Is there an 'empty' building material for the cores or is it just actual void? I've found it best to not draw profiles with holes in them, but to fill those holes up with empty fill materials. Holes really slow down performance and will show in these sort of instances.
Or you could do as suggested and model the side panels/trim (assuming they would be there).
Erwin Edel, Project Lead, Leloup Architecten
www.leloup.nlArchiCAD 9-26NED FULL
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