Invalid IFC 4 export result of window surfaces

[FranziWM]

I created a building with a few windows in Revit. After exporting the project to IFC4, the window surfaces are incorrectly exported as door surfaces. I opened the IFC file in ORCA AVA and Solibri. See in the attached JPGs.

[AngelVelezSosa]

I don't understand the issue. Isn't "fenster" a window? What is a window surface vs a door surface? IFC isn't smart enough to mis-categorize a door or window...

[lejla-adsk]

Hi @AngelVelezSosa,
I was also in contact with Franzi, maybe I can help explain the actual problem: the windows are actual windows in Revit, but in Solibri and OrcaAVA the window sill is ignored and the window geometry is extended to the floor (as if they were doors).
In FZK Viewer and BIM Vision the windows are displayed correctly and have a regular window sill

I couldn't find anything odd in the Revit families which would explain this behavior, and also FZK viewer doesn't show any "ghost" geometry below the window - any clue where Solibri (and obviously the ORCA AVA IFC Viewer) get the wrong geometry from?

Thanks,
Lejla

[AngelVelezSosa]

What happens when you link it back into Revit?

[guenter1holzeder]

Hi @lejla-adsk
Your comparison with FZK Viewer lags. There are two different geometries we have to regard: geometry of IfcWindow and ConnectionGeometry of IfcRelSpaceBoudary. With first one, shown by the FZK Viewer, there are no problems. We are talking about the ConnectionGeometry of IfcRelSpaceBoudary which is a shape geometry of the IfcRelSpaceBoundary instance (e.g. wall area).
Guenter

[AngelVelezSosa]

OK, so that is a question of what Revit is generating as the rel space boundary. Was that a 1st level or 2nd level space boundary? Do you get different results depending?

[guenter1holzeder]

Hi @AngelVelezSosa
There are only 1stLevel space boundaries

[AngelVelezSosa]

Can you try 2nd level?

[JOuellette-Autodesk]

@FranziWM and @lejla-adsk

What version of Revit? What version of the IFC Export Add-in?
Can you send the file to me so I can test in a couple of other apps and inspect it?

[FranziWM]

@JOuellette-Autodesk
I use Revit version 23.1.10.4 and IFC4 Reference View. Attached you can find the sampel files (Revit file, IFC 1st level and IFC 2nd level)

Sample files.zip