OptionalaggregatedFacilities that are part of the facility (e.g. when a building is a complex of buildings)
OptionalaggregatedDistinct parts of the facility (e.g. storey or railway part)
OptionalaggregatedSpaces in the facility that do not belong to a facility part
Type of facility (e.g. IfcBuilding)
OptionalelementUnique identifier for the building
OptionalnameOptionalproperty
Facility (e.g. building or bridge)