Index Page

  Specification for IfcSharedBldgElements  

EXPRESS Definition

EXPRESS-G Diagram

IDL Definition

Schema Semantic Definition

The Schema IfcSharedBldgElements is defined at the Interoperability Layer and covers the definition of building elements that are shared among several IFC domain or application type models.

Type IfcBeamTypeEnum

EXPRESS Definition

Type Semantic Definition

This enumeration defines the available Generic Types for IfcBeam.

Enumeration:

SimpleBeam
CompoundBeam
Truss

NOTE This type is identical with IFC Release 1.0 type IfcBeamTypeEnum

Type IfcBuiltInTypeEnum

EXPRESS Definition

Type Semantic Definition

This enumeration defines the available Generic Types for IfcBuiltIn.

Enumeration:

Cabinet
CounterTop
Railing

NOTE This type is identical with IFC Release 1.0 type IfcBuiltInTypeEnum

Type IfcColumnTypeEnum

EXPRESS Definition

Type Semantic Definition

This enumeration defines the available Generic Types for IfcColumn.

Enumeration:

SimpleColumn
CompoundColumn
Truss

NOTE This type is identical with IFC Release 1.0 type IfcColumnTypeEnum

Type IfcCoveringTypeEnum

EXPRESS Definition

Type Semantic Definition

This enumeration defines the available Generic Types for IfcCovering.

Enumeration:

Ceiling
Flooring
WallCovering

NOTE This is a new type in Release 1.5.

Type IfcDoorTypeEnum

EXPRESS Definition

Type Semantic Definition

This enumeration defines the available Generic Types for IfcDoor.

Enumeration:

SingleSwing
DoubleSwing
Slide
Rollup
Revolving

NOTE This type is identical with IFC Release 1.0 type IfcDoorTypeEnum

Type IfcFloorTypeEnum

EXPRESS Definition

Type Semantic Definition

This enumeration defines the available Generic Types for IfcFloor.

Enumeration:

SolidFloor
LayeredFloor
ElementedFloor

NOTE This type is identical with IFC Release 1.0 type IfcFloorTypeEnum

Type IfcRoofSlabTypeEnum

EXPRESS Definition

Type Semantic Definition

This enumeration defines the available Generic Types for IfcRoofSlab.

Enumeration:

SolidSlab
LayeredSlab
ElementedSlab

NOTE This type is identical with IFC Release 1.0 type IfcRoofSlabTypeEnum

Type IfcWallTypeEnum

EXPRESS Definition

Type Semantic Definition

This enumeration defines the available Generic Types for IfcWall.

Enumeration:

SolidWall
LayeredWall
ElementedWall

NOTE This type is identical with IFC Release 1.0 type IfcWallTypeEnum

Type IfcWindowTypeEnum

EXPRESS Definition

Type Semantic Definition

This enumeration defines the available Generic Types for IfcWindow.

Enumeration:

FixedCasement
Sliding
Awning
DoupleHung
Casement
Pivoting

NOTE This type is identical with IFC Release 1.0 type IfcWindowTypeEnum

Class IfcBeam

EXPRESS Definition

Class Semantic Definition

Definition from IFC: IfcBeam is defined in the Architecture Domain and possibly reused by other domains. It represents a horizontal, or nearly horizontal structural member designed to carry loads.

NOTE This class was IfcBeam in IFC Release 1.0 and has been modified in IFC Release 1.5

ISSUE See issues I-330, I-365 for changes made in IFC Release 1.5.1

Attribute and Relationship Definitions

Inherited Classes

Formal Propositions:

WR61	Only IfcPropertyTypeDef that has IfcBeam as TypedClass attribute, is a valid Relationship for the TypeDefinition of this class.
WR62	The material attribute of a beam shall use IfcMaterialComposite as the proper select type.

Interface Definitions

• I_Beam

Runtime Type Definitions

Geometry Use Definitions

Object Geometry in Context

The geometric representation of IfcBeam is given by the IfcProductShape, allowing multiple geometric representation. Included are:

Local Placement

The definition of the object coordinate system for IfcBeam is defined in it’s supertype IfcProduct. It is defined by the

• IfcLocalPlacement, which defines the local coordinate system that is referenced by all geometric representations.

Standard Geometric Representation

The standard geometric representation of IfcBeam is defined using the attribute driven geometry. The following constraints apply to the standard representation:

• Solid: IfcAttDrivenExtrudedSolid is required, referring to a single segment,
• Segment: IfcAttDrivenExtrudedSegment is required,
• Profile: IfcRectangleProfileDef shall be supported.
• Extrusion: The profile shall be extruded horizontally, i.e., coplanar to the XY plane of the co-ordinate system of element container, i.e. site, building or building storey)

Example for standard geometric representation

 

Extrusion  Extrusion path, for standard representation given by IfcAttDrivenExtrudedSolid referencing a single IfcAttDrivenExtrudedSegment  Default Type: IfcAttDrivenExtrudedSegment  IfcAttDrivenExtrudedSegment.Depth, Extrusion path defined by a positive length measure along the local z-axis, interpreted as beam length Profile  Extrusion profile, for standard representation given by IfcAttDrivenExtrudedSegment referencing IfcAttDrivenProfileDef   Default Type: IfcRectangleProfileDef  YDim interpreted as beam width, XDim interpreted as beam height. Extrusion Direction  The beam profile is extruded horizontally, i.e. coplanar to the XY plane of the co-ordinate system of the building storey.  Placement  [Black arrows] The local placement of beam is placed relative to the co-ordinate system of the element container object, here IfcBuildingStorey.  [Red arrows] The segment is placed relative to the local placement.  [Green arrows] The profile is placed relative to the XY plane of the placement co-ordinate system of the segment.

