Design > Update Zones
Make sure you use 'Inner Edge' as your zone polygon method. This will drop a moveable hotspot / point in your room and from this point it will find edges when you update the zone. These edges are called zone boundaries. Many different 3D elements can be boundaries (walls, collumns, curtainwalls, etc) but also 2D lines. The elements need to be visible (layer on) for this to work.
This is a very basic question. You might want to consider a training course to get you up to speed with ArchiCAD quickly
Erwin Edel, Project Lead, Leloup Architecten
www.leloup.nlArchiCAD 9-26NED FULL
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