buildingSMART Forums

Is there anything determining external / internal face of walls, or for material layer set usages?

For a wall in particular, perhaps one with IsExternal set to true, is there something which determines which side of the wall is external facing and which one is internal?

For any other object, is there anything which assigns the semantic of “external” vs “internal” facing material in a material layer set usage?

Not to my knowledge. Extending on the discussion here [0] you could use the geometry of spaces (or space boundaries) and overlay them with wall/slab geometries separated by material layer as you obtain them from IfcOpenShell.