Advanced Geometric Representation

The advanced geometric representation of IfcBeam is defined using the attribute driven geometry. The following constraints apply to the advanced representation:

• Solid: IfcAttDrivenExtrudedSolid and IfcAttDrivenClippedExtrudedSolid is required, referring to a single or multiple segments,
• Segment: IfcAttDrivenExtrudedSegment, IfcAttDrivenTaperedExtrudedSegment, and IfcAttDrivenMorphedExtrudedSegment is required,
• Profile: IfcRectangleProfileDef, IfcCircleProfileDef and IfcArbitraryProfileDef shall be supported.
• Extrusion: All extrusion directions shall be supported

Example for advanced geometric representation

Extrusion  Extrusion path, for standard representation given by IfcAttDrivenExtrudedSolid or IfcAttDrivenClippedExtrudedSolid referencing multiple (here two) IfcAttDrivenExtrudedSegment.  Default Type: Set of IfcAttDrivenExtrudedSegment and/or of IfcAttDrivenMorphedExtrudedSegment and/or IfcAttDrivenTaperedExtrudedSegment (Hereby haunched beams are supported)  IfcAttDrivenExtrudedSegment[1..n].Depth, Extrusion paths defined by a positive length measure along the local z-axis.  In case of IfcAttDrivenMorphedExtrudedSegment start and end profiles are given (see type for constraints on morphing) Profile  Extrusion profile, for standard representation given by each IfcAttDrivenExtrudedSegment referencing IfcAttDrivenProfileDef  Default Type: IfcRectangleProfileDef  YDim interpreted as beam width, XDim interpreted as beam heigth. Other Types: IfcCircleProfileDef Radius interpreted as beam radius. Other Types: IfcArbitraryProfileDef  IfcBoundedCurve (closed and 2D) defining an arbitrary beam shape Extrusion Direction  The beam profile is extruded in any direction.  Placement  [Black arrows] The local placement of beam is placed relative to the co-ordinate system of the element container (e.g. the building storey).  [Red and brown arrows] The segments are placed relative to the local placement.  [Green and blue arrows] The profiles are placed relative to the XY planes of the placement co-ordinate systems of the segments.

Arbitrary Geometric Representation

The arbitrary geometric representation of IfcBeam is defined using explicit geometry. The faceted B-Rep capabilities (with or without voids) shall be supported for arbitrary representation.

Class IfcBuiltIn

EXPRESS Definition

Class Semantic Definition

Definition from IFC: Generalization for elements that are assembled on site; built-in and attached to the building permanently (e.g. built-in cabinets, countertops, railings, etc.).

NOTE This class was IfcBuiltIn in IFC Release 1.0 and has been modified in IFC Release 1.5.

ISSUE See issue I-159 for changes made in IFC Release 1.5.

Attribute and Relationship Definitions

Inherited Classes

Formal Propositions:

WR61	Only IfcPropertyTypeDef that has IfcBuiltIn as TypedClass attribute, is a valid Relationship for the TypeDefinition of this class.

Interface Definitions

• I_BuiltIn

Runtime Type Definitions

Geometry Use Definitions

Object Geometry in Context

The geometric representation of IfcBuiltIn is given by the IfcProductShape, allowing multiple geometric representation. Included are:

Local Position

The Reference Geometry for IfcBuiltIn is defined in it’s supertype IfcProduct. It is defined by the

• IfcLocalPlacement, which defines the local coordinate system that is referenced by all geometric representations.

Standard Geometric Representation

The standard geometric representation of IfcBuiltIn is defined using explicit geometry. The faceted B-Rep capabilities (with or without voids) shall be supported for standard representation.

Currently, the usage of attribute driven geometry for IfcBuiltIn is not supported.

Advanced Geometric Representation

The advanced geometric representation of IfcBuiltIn is defined using explicit geometry. The faceted B-Rep capabilities (with or without voids) shall be supported for standard representation.

Currently, the usage of attribute driven geometry for IfcBuiltIn is not supported.

Arbitrary Geometric Representation

The arbitrary geometric representation of IfcBuiltIn is defined using explicit geometry. The faceted B-Rep capabilities (with or without voids) shall be supported for standard representation.

Currently, there is no difference in the usage of standard, advanced and arbitrary geometric representations for IfcBuiltIn.

Class IfcColumn

EXPRESS Definition

Class Semantic Definition

Definition from IFC: A vertical structural member which often is aligned with a structural grid intersection. IfcColumn is defined in the Architecture Domain and possibly reused by other domains. It represents a vertical, or nearly vertical structural member designed to transfer loads to its base.

