buildingSMART Forums

Spatial Decomposition concept definition

ifc4-errata
#1

Seems that there are some adjustments required for the concept “Spatial Decomposition” in the published schemas.

There is a note on this page:
http://www.buildingsmart-tech.org/ifc/IFC4/Add2/html/link/spatial-decomposition.htm

NOTE The link between the project and the highest level spatial element is provided by this concept through IfcRelContainedInSpatialStructure and not through declaration using IfcRelDeclares. This is a known anomaly intruduced to maintain compatibility with earlier versions of this standard.

Aside from the typo for “intruduced” it mentions the relationship IfcRelContainedInSpatialStructure that can’t be related to a project (only an IfcSpatialElement). It also seems to me that the concept is nominating the name attribute to be involved which seems incorrect.

#2

Thanks @jonm - it seems to be a mistake - the link between IfcProject and IfcSite (which normally is the highest spatial structure element) is handled by IfcRelAggregate. It should be corrected with the next documentation update.