IFC export of Spaces information

I noticed something related to spaces' properties export to IFC 4 that doesn't make much sense in my opinion. Maybe someone can explain why it is like this.

The IFC element type "ifcSpace" has some attributes related to space naming:

  • Name
  • Description
  • LongName

When exporting from OBD it looks like the properties "Space Number", "Label" and "Label2" are used to populate those ifc attributes. However it's not a 1-to-1 mapping:

  • ifc attribute "Name":
    • Favours "Space Number" if it has a value
    • Takes the value from "Label" otherwise
    • If neither "Label" nor "Space Number" are populated in OBD it gives the value of the catalog "Instance Name"
  • ifc attribute "Description":
    • Takes it value from "Label" if it has a value
    • Will display the element ID and model name otherwise (for example '86568.82029*ARCH - Design!10_Gelijkvloers')
  • ifc attribute "LongName"
    • Equals "Label2" if it has a value
    • Equals "Label" otherwise

It appears to be very confusing at first glance. I fail to see the logic for "Description" and "LongName". I'd expect the LongName to look at "Label" first, and description to use "Label2". Or is this just me?

When creating spaces from the Program Manager only the value for "Label" is populated. I'd expect the space number to be equally important (or even more important) since it's the unique identifier, right? Is there a way to number them chronologically based on the program manager? Maybe for each "group" in the program manager set a prefix, for example "0." for ground floor, ...?