Missing 2nd level space boundary information after exporting IFC from Revit

[Howie_Liu]

Hi, I am trying to get the IfcRelSpaceBoundary and IfcRelSpaceBoundary2ndLevel information for analysis. But it seems that the information is missing after exporting IFC from the Revit model.

I have the attached Sample.rvt Revit model with three rooms. Then I exported it into IFC with the Space boundary - 2nd level ticked, as shown in the attached 1.png. According to the IFC documentation about IfcRelSpaceBoundary and IfcRelSpaceBoundary2ndLevel, there should be 2nd level space boundaries in the IFC file. But it seems that such information is missing, as shown in the attached 2.png.

I also made the export phase the same as the phase of the room spaces according to the similar question here but it didn't work either. The Revit version is 2024. May I know how can we export the 2nd level space boundaries correctly in the Revit-IFC export settings? Thanks!

[marco_salvatoCD3KN]

Hi, I dont think I have an answer to your question, but maybe you could help with mine since its similar, I am trying to get the IfcSpace of an element using IfcOpenShell, but when use their method :

window= model.by_type("IfcWindow")[0]

ifcopenshell.util.selector.get_element_value(window, "space")

I get no output, so it seems that in my .ifc file and so I am guessing in the revit bim model (which i didnt model myself) there isnt a connection between an object and the room it is in. 

Any clue on how to fix this? Should any ifc exporting setting changed? or should i tell modelers to change something in the model or how they model? Thanks in advance