Defined in File Ifc4x1.h
IfcCurtainWall: public Ifc4x1::IfcBuildingElement¶
Definition from ISO 6707-1:1989: Non load bearing wall positioned on the outside of a building and enclosing it. A curtain wall is an exterior wall of a building which is an assembly of components, hung from the edge of the floor/roof structure rather than bearing on a floor. Curtain wall is represented as a building element assembly and implemented as a subtype of IfcBuildingElement that uses an IfcRelAggregates relationship. HISTORY New Entity in IFC Release 2.0
Type Use Definition IfcCurtainWall defines the occuurence of any curtain wall, common information about curtain wall types (or styles) is handled by IfcCurtainWallType. The IfcCurtainWallType (if present) may establish the commontype name, usage (or predefined) type, common material information, common set of properties and common shape representations (using IfcRepresentationMap). The IfcCurtainWallType is attached using the IfcRelDefinedByType.RelatingType objectified relationship and is accessible by the inverse IsDefinedBy attribute. If no IfcCurtainWallType is attached(i.e. if only occurrence information is given) the predefined type may be given by using the ObjectType attribute. NOTE Since the IfcCurtainWall might be represented as an aggregate of parts, e.g. represented by IfcMember, or IfcPlate, these individual parts may have type information attached (represented e.g. by IfcMemberType, or IfcPlateType). Property Set Use Definition: The property sets relating to the IfcCurtainWall are defined by the IfcPropertySet and attached by the IfcRelDefinesByProperties relationship. It is accessible by the inverse IsDefinedBy relationship. The following property set definitions specific to the IfcCurtainWall are part of this IFC release:
Pset_CurtainWallCommon: common property set for all curtain wall occurrences
Quantity Use Definition The quantities relating to the IfcCurtainWall are defined by the 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. Quantities shall never be assigned to the IfcCurtainWallType.
Qto_CurtainWallBaseQuantities: base quantities for all curtain wall occurrences.
Geometry Use Definitions: The geometric representation of IfcCurtainWall is given by the IfcProductDefinitionShape, allowing multiple geometric representations. Independent geometric representations, as described below, should only be used when the IfcCurtainWall is not defined as an aggregate. If defined as an aggregate, the geometric representation is the sum of the representations of the components within the aggregate. Local placement The local placement for IfcCurtainWall is defined in its supertype IfcProduct. It is defined by the IfcLocalPlacement, which defines the local coordinate system that is referenced by all geometric representations.
The PlacementRelTo relationship of IfcLocalPlacement shall point (if given) to the same IfcSpatialStructureElement that is used in the ContainedInStructure inverse attribute or to a referenced spatial structure element at a higher level. If the relative placement is not used, the absolute placement is defined within the world coordinate system.
If the IfcCurtainWall establishes an aggregate, then all contained elements (defined by the IsDecomposedBy inverse attribute) shall be placed relative to the IfcCurtainWall.ObjectPlacement. Geometric Representation The geometric representation of IfcCurtainWall is defined using the following multiple shape representations for its definition:
Axis: A two-dimensional open curve (for restrictions see below) defining the axis for the curtain wall.
This is an optional representation for curtain walls.
Body: A surface model or boundary representation model representation defining the 3D shape of the curtain wall.
If the IfcCurtainWall has components (referenced by SELF\IfcObject.IsDecomposedBy) then no independent shape representation with RepresentationType = ‘Body’ shall be defined. The body of IfcCurtainWall is then geometrically represented by the shape representation of its components. The components are accessed via SELF\IfcObject.IsDecomposedBy.RelatedObjects.
If the IfcCurtainWall has no components defined (empty set of SELF\IfcObject.IsDecomposedBy) then the IfcCurtainWall may be represented by an shape representation with the RepresentationIdentifier = ‘Body’.
Axis Representation The axis geometric representation of IfcCurtainWall is defined using the ‘Axis’ representation. The following attribute values for the IfcShapeRepresentation holding this geometric representation shall be used:
RepresentationIdentifier : ‘Axis’ RepresentationType : ‘Curve2D’
The following additional constraints apply to the ‘Axis’ representation:
Body Representation The body shape representation of IfcCurtainWall is defined using the ‘Body’ representation. The following attribute values for the IfcShapeRepresentation holding this geometric representation shall be used:
RepresentationIdentifier : ‘Body’ RepresentationType : ‘SurfaceModel’, ‘Brep’ and ‘MappedRepresentation’
An own ‘Body’ representation shall only be included if no components of the curtain wall are defined.
Whether the optional attribute PredefinedType is defined for this IfcCurtainWall.
Predefined generic type for a curtain wall that is specified in an enumeration. There may be a property set given specificly for the predefined types. NOTE The PredefinedType shall only be used, if no type object IfcCurtainWallType is assigned, providing its own IfcCurtainWallType.PredefinedType.
IFC2x4 CHANGE The attribute has been added at the end of the entity definition.
IfcCurtainWall(std::string v1_GlobalId, ::Ifc4x1::IfcOwnerHistory *v2_OwnerHistory, boost::optional<std::string> v3_Name, boost::optional<std::string> v4_Description, boost::optional<std::string> v5_ObjectType, ::Ifc4x1::IfcObjectPlacement *v6_ObjectPlacement, ::Ifc4x1::IfcProductRepresentation *v7_Representation, boost::optional<std::string> v8_Tag, boost::optional<::Ifc4x1::IfcCurtainWallTypeEnum::Value> v9_PredefinedType)¶