for 1 ≤ i ≤ n - 1
where i - 1 ≤ u ≤ i and
with parametric range of 0 <≤ u ≤ n - 1.
NOTE Corresponding ISO 10303 entity: polyline. Please refer to ISO/IS 10303-42:1994, p. 45 for the final definition of the formal standard.
HISTORY New class in IFC Release 1.0
"
5735;IfcTrimmedCurve;"
Definition from ISO/CD 10303-42:1992:
A trimmed curve is a bounded curve which is created by taking a selected
portion, between two identified points, of the associated basis curve.
The basis curve itself is unaltered and more than one trimmed curve may
reference the same basis curve. Trimming points for the curve may be
identified by:
- parametric value
- geometric
position
- both of the above
At least one of these shall be specified at each
end of the
curve. The SenseAgreement makes it possible to
unambiguously define any segment of a closed curve such as a circle.
The combinations of sense and ordered end points make it possible to
define four distinct directed segments connecting two different points
on a circle or other closed curve. For this purpose cyclic properties
of the parameter range are assumed; for example, 370 degrees is
equivalent to 10 degrees.
The IfcTrimmedCurve has a parameterization
which is inherited from the particular basis curve reference. More
precisely the parameter s of the trimmed curve is derived from the
parameter of the basis curve as follows:
- if SenseAgreement is TRUE: s
= t - t1
- if SenseAgreement
is FALSE: s
= t2 - t
In the above equations t1 is
the value
given by Trim1 or the parameter value corresponding
to point 1 and t2 is the value given by Trim2
or the parameter value corresponding to point 2. The resultant IfcTrimmedCurve
has a parameter ranging from 0 at the first trimming point to |t2
- t1| at the second trimming point.
NOTE In case
of a closed curve,
it may be necessary to increment t1 or t2 by the parametric length for
consistency with the sense flag.
NOTE Corresponding ISO 10303 entity: trimmed_curve; As a further IFC restriction, an IfcTrimmedCurve should only trim a IfcLine or IfcConic. Please refer to ISO/IS 10303-42:1994, p. 54 for the final definition of the formal standard.
HISTORY New class in IFC Release 1.0
Informal Propositions:
- Where both the parameter value and the Cartesian
point
exist for Trim1 and Trim2 they
shall be consistent. (i.e., the BasisCurve
evaluated at the parameter value shall coincide with the specified
point).
- When a Cartesian point is specified by Trim1
or by Trim2 it shall lie on the BasisCurve.
- Except the case of a closed BasisCurve
where both parameter 1 and parameter 2 exist, they shall be consistent
with the sense flag, i.e., (sense = parameter 1 < parameter 2). Or, for every open curve where both
parameter 1 and parameter 2 exist, they shall be consistent with the SenseAgreement,
i.e., SenseAgreement = (parameter 1 <
parameter 2).
- If both parameter 1
and parameter 2 exist, then parameter 1
<> parameter 2. For a
closed base curve, e.g. IfcCircle or IfcEllipse,
this also applies to the cyclic properties, as 360' is equal to 0',
parameter 1 = 360' and parameter 2 = 0' are treated as being equal and
therefore violating this proposition.
- When
a parameter value is specified by Trim1
or Trim2 it shall lie within the parametric range
of the BasisCurve.
Additional illustration from IAI:
![]() |
The
figure above shows the four arcs (dashed blue and
green lines with arrow showing different orientations) that can be
defined by the same BasisCurve (of type IfcCircle)
and the same trimming points (given by Cartesian points and parameter
values) by using different assignments to Trim1 and
Trim2 and SenseAgreement.
Note: Since the BasisCurve is closed (type IfcCircle),
the exception of the informal proposition IP3 applies, i.e. the sense
flag is not
required to be consistent with the parameter values of Trim1
and Trim1, so the rule (sense = parameter 1
< parameter 2) may not be fulfilled. |
"
5751;IfcBSplineCurve;"
Definition from ISO/CD 10303-42:1992: A B-spline curve is a piecewise parametric polynomial or rational curve described in terms of control points and basis functions. The B-spline curve has been selected as the most stable format to represent all types of polynomial or rational parametric curves. With appropriate attribute values it is capable of representing single span or spline curves of explicit polynomial, rational, Bezier or B-spline type.
Interpretation of the data is as follows:
-
All weights shall be positive and the curve is given by
![]()
| k+1 |
= number of control points |
| Pi |
= control points |
| wi |
= weights |
| d |
= degree |
The knot array is an array of (k+d+2) real numbers
[u-d ... uk+1], such that for
all indices j in [-d,k], uj <=
uj+1. This array is obtained from the knot data list by
repeating each multiple knot according to the multiplicity. N
di, the ith normalized B-spline basis function
of degree d, is defined on the subset [ui-d, ... ,
ui+1] of this array.
