INQ:

### Inquiry description

Is it possible to push a material name from a system family layer structure to a certain parameter with the use of parameter expression?
https://github.com/Autodesk/revit-ifc/wiki/Revit-IfcExporter-parameter-expression
And if it is possible with what specific code?


A contractor wants to read all the materials in the custom family layer structure in it's own Pset.
I can fix user families. I can fix a structural material parameter. But i cannot get the rest of the materials located in the layer structure of system families.

### Revit Version

2024.3.x

### IFC for Revit Addon Version

24.3.2

### Windows Version

11 24H2

Start with the Revit-IfcExporter parameter-expression wiki page and the attached example; investigate whether system-family layer materials can be referenced for Revit 2024.3.x and IFC 24.3.2. Done means documenting a supported expression or establishing that this capability is unavailable.

Written by the indexing model from the issue text.