NOTE This class was IfcColumn in IFC Release 1.0 and has been modified in IFC Release 1.5 ISSUE See issues I-330, I-365 for changes made in IFC Release 1.5.1

Attribute and Relationship Definitions

Inherited Classes

Formal Propositions:

WR61	Only IfcPropertyTypeDef that has IfcColumn as TypedClass attribute, is a valid Relationship for the TypeDefinition of this class.
WR62	The material attribute of a beam shall use IfcMaterialComposite as the proper select type.

Interface Definitions

• I_Column

Runtime Type Definitions

Geometry Use Definitions

Object Geometry in Context

The geometric representation of IfcColumn is given by the IfcProductShape, allowing multiple geometric representation. Included are:

Local Placement

The Reference Geometry for IfcColumn is defined in it’s supertype IfcProduct. It is defined by the

• IfcLocalPlacement, which defines the local coordinate system that is referenced by all geometric representations.

Standard Geometric Representation

The standard geometric representation of IfcColumn is defined using the attribute driven geometry. The following constraints apply to the standard representation:

• Solid: IfcAttDrivenExtrudedSolid is required, referring to a single segment,
• Segment: IfcAttDrivenExtrudedSegment is required,
• Profile: IfcRectangleProfileDef and IfcCircleProfileDef shall be supported.
• Extrusion: The profile shall be extruded vertically, i.e., along the positive Z Axis of the co-ordinate system of element container, i.e. site, building or building storey)

Example for standard geometric representation

 

Extrusion  Extrusion path, for standard representation given by IfcAttDrivenExtrudedSolid referencing a single IfcAttDrivenExtrudedSegment  Default Type: IfcAttDrivenExtrudedSegment  IfcAttDrivenExtrudedSegment.Depth, Extrusion path defined by a positive length measure along the local z-axis, interpreted as column height Profile  Extrusion profile, for standard representation given by IfcAttDrivenExtrudedSegment referencing IfcAttDrivenProfileDef   Default Type: IfcRectangleProfileDef  YDim interpreted as column width, XDim interpreted as column height. Other Type: IfcCircleProfileDef (used in example)  Radius is interpreted as column radius. Extrusion Direction  The column profile is extruded vertically, i.e. along the z-axis of the co-ordinate system of the building storey.  Placement  [Black arrows] The local placement of beam is placed relative to the co-ordinate system of the element container object, here IfcBuildingStorey.  [Red arrows] The segment is placed relative to the local placement.  [Green arrows] The profile is placed relative to the XY plane of the placement co-ordinate system of the segment.

Advanced Geometric Representation

The advanced geometric representation of IfcColumn is defined using the attribute driven geometry. The following constraints apply to the advanced representation:

• Solid: IfcAttDrivenExtrudedSolid and IfcAttDrivenClippedExtrudedSolid is required, referring to a single or multiple segments,
• Segment: IfcAttDrivenExtrudedSegment, IfcAttDrivenTaperedExtrudedSegment and IfcAttDrivenMorphedExtrudedSegment is required,
• Profile: IfcRectangleProfileDef, IfcCircleProfileDef and IfcArbitraryProfileDef shall be supported.
• Extrusion: All extrusion directions shall be supported

Example for advanced geometric representation

 

Extrusion  Extrusion path, for standard representation given by IfcAttDrivenExtrudedSolid referencing multiple (here two) IfcAttDrivenExtrudedSegment.   Default Type: Set of IfcAttDrivenExtrudedSegment and/or of IfcAttDrivenMorphedExtrudedSegment and/or IfcAttDrivenTaperedExtrudedSegment (Hereby "mushroom" columns are supported)  IfcAttDrivenExtrudedSegment[1..n].Depth, Extrusion paths defined by a positive length measure along the local z-axis. In case of IfcAttDrivenMorphedExtrudedSegment start and end profiles are given (see type for constraints on morphing) Profile  Extrusion profile, for standard representation given by each IfcAttDrivenExtrudedSegment referencing IfcAttDrivenProfileDef   Default Type: IfcRectangleProfileDef  YDim interpreted as column width, XDim interpreted as column depth. Other Types: IfcCircleProfileDef (used in example)  Radius interpreted as column radius. Other Types: IfcArbitraryProfileDef  IfcBoundedCurve (closed and 2D) defining an arbitrary column shape Extrusion Direction  The column profile is extruded in any direction.  Placement  [Black arrows] The local placement of column is placed relative to the co-ordinate system of the element container, e.g. the building storey.  [Red and brown arrows] The segments are placed relative to the local placement.  [Green and blue arrows] The profiles are placed relative to the XY planes of the placement co-ordinate systems of the segments.

Arbitrary Geometric Representation

The arbitrary geometric representation of IfcColumn is defined using explicit geometry. The faceted B-Rep capabilities (with or without voids) shall be supported for arbitrary representation.

Class IfcCovering

EXPRESS Definition

Class Semantic Definition

Definition from IFC: Supertype for any object which covers some part of and is fully dependent on another. Additionally, the geometry for this object is determined by the ‘owning’ object. Examples include wall, floor and ceiling coverings, finish trim, and base molding.

