I have recently done this using the new component-level type mapping in Archicad 26.
For IfcWall, IfcSlab, IfcBeam, IfcColumn and IfcStair I added a new IFC Property Component_ID defined as IfcLabel.
I created a new component based rule and added content to map the IfcLabel to the Element_ID of the component.
The IFC export will now contain the Element_ID of the component for the decomposed parts.
In Solibri the wall shows the Element_ID under Identification - Name
When selecting a decomposed part of the component the Element_ID will be shown in AtCo_IFC-Properties as the value for property Component_ID
So now you can easily generate ITO's for a specific building material with relation to the component it is part of.
I hope this helps!
If it does please mark this post as a solution (accept as a solution).
BIM Modeller at Atrium Architecten
Archicad user since April 2014 (v17 - v25) - CC iRT i9-12900 - 64 GB / Nvidia Geforce RTX 3080 - Windows 10 Pro 64
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