I ended up modelling the insulation seperately last time around, but there was no demolishing of the existing facade underneath. There were some minor issues with two walls touching and archicad interpreting the cutlines where they touch as skin seperators, mostly to do with how we override the model views (graphic overrides / renovation filter settings).
Wall holes and wall niches sometimes help with 'demolishing' partial bits of walls. Just place these as 'new' elements and they will show up as bits that need to be demolished.
Erwin Edel, Project Lead, Leloup Architecten
www.leloup.nlArchiCAD 9-26NED FULL
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