NOTE This class was IfcCovering in IFC Release 1.0 and has been modified in IFC Release 1.5

ISSUE See issue I-195 for changes made in IFC Release 1.5.
See issues I-330, I-365 for changes made in IFC Release 1.5.1

Attribute and Relationship Definitions

Inherited Classes

Formal Propositions:

WR61	Only IfcPropertyTypeDef that has IfcCovering as TypedClass attribute, is a valid Relationship for the TypeDefinition of this class.
WR62	The material attribute of a covering shall use IfcMaterialLayerSet as the proper select type.

Interface Definitions

• I_Covering

Runtime Type Definitions

Geometry Use Definitions

Object Geometry in Context

The geometric representation of IfcCovering is given by the IfcProductShape, allowing multiple geometric representation. Included are:

Local Placement

The Reference Geometry for IfcCovering is defined in it’s supertype IfcProduct. It is defined by the

• IfcLocalPlacement, which defines the local coordinate system that is referenced by all geometric representations.

Standard Geometric Representation

The standard geometric representation of IfcCovering is defined using the attribute driven geometry. The following constraints apply to the standard representation:

• Solid: only IfcAttDrivenExtrudedSolid is required, referring to a single segment,
• Segment: only IfcAttDrivenExtrudedSegment is required,
• Profile: only IfcRectangleProfileDef shall be supported.
• Extrusion: the profile shall be extruded along the z-axis of the local co-ordinate system of the building element which is covered (using the IfcRelCoversBldgElements relationship).

Example for standard geometric representation

 

Extrusion  Extrusion path, for standard representation given by IfcAttDrivenExtrudedSolid referencing a single IfcAttDrivenExtrudedSegment  Default Type: IfcAttDrivenExtrudedSegment  IfcAttDrivenExtrudedSegment.Depth, Extrusion path defined by a positive length measure along the local z-axis, interpreted as the length of the covering along the building element. Profile  Extrusion profile, for standard representation given by IfcAttDrivenExtrudedSegment referencing IfcAttDrivenProfileDef   Default Type: IfcRectangleProfileDef  YDim interpreted as covering thickness, XDim interpreted as height. Extrusion Direction  The covering profile is extruded horizontally, i.e. along the z-axis of the co-ordinate system of the building element, which is covered.  Placement  [Black arrows] The local placement of beam is placed relative to the co-ordinate system of the building element which is covered.  [Red arrows] The segment is placed relative to the local placement.  [Green arrows] The profile is placed relative to the XY plane of the placement co-ordinate system of the segment.

Advanced Geometric Representation

The advanced geometric representation of IfcCovering is defined using the attribute driven geometry. The following constraints apply to the advanced representation:

• Solid: IfcAttDrivenExtrudedSolid, IfcAttDrivenClippedExtrudedSolid and IfcAttDrivenRevolvedSolid, IfcAttDrivenClippedRevolvedSolid is required, referring to a single segment,
• Segment: IfcAttDrivenExtrudedSegment and IfcAttDrivenRevolvedSolid is required,
• Profile: IfcRectangleProfileDef and IfcArbitraryProfileDef shall be supported,
• Extrusion: the profile shall be extruded along the z-axis of the local co-ordinate system of the building element which is covered (using the IfcRelCoversBldgElements relationship).

Example for advanced geometric representation

Extrusion  Extrusion path, for standard representation given by IfcAttDrivenExtrudedSolid, IfcAttDrivenClippedExtrudedSolid and IfcAttDrivenRevolvedSolid, IfcAttDrivenClippedRevolvedSolid  referencing a single IfcAttDrivenExtrudedSegment or IfcAttDrivenRevolvedSolid.  Default Type: IfcAttDrivenExtrudedSegment  IfcAttDrivenExtrudedSegment.Depth, Extrusion path defined by a positive length measure along the local z-axis, interpreted as the length of the covering along the building element. Other Type: IfcAttDrivenRevolvedSegment (used in example)  IfcAttDrivenRevolvedSegment.Axis, IfcAxis1Placement defining the axis for revolution (shall be the same as for the covered building element); IfcAttDrivenRevolvedSegment.Angle plane angle measure defining the arc length of the covering along the building element. Profile  Extrusion profile, for standard representation given by IfcAttDrivenExtrudedSegment referencing IfcAttDrivenProfileDef  Default Type: IfcRectangleProfileDef  YDim interpreted as covering thickness, XDim interpreted as covering height  Other Type: IfcArbitraryProfileDef  CurveForSurface: closed bounded curve interpreted as covering area of the covering  Extrusion Direction  The covering profile is extruded horizontally, i.e. along the z-axis of the co-ordinate system of the building element, which is covered.  Placement  [Black arrows] The local placement of beam is placed relative to the co-ordinate system of the building element which is covered.  [Red arrows] The segment is placed relative to the local placement.  [Green arrows] The profile is placed relative to the XY plane of the placement co-ordinate system of the segment.

Arbitrary Geometric Representation

The arbitrary geometric representation of IfcColumn is defined using explicit geometry. The faceted B-Rep capabilities (with or without voids) shall be supported for arbitrary representation.

Class IfcDoor

EXPRESS Definition

Class Semantic Definition

Definition from IFC: IfcDoor is defined in the Architecture Domain and possibly reused by other domains. It represents a construction for closing an opening, intended primarily for access.