-
Let L denote the number of distinct values among the
d+k+2 knots in the knot array; L will be referred to as
the 'upper index on knots'. Let mj denote the multiplicity
(number of repetitions) of the jth distinct knot. Then
![]()
All knot multiplicities except the first and the last shall be in
the range 1 ... degree; the first and last may have a maximum value of degree +
1. In evaluating the basis functions, a knot u of e.g. multiplicity 3 is
interpreted as a string u, u, u, in the knot array. The B-spline curve
has 3 special subtypes (Note: only 1, Bezier curve, included in this IFC
release) where the knots and knot multiplicities are derived to provide
simple default capabilities.
- Logical flag is provided to indicate whether the curve self
intersects or not.
Figure 277 (from ISO 10303-42) illustrates a B-spline curve.
![]() |
Figure 277 — B-spline curve |
NOTE Corresponding ISO 10303 entity: b_spline_curve. Please refer to ISO/IS 10303-42:1994, p. 45 for the final definition of the formal standard.
HISTORY New entity in Release IFC2x2.
"
5761;IfcBSplineCurveWithKnots;"
Definition from ISO 10303:42:1994: This is the type of b-spline curve for which the knot values are explicitly given. This subtype shall be used to represent non-uniform B-spline curves and may be used for other knot types.
Let L denote the number of distinct values amongst the
d+k+2 knots in the knot list; L will be
referred to as the ‘upper index on knots’. Let
mj denote the multiplicity (i.e., number of
repetitions) of the jth distinct knot. Then:
![]()
All knot multiplicities except the first and the last shall be
in the range 1,...,d; the first and last may have a
maximum value of d + 1. In evaluating the basis functions,
a knot u of, e.g., multiplicity 3 is interpreted as a
sequence u, u, u,; in the knot array.
NOTE Corresponding ISO 10303 entity: b_spline_curve_with_knots. Please refer to ISO/IS 10303-42:1994, p. 46 for the final definition of the formal standard.
HISTORY New entity in IFC2x4.
"
5769;IfcRationalBSplineCurveWithKnots;"
A rational B-spline curve with knots is a B-spline curve
described in terms of control points and basic functions. It
describes weights in addition to the control points defined at the
supertype IfcBSplineCurve.
NOTE: The
IfcRationalBSplineCurveWithKnots is an entity that had been
adopted from ISO 10303, Industrial automation systems and
integration — Product data representation and exchange, Part
42: Integrated generic resource: Geometric and topological
representation.
NOTE: The specific subtype
IfcRationalBSplineCurveWithKnots has been introduced to
avoid the complexity of ANDOR subtype relationships in the ISO
10303-42 specification
All weights shall be positive and the curve is given by:
![]()
where
| k+1 |
number of control points |
| Pi |
control points |
| wi |
weights |
| d |
degree |
NOTE Corresponding ISO 10303 entity: rational_b_spline_curve. Please refer to ISO/IS 10303-42:1994, p. 45 for the final definition of the formal standard.
HISTORY New entity in IFC2x4.
"
5781;IfcConic;"
Definition from ISO/CD 10303-42:1992: A conic (IfcConic) is a planar curve which could be produced by intersecting a plane with a cone. A conic is defined in terms of its intrinsic geometric properties rather than being described in terms of other geometry. A conic class always has a placement coordinate system defined by a two or three dimensional placement. The parametric representation is defined in terms of this placement coordinate system.
NOTE Corresponding ISO 10303 entity: conic, only the following subtypes have been incorporated into IFC 1.0, 1.5 & 2.0: circle as IfcCircle, ellipse as IfcEllipse. The derived attribute Dim has been added at this level and was therefore demoted from the geometric_representation_item. Please refer to ISO/IS 10303-42:1994, p. 38 for the final definition of the formal standard.
HISTORY New class in IFC Release 1.0
"
5785;IfcCircle;"
Definition from ISO/CD 10303-42:1992: An IfcCircle is defined by a radius and the location and orientation of the circle. Interpretation of data should be as follows:
C = SELF\IfcConic.Position.Location
x = SELF\IfcConic.Position.P[1]
y = SELF\IfcConic.Position.P[2]
z = SELF\IfcConic.Position.P[3]
R = Radius
and the circle is parameterized as
![]()
The parameterization range is 0 £
u £2p (or 0
£u £
360 degree). In the placement coordinate system defined above, the circle is
the equation C = 0, where
![]()
The positive sense of the circle at any point is in the tangent direction, T, to the curve at the point, where
![]()
NOTE A circular arc is defined by using the trimmed curve (IfcTrimmedCurve) entity in conjunction with the circle (IfcCircle) entity as the BasisCurve.
NOTE Corresponding ISO 10303 entity: circle, please refer to ISO/IS 10303-42:1994, p. 38 for the final definition of the formal standard.
HISTORY New class in IFC Release 1.0
Figure 278 illustrates the definition of the IfcCircle within the (in this case three-dimensional) position coordinate system.
