Mur rideau

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.

NOTE  Definition according to ISO 6707-1: non load bearing wall positioned on the outside of a building and enclosing it.
HISTORY  New entity in IFC2.0

The geometric representation of IfcCurtainWall is given by the IfcProductDefinitionShape, allowing multiple geometric representations. Independent 'Body' geometric representation, 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.

The geometric representation of IfcCurtainWall is defined using the following multiple shape representations for its definition:

Common Use Definitions

The following concepts are inherited at supertypes:

 Instance diagram

Object Typing

The Object Typing concept applies to this entity as shown in Table 114.

Table 114 — IfcCurtainWall Object Typing

Property Sets for Objects

The Property Sets for Objects concept applies to this entity as shown in Table 115.

Table 115 — IfcCurtainWall Property Sets for Objects

Quantity Sets

The Quantity Sets concept applies to this entity as shown in Table 116.

Table 116 — IfcCurtainWall Quantity Sets

Spatial Containment

The Spatial Containment concept applies to this entity as shown in Table 117.
IfcBuildingStoreyDefault spatial container
IfcBuildingSpatial container for the element if it cannot be assigned to a building storey - curtain wall facades may be assigned directly to the building
IfcSiteSpatial container for the element in case that it is placed on site (outside of building)

Table 117 — IfcCurtainWall Spatial Containment

Product Placement

The Product Placement concept applies to this entity as shown in Table 118.
IfcLocalPlacementIfcLocalPlacementRelative placement according to position and rotation relative to container.
IfcLocalPlacement Absolute placement according to position and rotation of world coordinate system.
IfcGridPlacement Placement according to grid intersection.

Table 118 — IfcCurtainWall Product Placement

The following restriction may be imposed by view definitions or implementer agreements:

Axis 2D Geometry

The Axis 2D Geometry concept applies to this entity.

The following additional constraints apply to the 'Axis' representation:

XSD Specification:

 <xs:element name="IfcCurtainWall" type="ifc:IfcCurtainWall" substitutionGroup="ifc:IfcBuildingElement" nillable="true"/>
 <xs:complexType name="IfcCurtainWall">
   <xs:extension base="ifc:IfcBuildingElement">
    <xs:attribute name="PredefinedType" type="ifc:IfcCurtainWallTypeEnum" use="optional"/>

EXPRESS Specification:

ENTITY IfcCurtainWall
SUBTYPE OF IfcBuildingElement;
PredefinedType : OPTIONAL IfcCurtainWallTypeEnum;
CorrectPredefinedType : NOT(EXISTS(PredefinedType)) OR (PredefinedType <> IfcCurtainWallTypeEnum.USERDEFINED) OR ((PredefinedType = IfcCurtainWallTypeEnum.USERDEFINED) AND EXISTS (SELF\IfcObject.ObjectType));
CorrectTypeAssigned : (SIZEOF(IsTypedBy) = 0) OR ('IFCSHAREDBLDGELEMENTS.IFCCURTAINWALLTYPE' IN TYPEOF(SELF\IfcObject.IsTypedBy[1].RelatingType));

Link to EXPRESS-G diagram EXPRESS-G diagram

Attribute Definitions:

PredefinedType : 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 IfcCurtainWallType is assigned, providing its own IfcCurtainWallType.PredefinedType.
IFC4 CHANGE The attribute has been added at the end of the entity definition.

Formal Propositions:

CorrectPredefinedType : Either the PredefinedType attribute is unset (e.g. because an IfcCurtainWallType is associated), or the inherited attribute ObjectType shall be provided, if the PredefinedType is set to USERDEFINED.
CorrectTypeAssigned : Either there is no curtain wall type object associated, i.e. the IsTypedBy inverse relationship is not provided, or the associated type object has to be of type IfcCurtainWallType.

Inheritance Graph:

ENTITY IfcCurtainWall
GlobalId : IfcGloballyUniqueId;
OwnerHistory : OPTIONAL IfcOwnerHistory;
Name : OPTIONAL IfcLabel;
Description : OPTIONAL IfcText;
ENTITY IfcObjectDefinition
HasAssignments : SET OF IfcRelAssigns FOR RelatedObjects;
Nests : SET [0:1] OF IfcRelNests FOR RelatedObjects;
IsNestedBy : SET OF IfcRelNests FOR RelatingObject;
HasContext : SET [0:1] OF IfcRelDeclares FOR RelatedDefinitions;
IsDecomposedBy : SET OF IfcRelAggregates FOR RelatingObject;
Decomposes : SET [0:1] OF IfcRelAggregates FOR RelatedObjects;
HasAssociations : SET OF IfcRelAssociates FOR RelatedObjects;
ENTITY IfcObject
ObjectType : OPTIONAL IfcLabel;
IsDeclaredBy : SET [0:1] OF IfcRelDefinesByObject FOR RelatedObjects;
Declares : SET OF IfcRelDefinesByObject FOR RelatingObject;
IsTypedBy : SET [0:1] OF IfcRelDefinesByType FOR RelatedObjects;
IsDefinedBy : SET OF IfcRelDefinesByProperties FOR RelatedObjects;
ENTITY IfcProduct
ObjectPlacement : OPTIONAL IfcObjectPlacement;
Representation : OPTIONAL IfcProductRepresentation;
ReferencedBy : SET OF IfcRelAssignsToProduct FOR RelatingProduct;
ENTITY IfcElement
Tag : OPTIONAL IfcIdentifier;
FillsVoids : SET [0:1] OF IfcRelFillsElement FOR RelatedBuildingElement;
ConnectedTo : SET OF IfcRelConnectsElements FOR RelatingElement;
IsInterferedByElements : SET OF IfcRelInterferesElements FOR RelatedElement;
InterferesElements : SET OF IfcRelInterferesElements FOR RelatingElement;
HasProjections : SET OF IfcRelProjectsElement FOR RelatingElement;
ReferencedInStructures : SET OF IfcRelReferencedInSpatialStructure FOR RelatedElements;
HasOpenings : SET OF IfcRelVoidsElement FOR RelatingBuildingElement;
IsConnectionRealization : SET OF IfcRelConnectsWithRealizingElements FOR RealizingElements;
ProvidesBoundaries : SET OF IfcRelSpaceBoundary FOR RelatedBuildingElement;
ConnectedFrom : SET OF IfcRelConnectsElements FOR RelatedElement;
ContainedInStructure : SET [0:1] OF IfcRelContainedInSpatialStructure FOR RelatedElements;
ENTITY IfcBuildingElement
HasCoverings : SET OF IfcRelCoversBldgElements FOR RelatingBuildingElement;
ENTITY IfcCurtainWall
PredefinedType : OPTIONAL IfcCurtainWallTypeEnum;

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