NOTE This class was IfcDoor in IFC Release 1.0 and has been modified in IFC Release 1.5

ISSUE See issue I-303, I-330 for changes made in IFC Release 1.5.1.

Attribute and Relationship Definitions

Inherited Classes

Formal Propositions:

WR61	Only IfcPropertyTypeDef that has IfcDoor as TypedClass attribute, is a valid Relationship for the TypeDefinition of this class.

Interface Definitions

• I_Door

Runtime Type Definitions

Geometry Use Definitions

Object Geometry in Context

The geometric representation of IfcDoor is given by the IfcProductShape, allowing multiple geometric representation. Included are:

Shape Aspect Representation

The IfcDoor represents an element that is usually mounted from various components. Therefore the Product Shape of IfcDoor will comprise usually many components. The number of recognized components and the depth of their representation, however, depends on the project life cycle.

The following standard components, if defined in the particular project life cycle, shall be recognizable within the shape representation as they are defined in the Property Sets. The IfcShapeAspect class and its Descriptor attribute shall be used to indicate the aspects of the geometric representation of IfcDoor that applies to the components.

 

Component	Descriptor (at IfcShapeAspect)
Lining	DoorLining
Panel	DoorPanel
Opening	DoorOpening
Opening Filler	DoorOpeningFiller
Trim	DoorTrim
Hardware	DoorHardware

Local Placement

The Reference Geometry for IfcDoor is defined in it’s supertype IfcProduct. It is defined by the

• IfcLocalPlacement, which defines the local coordinate system that is referenced by all geometric representations.

Standard Geometric Representation

The standard geometric representation of IfcDoor is defined using the explicit geometry. The following constraints apply to the standard representation:

• Solid: multiple instances (for each component) of IfcExtrudedAreaSolid are required, referring to a single segment,
• Profile: IfcCurveBoundedPlane shall be supported.
• Extrusion: The profiles shall be extruded horizontally, e.g., along the positive Z Axis of the co-ordinate system of IfcOpeningElement, in which the door is placed
• Boolean: To allow for componentized doors the IfcCsgSolid with the IfcBooleanResult capability shall be supported

Example for standard geometric representation

NOTE: The DoorPanel is only shown opened for better readability of the drawing. The parameters are only given for a DoorTrim as example.

Extrusion  Extrusion path, for standard representation given by IfcExtrudedAreaSolid for each component (DoorLining, DoorPanel, DoorOpening, DoorOpeningFiller, DoorTrim) for which a geometric representation is available.  IfcExtrudedAreaSolid.Depth, Extrusion path defined by a positive length measure along the local z-axis, interpreted as the thickness of the relevant component of the door. IfcExtrudedAreaSolid.ExtrudedDirection, Shall be identical with the z-axis of the placement co-ordinate system (normal of IfcPlane) for the profile Profile  Extrusion profile, for standard representation given by IfcCurveBoundedPlane  Interpreted as the profile (elevation view) of the relevant component of the door. Extrusion Direction  The profiles are extruded horizontally, i.e. in the same direction as the opening element, which is filled.  Placement  [Black arrows] The local placement of door is placed relative to the co-ordinate system of the opening element which is filled.  [Red arrows] The placement co-ordinate system of the basis surface, given by the normal of the IfcPlane.  [NOTE] All other component shapes are placed accordingly relative to the local placement.

Boolean Operation  All shapes (IfcAttDrivenExtrudedSolid) shall be connected by the CSG capabilities, resulting in an IfcCsgSolid as the standard representation item for the door. The Boolean structure for the example shall be:    (DoorLining)+((DoorTrim[1]+DoorTrim[2])+(DoorPanel-PanelOpening))

Advanced Geometric Representation

She advanced geometric representation is defined in the same way as the standard geometric representation for IfcDoor using the explicit geometry. In addition the advanced geometric representation shall support the shape aspect representation, i.e. each component shape (IfcAttDrivenExtrudedSolid) shall be defined as a shape aspect by using the IfcShapeAspect pointing to the IfcAttDrivenExtrudedSolid within the appropriate shape representation.

Arbitrary Geometric Representation

The arbitrary geometric representation of IfcDoor is defined using explicit geometry. The faceted B-Rep capabilities (with or without voids) shall be supported for arbitrary representation. An IfcFacetedBrep or IfcFacetedBrepWithVoids shall represent each component that has geometric representation.

Class IfcFloor

EXPRESS Definition

Class Semantic Definition

Definition from IFC: Construction that provides the lowest surface in any Space in a building. It shall be noted, that only the core or constructional part of this construction is considered to be a Floor. The upper finish (flooring) and the lower finish (ceiling) are considered to be Coverings.

NOTE This class was IfcFloor in IFC Release 1.0 and has been modified in IFC Release 1.5

ISSUE See issues I-155, I-156, I-157 for changes made in IFC Release 1.5.
See issues I-330, I-365 for changes made in IFC Release 1.5.1

Attribute and Relationship Definitions

Inherited Classes

Formal Propositions:

WR61	Only IfcPropertyTypeDef that has IfcFloor as TypedClass attribute, is a valid Relationship for the TypeDefinition of this class.
WR62	The material attribute of a floor shall use IfcMaterialLayerSet as the proper select type.

