You are using priority based connections, which means that those walls/collumns etc have a building material which has a higher priority than your roof currently has.
Either fix this or use Solid Element Operations instead of Trim.
Trimming is the more intelligent option where your walls and collumns would pass through the 'weaker' materials and stop at the 'stronger' core, provided you set this up correctly.
Solid Element Operations as the name implies just defaults to the solid elements (walls, roofs etc all are solids) as a whole to substract, interfere, exclude etc etc
Erwin Edel, Project Lead, Leloup Architecten
www.leloup.nlArchiCAD 9-26NED FULL
Windows 10 Pro
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