Assemblies

Definition

The IfcElementAssembly represents complex element assemblies aggregated from several elements, such as discrete elements, building elements, or other elements.

According to the IFC documentation, the IfcElementAssembly is an aggregate i.e. being composed by other elements and acting as an assembly using the objectified relationship IfcRelAggregates, referring to it by its inverse attribute SELF\IfcObjectDefinition.IsDecomposedBy. Components of an assembly are described by instances of subtypes of IfcElement. In this case, the contained subtypes of IfcElement shall not be additionally contained in the project spatial hierarchy, i.e. the inverse attribute SELF\IfcElement.ContainedInStructure of those IfcElement's shall be NIL.

The assembly structure can be nested, i.e. an IfcElementAssembly could be an aggregated part within another IfcElementAssembly.

Relation to the Recycle, Reuse and Repurpose potential

Assemblies play an important role in the reuse potential of a building. Reuse implies that an element can be either reused as such or disassembled in its consituents parts and that these parts can be reused in another building or for another purpose.

There are many standardized property sets such as e.g. Pset_EnvironmentalImpactIndicators. Additonally custom properties can be added as needed.