Interface Definitions

• I_Floor

Runtime Type Definitions

Geometry Use Definitions

Object Geometry in Context

The geometric representation of IfcFloor is given by the IfcProductShape, allowing multiple geometric representation. Included are:

Local Placement

The Reference Geometry for IfcFloor is defined in it’s supertype IfcProduct. It is defined by the

• IfcLocalPlacement, which defines the local coordinate system that is referenced by all geometric representations.

Standard Geometric Representation

The standard geometric representation of IfcFloor is defined using the attribute driven geometry. The following constraints apply to the standard representation:

• Solid: IfcAttDrivenExtrudedSolid is required, referring to a single segment,
• Segment: IfcAttDrivenExtrudedSegment is required,
• Profile: IfcRectangleProfileDef and IfcArbitraryProfileDef shall be supported.
• Extrusion: The profile shall be extruded vertically, i.e., along the positive Z Axis of the co-ordinate system of the element container, i.e. site, building or building storey.

Example for standard geometric representation:

 

Extrusion  Extrusion path, for standard representation given by IfcAttDrivenExtrudedSolid referencing a single IfcAttDrivenExtrudedSegment  Default Type: IfcAttDrivenExtrudedSegment  IfcAttDrivenExtrudedSegment.Depth, Extrusion path defined by a positive length measure along the local z-axis, interpreted as the thickness of the floor. Profile  Extrusion profile, for standard representation given by IfcAttDrivenExtrudedSegment referencing IfcAttDrivenProfileDef   Default Type: IfcRectangleProfileDef  XDim interpreted as length of floor slab, YDim interpreted as width of floor slab. Other Type: IfcArbitraryProfileDef  CurveForSurface: closed bounded curve interpreted as area (or foot print) of the floor slab. Extrusion Direction  The floor profile is extruded vertically, i.e. along the z-axis of the co-ordinate system of the element container (e.g., the building storey).  Placement  [Black arrows] The local placement of floor is placed relative to the co-ordinate system of the element container, e.g., the building storey.  [Red arrows] The segment is placed relative to the local placement.  [Green arrows] The profile is placed relative to the XY plane of the placement co-ordinate system of the segment.

Advanced Geometric Representation

The advanced geometric representation of IfcFloor is defined using the attribute driven geometry. The following constraints apply to the advanced representation:

• Solid: IfcAttDrivenExtrudedSolid and IfcAttDrivenClippedExtrudedSolid is required, referring to a single segment,
• Segment: IfcAttDrivenExtrudedSegment is required,
• Profile: IfcRectangleProfileDef and IfcArbitraryProfileDef shall be supported.
• Extrusion: The profile shall be extruded into any direction.

Example for advanced geometric representation:

 

Extrusion  Extrusion path, for standard representation given by IfcAttDrivenExtrudedSolid or IfcAttDrivenClippedExtrudedSolid referencing a single IfcAttDrivenExtrudedSegment  Default Type: IfcAttDrivenExtrudedSegment  IfcAttDrivenExtrudedSegment.Depth, Extrusion path defined by a positive length measure along the local z-axis, interpreted as the thickness of the floor. Profile  Extrusion profile, for standard representation given by IfcAttDrivenExtrudedSegment referencing IfcAttDrivenProfileDef   Default Type: IfcRectangleProfileDef  XDim interpreted as length of floor slab, YDim interpreted as width of floor plate. Other Type: IfcArbitraryProfileDef  CurveForSurface: closed bounded curve interpreted as area (or foot print) of the floor plate. Extrusion Direction  The floor profile shall be extruded into any direction.  Placement  [Black arrows] The local placement of floor is placed relative to the co-ordinate system of the element container, e.g., the building storey.  [Red arrows] The segment is placed relative to the local placement.  [Green arrows] The profile is placed relative to the XY plane of the placement co-ordinate system of the segment.

Arbitrary Geometric Representation

The arbitrary geometric representation of IfcFloor is defined using explicit geometry. The faceted B-Rep capabilities (with or without voids) shall be supported for arbitrary representation.

Class IfcRelCoversBldgElements

EXPRESS Definition

Class Semantic Definition

Definition from IFC: Objectified relationship between an IfcBuildingElement and one to many IfcCovering, which do cover the building element.

NOTE This is a new class in IFC Release 1.5

Attribute and Relationship Definitions

Inherited Classes

Interface Definitions

• I_RelCoversBldgElements

Runtime Type Definitions

Objectified relationships are not typed – there is no type definition.

Geometry Use Definitions

This objectified relationship does not carry additional geometry – there is no geometry use definition.

Class IfcRoofSlab

EXPRESS Definition

Class Semantic Definition

Definition from IFC: Slab (shape) component of the construction that encloses a building from above. Note that more roof assembly elements will be included in future releases. A complex roof is constructed from possibly more than one Roof Slab.

NOTE This class was IfcRoofSlab in IFC Release 1.0 and has been modified in IFC Release 1.5

ISSUE See issues I-155, I-156, I-157 for changes made in IFC Release 1.5.
See issues I-330, I-365 for changes made in IFC Release 1.5.1

Attribute and Relationship Definitions

Inherited Classes

Formal Propositions:

WR61	Only IfcPropertyTypeDef that has IfcRoofSlab as TypedClass attribute, is a valid Relationship for the TypeDefinition of this class.
WR62	The material attribute of a roof slab shall use IfcMaterialLayerSet as the proper select type.

