IfcWallStandardCase
Definition from buildingSMART: The standard wall (IfcWallStandardCase) defines a wall with certain constraints for the provision of parameters and with certain constraints for the geometric representation. The IfcWallStandardCase handles all cases of walls, that are extruded vertically
and have a single thickness along the path, i.e.:
The following parameter shall be given:
The material of the wall is defined by the IfcMaterialLayerSetUsage and is attached by the IfcRelAssociatesMaterial objectified relationship. It is accessible by the inverse HasAssociations relationship. The material layer set usage has to be given (enforced by where rule).
HISTORY New entity in IFC Release 2x.
Type Use Definition
The type information relating to the IfcWallStandardCase is defined at the supertype IfcWall. As an additional use agreement for standard walls, the IfcWallType should have a unique IfcMaterialLayerSet, that is referenced by the IfcMaterialLayerSetUsage assigned to all occurrences of this IfcWallType.
 Assignment of IfcMaterialLayerSetUsage and IfcMaterialLayerSet to the wall type and the wall occurrence. 
Property Set Use Definition:
The property sets relating to the IfcWallStandardCase are defined at the supertype IfcWall.
Quantity Use Definition:
The quantities relating to the IfcWallStandardCase are defined at the supertype IfcWall.
Geometry Use Definitions:
The geometric representation of IfcWallStandardCase is given by the IfcProductDefinitionShape, allowing multiple geometric representation. Included are:
Local Placement
The use of local placement is defined at the supertype IfcWall.
Geometric Representation
The standard geometric representation of IfcWallStandardCase is defined using the following multiple shape representations for its definition:
First representation: Curve2D representation of wall axis
The wall axis is represented by a twodimensional open curve within a particular shape representation. The wall axis is used to apply the parameter to the wall geometry. The following attribute values shall be used
IfcShapeRepresentation shall have the following values:
 RepresentationIdentifier : 'Axis'
 RepresentationType : 'Curve2D'
Second representation: SweptSolid or Clipping representation of wall body
The body of the IfcWallStandardCase is defined by using 'SweptSolid' representation for walls without clippings or 'Clipping' representation for walls with clippings (e.g. under sloped roof slabs).
IfcShapeRepresentation shall have the following values:
 RepresentationIdentifier : 'Body'
 RepresentationType : 'SweptSolid' or 'Clipping'
SweptSolid representation
The standard geometric representation (for body) of IfcWallStandardCase is defined using the 'SweptSolid' representation. The following additional constraints apply to the swept solid representation:
The advanced geometric representation (for body) of IfcWallStandardCase is defined using the 'Clipping' representation. The following additional constraints apply to the swept solid representation:
EXPRESS specification:

WR1  :  The IfcWallStandard relies on the provision of an IfcMaterialLayerSetUsage. 
