I would like to ask which is the actuall wall thickness according to the construction in a GBXML. For example if a wall Construction has layerIdRef="lay-ASHWL-66
and
<Layer id="lay-ASHWL-66">
<MaterialId materialIdRef="mat-AM13" />
<MaterialId materialIdRef="mat-AM13" />
and thickness of matAM-13 is 200mm?
That means that the wall thickness is 200+200=400mm?
Why matAM13 appears twice?
Thank you