The documentation for IfcMaterial states:
The Property Sets for Objects concept template applies to this entity as shown in Table 694.
I find this statement confusing, as
IfcMaterial is not a subclass of
IfcObject, and does not have any
IsDefinedBy attribute. Therefore, I see no way to apply a property set, such as
I believe the documentation should be amended to describe how
IfcMaterial can have property sets applied via the
HasProperties attribute and the
IfcMaterialProperties entity (which would replace
IfcPropertySet in the more traditional application).
Maybe this warrants a new page in chapter 4, perhaps called “Property Sets for Materials”, to remove the confusion.