![]() |
Figure 278 — Circle geometry |
"
5787;IfcEllipse;"
Definition from ISO/CD 10303-42:1992: An ellipse (IfcEllipse) is a conic section defined by the lengths of the semi-major and semi-minor diameters and the position (center or mid point of the line joining the foci) and orientation of the curve. Interpretation of the data shall be as follows:
C = SELF\IfcConic.Position.Location
x = SELF\IfcConic.Position.P[1]
y = SELF\IfcConic.Position.P[2]
z = SELF\IfcConic.Position.P[3]
R1 = SemiAxis1
R2 = SemiAxis2
and the ellipse is parameterized as:
![]()
The parameterization range is 0 £
u £ 2p (or 0
£ u £
360 degree). In the placement coordinate system defined above, the ellipse is
the equation C = 0, where
![]()
The positive sense of the ellipse at any point is in the tangent direction, T, to the curve at the point, where
![]()
The inherited Position.Location from IfcConic is the center of the IfcEllipse, and the inherited Position.P[1] from IfcConic the direction of the SemiAxis1.
NOTE Corresponding ISO 10303 entity: ellipse. Please refer to ISO/IS 10303-42:1994, p. 39 for the final definition of the formal standard.
HISTORY New class in IFC Release 1.0
Figure 280 illustrates the definition of the IfcEllipse within the (in this case three-dimensional) position coordinate system.
![]() |
Figure 280 — Ellipse geometry |
"
5790;IfcOffsetCurve2D;"
Definition from ISO/CD 10303-42:1992: An offset curve 2d (IfcOffsetCurve2d) is a curve at a constant distance from a basis curve in two-dimensional space. This entity defines a simple plane-offset curve by offsetting by distance along the normal to basis curve in the plane of basis curve. The underlying curve shall have a well-defined tangent direction at every point. In the case of a composite curve, the transition code between each segment shall be cont same gradient or cont same gradient same curvature.
NOTE: The offset curve 2d may differ in nature from the basis curve; the offset of a non self- intersecting curve can be self-intersecting. Care should be taken to ensure that the offset to a continuous curve does not become discontinuous.
The offset curve 2d takes its parameterization from the basis curve. The offset curve 2d is parameterized as
![]()
where T is the unit tangent vector to the basis curve C(u) at parameter value u, and d is distance. The underlying curve shall be two-dimensional.
NOTE Corresponding ISO 10303 entity: offset_curve_2d, Please refer to ISO/IS 10303-42:1994, p.65 for the final definition of the formal standard.
HISTORY New entity in IFC Release 2.x
"
5795;IfcOffsetCurve3D;"
Definition from ISO/CD 10303-42:1992: An offset curve 3d is a curve at a constant distance from a basis curve in three-dimensional space. The underlying curve shall have a well-defined tangent direction at every point. In the case of a composite curve the transition code between each segment shall be cont same gradient or cont same gradient same curvature. The offset curve at any point (parameter) on the basis curve is in the direction V x T where V is the fixed reference direction and T is the unit tangent to the basis curve. For the offset direction to be well defined, T shall not at any point of the curve be in the same, or opposite, direction as V.
NOTE: The offset curve 3d may differ in nature from the basis curve; the offset of a non self- intersecting curve can be self-intersecting. Care should be taken to ensure that the offset to a continuous curve does not become discontinuous.
The offset curve 3d takes its parameterization from the basis curve. The offset curve 3d is parameterized as
![]()
where T is the unit tangent vector to the basis curve C(u) at parameter value u, and d is distance. The underlying curve shall be three-dimensional.
NOTE Corresponding ISO 10303 entity: offset_curve_3d, Please refer to ISO/IS 10303-42:1994, p.66 for the final definition of the formal standard.
HISTORY New entity in IFC Release 2.x
Informal propositions:
- At no point on the curve shall ref direction be parallel, or opposite to, the direction of the tangent vector.
"
5801;IfcPCurve;"
Definition from ISO/CD 10303-42:1992: A pcurve is a curve which lies on the basis of a surface and is defined in the parameter space of that surface. The basis curve is a curve defined in the two-dimensional parametric space of a reference basis surface. Although it is defined by a curve in two dimensional space, the variables involved are u and v, which occur in the parametric representation of the referenced surface, rather than the x, y, Cartesian coordinates.
The basis curve is only defined within the parametric range of the surface.
NOTE Corresponding ISO 10303 entity: pcurve. Please refer to ISO/IS 10303-42:1994, p.59 for the final definition of the formal standard.
The definition of IfcPCurve derivates from pcurve. The following changes have been made: The BasisCurve replaces the definition of reference_to_curve since there is no requirement of having same dimensionality within the representation context.
HISTORY New class in IFC2x4.
"
5805;IfcPointOnSurface;"
Definition from ISO/CD 10303-42:1992: A point on surface is a point which lies on a parametric surface. The point is determined by evaluating the surface at a particular pair of parameter values.
NOTE: Corresponding ISO 10303 entity: point_on_surface. Please refer to ISO/IS 10303-42:1994, p. 24 for the final definition of the formal standard.
HISTORY: New entity in Release IFC2x Edition 2.
Informal Propositions:
- The parametric values specified for u and v shall not be outside the parametric range of the basis surface.
"