Autodesk
PR: Exporting glazed roofs as IfcElementAssembly: Regression in 25.4.3
Problem Description
25.4.0 export behaviour
With the the 25.4.0 exporter we were able to export glazed roofs as IfcElementAssembly entities (one use case being elemented ceilings, i.e. the curtain panels are classified as IfcCovering entities). Revit would export this neatly both for IFC2x3 and IFC4:
25.4.3 export behaviour
The 25.4.3 exporter shows a different behaviour.
IFC2x3
For IFC2x3 it doesn't export a usable object.
In Solibri no entity is visible in the model structure:
In BIM Collab Zoom there is an entity visible in the model structure but it does not show any geometry:
There are mulitple validation errors for this entity ("Number of elements (0) violates aggregate bounds") - possibly the reason why the viewers can't display nay geometry?
IFC4
For IFC4 it still exports an IfcElementAssembly, but it is not composed by the individual panels anymore, i.e. not exported as an aggregate. The geometry is still there (but seemingly defined as the geometric representaton of the assembly itself).
Revit Version
2025.4.x
IFC for Revit Addon Version
25.4.0
Windows Version
11 24H2
Sample file: https://github.com/andydandy74/MyIssues/blob/master/RevitIFC893/187_IFC_GlazedRoofAsElementAssembly.rvt
This issue is also reported in Jira as "REVIT-240556" and is currently in the "Open" status.