Interface Definitions

• I_RoofSlab

Runtime Type Definitions

Geometry Use Definitions

Object Geometry in Context

The geometric representation of IfcRoofSlab is given by the IfcProductShape, allowing multiple geometric representation. The same geometry use definitions as for IfcFloor apply. Included are:

Local Placement

The Reference Geometry for IfcRoofSlab is defined in it’s supertype IfcProduct. It is defined by the

• IfcLocalPlacement, which defines the local coordinate system that is referenced by all geometric representations.

Standard Geometric Representation

The standard geometric representation of IfcRoofSlab is defined using the attribute driven geometry. The following constraints apply to the standard representation:

• Solid: IfcAttDrivenExtrudedSolid is required, referring to a single segment.
• Segment: IfcAttDrivenExtrudedSegment is required.
• Profile: IfcRectangleProfileDef and IfcArbitraryProfileDef shall be supported.
• Extrusion: The profile shall be extruded vertically, i.e., along the positive Z Axis of the co-ordinate system of the element container, i.e. site, building or building storey

Example for standard geometric representation

 

Extrusion  Extrusion path, for standard representation given by IfcAttDrivenExtrudedSolid referencing a single IfcAttDrivenExtrudedSegment  Default Type: IfcAttDrivenExtrudedSegment  IfcAttDrivenExtrudedSegment.Depth, Extrusion path defined by a positive length measure along the local z-axis, interpreted as the thickness of the roof slab. Profile  Extrusion profile, for standard representation given by IfcAttDrivenExtrudedSegment referencing IfcAttDrivenProfileDef   Default Type: IfcRectangleProfileDef  XDim interpreted as length of roof slab, YDim interpreted as width of roof slab. Other Type: IfcArbitraryProfileDef  CurveForSurface: closed bounded curve interpreted as area (or foot print) of the roof slab. Extrusion Direction  The roof slab profile is extruded vertically, i.e. along the z-axis of the co-ordinate system of the element container (e.g., the building storey).  Placement  [Black arrows] The local placement of roof slab is placed relative to the co-ordinate system of the element container, e.g., the building storey.  [Red arrows] The segment is placed relative to the local placement.  [Green arrows] The profile is placed relative to the XY plane of the placement co-ordinate system of the segment.

Advanced Geometric Representation

The advanced geometric representation of IfcRoofSlab is defined using the attribute driven geometry. The following constraints apply to the advanced representation:

• Solid: IfcAttDrivenExtrudedSolid and IfcAttDrivenClippedExtrudedSolid is required, referring to a single or multiple segments.
• Segment: IfcAttDrivenExtrudedSegment is required.
• Profile: IfcRectangleProfileDef and IfcArbitraryProfileDef shall be supported.
• Extrusion: All extrusion directions shall be supported.

Example for advanced geometric representation

 

Extrusion  Extrusion path, for standard representation given by IfcAttDrivenExtrudedSolid or IfcAttDrivenClippedExtrudedSolid referencing a single IfcAttDrivenExtrudedSegment  Default Type: IfcAttDrivenExtrudedSegment  IfcAttDrivenExtrudedSegment.Depth, Extrusion path defined by a positive length measure along the local z-axis, interpreted as the thickness of the roof slab. Profile  Extrusion profile, for standard representation given by IfcAttDrivenExtrudedSegment referencing IfcAttDrivenProfileDef   Default Type: IfcRectangleProfileDef  XDim interpreted as length of roof slab, YDim interpreted as width of roof slab. Other Type: IfcArbitraryProfileDef  CurveForSurface: closed bounded curve interpreted as area (or foot print) of roof slab. Extrusion Direction  The roof slab profile shall be extruded into any direction.  Placement  [Black arrows] The local placement of roof slab is placed relative to the co-ordinate system of the element container, e.g., the building storey.  [Red arrows] The segment is placed relative to the local placement.  [Green arrows] The profile is placed relative to the XY plane of the placement co-ordinate system of the segment.

Arbitrary Geometric Representation

The arbitrary geometric representation of IfcRoofSlab is defined using explicit geometry. The faceted B-Rep capabilities (with or without voids) shall be supported for arbitrary representation.

Class IfcWall

EXPRESS Definition

Class Semantic Definition

Definition from IFC: IfcWall represents a vertical construction that bounds or subdivides Spaces. It is the common concept of a wall that will be later specialized in the various domains.

NOTE This class was IfcWall in IFC Release 1.0 and has been modified in IFC Release 1.5

ISSUE See issue I-155, I-156, I-157 for changes made in IFC Release 1.5.
See issues I-288, I-330, I-365 for changes made in IFC Release 1.5.1

Attribute and Relationship Definitions

Inherited Classes

Formal Propositions:

WR61	Only IfcPropertyTypeDef that has IfcWall as TypedClass attribute, is a valid Relationship for the TypeDefinition of this class.
WR62	The material attribute of a wall shall use IfcMaterialLayerSet as the proper select type.

