The wall represents a vertical construction that bounds or subdivides spaces. Wall are usually vertical, or nearly vertical, planar elements, often designed to bear structural loads. A wall is however not required to be load bearing.

NOTE  Definition according to ISO 6707-1: vertical construction usually in masonry or in concrete which bounds or subdivides a construction works and fulfils a load bearing or retaining function.
NOTE  There is a representation of walls for structural analysis provided by a proper subtype of IfcStructuralMember being part of the IfcStructuralAnalysisModel.
NOTE  An arbitrary planar element to which this semantic information is not applicable (is not predominantly vertical), shall be modeled as IfcPlate.

A wall may have openings, such as wall openings, openings used for windows or doors, or niches and recesses. They are defined by an IfcOpeningElement attached to the wall using the inverse relationship HasOpenings pointing to IfcRelVoidsElement.

There are three entities for wall occurrences:

HISTORY  New entity in IFC1.0

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 183.

Table 183 — IfcWall Object Typing

Property Sets for Objects

The Property Sets for Objects concept applies to this entity as shown in Table 184.

Table 184 — IfcWall Property Sets for Objects

Quantity Sets

The Quantity Sets concept applies to this entity as shown in Table 185.

Table 185 — IfcWall Quantity Sets

Material Layer Set

The Material Layer Set concept applies to this entity.

The material of the IfcWall is defined by IfcMaterialLayerSet, or as fallback by IfcMaterial, and it is attached either directly or at the IfcWallType.

NOTE  It is illegal to assign an IfcMaterialLayerSetUsage to an IfcWall. Only the subtype IfcWallStandardCase supports this concept.

Path Connectivity

The Path Connectivity concept applies to this entity as shown in Table 186.
IfcWallWalls with equal or lower priority are connected at RelatedElement.

Table 186 — IfcWall Path Connectivity

Spatial Containment

The Spatial Containment concept applies to this entity as shown in Table 187.
IfcBuildingStoreyDefault spatial container
IfcBuildingSpatial container for the element if it cannot be assigned to a building storey
IfcSiteSpatial container for the element in case that it is placed on site (outside of building)

Table 187 — IfcWall Spatial Containment

The IfcWall, as any subtype of IfcBuildingElement, may participate alternatively in one of the two different containment relationships:

Axis 2D Geometry

The Axis 2D Geometry concept applies to this entity as shown in Table 188.
AxisCurve2DIfcBoundedCurveThe wall axis of the wall.

Table 188 — IfcWall Axis 2D Geometry

NOTE  The 'Axis' is not used to locate the material layer set, only the subtype IfcWallStandardCase provides this capability.

Surface Geometry

The Surface Geometry concept applies to this entity.

NOTE  The 'Surface' can be used to define a surfacic model of the building (e.g. for analytical purposes, or for reduced Level of Detail representation).

Body SweptSolid Geometry

The Body SweptSolid Geometry concept applies to this entity.

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

NOTE  If the wall body can be described by a vertical extrusion of a polygonal footprint with constant thickness along the axis (where vertical = into the direction of the global Z axis), the subtype IfcWallStandardCase should be used. If the extrusion is not equal to global Z, then the IfcWall should be used.

Body Clipping Geometry

The Body Clipping Geometry concept applies to this entity.

Element Voiding

The Element Voiding concept applies to this entity as shown in Table 189.

Product Assignment

The Product Assignment concept applies to this entity as shown in Table 190.
IfcStructuralSurfaceMemberAn idealized structural member corresponding to the wall.
IfcTaskA task for operating on the wall.

Table 190 — IfcWall Product Assignment

XSD Specification:

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

EXPRESS Specification:

SUPERTYPE OF(ONEOF(IfcWallElementedCase, IfcWallStandardCase))
SUBTYPE OF IfcBuildingElement;
PredefinedType : OPTIONAL IfcWallTypeEnum;
CorrectPredefinedType : NOT(EXISTS(PredefinedType)) OR (PredefinedType <> IfcWallTypeEnum.USERDEFINED) OR ((PredefinedType = IfcWallTypeEnum.USERDEFINED) AND EXISTS (SELF\IfcObject.ObjectType));
CorrectTypeAssigned : (SIZEOF(IsTypedBy) = 0) OR ('IFCSHAREDBLDGELEMENTS.IFCWALLTYPE' IN TYPEOF(SELF\IfcObject.IsTypedBy[1].RelatingType));

Link to EXPRESS-G diagram EXPRESS-G diagram

Attribute Definitions:

PredefinedType : Predefined generic type for a wall that is specified in an enumeration. There may be a property set given specifically for the predefined types.
NOTE  The PredefinedType shall only be used, if no IfcWallType is assigned, providing its own IfcWallType.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 IfcWallType is associated), or the inherited attribute ObjectType shall be provided, if the PredefinedType is set to USERDEFINED.
CorrectTypeAssigned : Either there is no wall type object associated, i.e. the IsTypedBy inverse relationship is not provided, or the associated type object has to be of type IfcWallType.

Inheritance Graph:

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;
PredefinedType : OPTIONAL IfcWallTypeEnum;


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