Interface Definitions

• I_Wall

Runtime Type Definitions

Geometry Use Definitions

Object Geometry in Context

The geometric representation of IfcWall is given by the IfcProductShape, allowing multiple geometric representation. Included are:

Local Placement

The Reference Geometry for IfcWall is defined in it’s supertype IfcProduct. It is defined by the

• IfcLocalPlacement, which defines the local coordinate system that is referenced by all geometric representations.

Standard Geometric Representation

The standard geometric representation of IfcWall is defined using the attribute driven geometry. The following constraints apply to the standard representation:

• Solid: IfcAttDrivenExtrudedSolid is required, referring to a single segment.
• Segment: IfcAttDrivenExtrudedSegment is required.
• Profile: IfcRectangleProfileDef shall be supported.
• Extrusion: The profile shall be extruded horizontally, i.e., coplanar to the XY Plane of the co-ordinate system of the element container
• Connection: The IfcRelConnectsPathElements relationship shall be used at least for both horizontal ends of the IfcWall, if those ends connect to other building elements. The connection geometry shall not be specified to allow for logical connections using the priorities only. Only single layer walls can be connected.

Example for standard geometric representation

Extrusion  Extrusion path, for standard representation given by IfcAttDrivenExtrudedSolid referencing a single IfcAttDrivenExtrudedSegment  Default Type: IfcAttDrivenExtrudedSegment  IfcAttDrivenExtrudedSegment.Depth, Extrusion path defined by a positive length measure along the local z-axis, interpreted as the length of the wall. Profile  Extrusion profile, for standard representation given by IfcAttDrivenExtrudedSegment referencing IfcAttDrivenProfileDef   Default Type: IfcRectangleProfileDef  YDim interpreted as wall thickness, XDim interpreted as wall height. Extrusion Direction  The wall profile is extruded horizontally, i.e. co-planar to the XY plane of the co-ordinate system of the element container, e.g. the building storey.  Placement  [Black arrows] The local placement of beam is placed relative to the co-ordinate system of the building element which is covered.  [Red arrows] The segment is placed relative to the local placement.  [Green arrows] The profile is placed relative to the XY plane of the placement co-ordinate system of the segment.

Connection  The walls are connected using the IfcRelConnectsPathElements logical relationship, i.e. no connection geometry is given. The intersection of both lengthened walls (when viewed in ground view) shall be added to the wall with higher priorities (as given by the RelatingPriorities and RelatedPriorities attributes. If the priorities are equal, the intersection shall be added to the RelatingElement.  The following additional propositions for standard geometric representation (with standard connectivity) apply:  Both walls shall be single layer walls Both walls shall have the same height (XDim attribute)

Advanced Geometric Representation

The advanced geometric representation of IfcWall is defined using the attribute driven geometry. The following constraints apply to the advanced representation:

• Solid: IfcAttDrivenExtrudedSolid, IfcAttDrivenClippedExtrudedSolid and IfcAttDrivenRevolvedSolid, IfcAttDrivenClippedRevolvedSolid is required, referring to a single or multiple segments.
• Segment: IfcAttDrivenExtrudedSegment, IfcAttDrivenRevolvedSegment is required.
• Profile: IfcRectangleProfileDef shall be supported.
• Extrusion: The profile shall be extruded horizontally, i.e., coplanar to the XY Plane of the co-ordinate system of the element container i.e. site, building or building storey.
• Connection: The IfcRelConnectsPathElements relationship shall be used at least for both horizontal ends of the IfcWall, if those ends connect to other building elements. The connection geometry shall be specified as IfcLineConnectionGeometry to allow for an explicit definition of the shape for the wall ends. Single and multiple layer walls shall be connected.

Example for advanced geometric representation

Extrusion  Extrusion path, for standard representation given by IfcAttDrivenExtrudedSolid IfcAttDrivenClippedExtrudedSolid and IfcAttDrivenRevolvedSolid, IfcAttDrivenClippedRevolvedSolid referencing a single or multiple IfcAttDrivenExtrudedSegment and/or IfcAttDrivenRevolvedSegment   Default Type: IfcAttDrivenExtrudedSegment  IfcAttDrivenExtrudedSegment.Depth, Extrusion path defined by a positive length measure along the local z-axis, interpreted as the length of the wall. Other Type: IfcAttDrivenRevolvedSegment (used in example)  IfcAttDrivenRevolvedSegment.Axis, IfcAxis1Placement defining the axis for revolution; IfcAttDrivenRevolvedSegment.Angle plane angle measure defining the arc length of the wall. Profile  Extrusion profile, for standard representation given by IfcAttDrivenExtrudedSegment referencing IfcAttDrivenProfileDef   Default Type: IfcRectangleProfileDef  YDim interpreted as wall thickness, XDim interpreted as wall height. Extrusion Direction  The wall profile is extruded horizontally, i.e. co-planar to the XY plane of the co-ordinate system of the element container, e.g. the building storey.  Placement  [Black arrows] The local placement of wall is placed relative to the co-ordinate system of the element container (e.g. the building storey).  [Red and brown arrows] The segments are placed relative to the local placement.  [Green and blue arrows] The profiles are placed relative to the XY planes of the placement co-ordinate systems of the segments.