https://community.graphisoft.com/t5/Collaboration-with-other/Property-Manager-Expression/m-p/237234#M30478 NO<BR /> <BR /> Expression can only address one element at a time - the one their connected to. You could obtain the net surface area of a wall but that would exclude all the windows and door openings.There is no way to exclude certain openings now. Fri, 24 Aug 2018 16:01:38 GMT poco2013 2018-08-24T16:01:38Z https://community.graphisoft.com/t5/Collaboration-with-other/Property-Manager-Expression/m-p/237233#M30477 <DIV class="actalk-migrated-content"><T>Hello everyone<BR /> <BR /> I am not sure if this is possible and I am struggling with expressions.<BR /> <BR /> Is it possible to get all windows that start with a particular ID and the walls they are associated with to work out the % of window area to wall area?<BR /> <BR /> Cheers<BR /> <BR /> Dan</T></DIV> Fri, 24 Aug 2018 11:02:22 GMT https://community.graphisoft.com/t5/Collaboration-with-other/Property-Manager-Expression/m-p/237233#M30477 Anonymous 2018-08-24T11:02:22Z https://community.graphisoft.com/t5/Collaboration-with-other/Property-Manager-Expression/m-p/237234#M30478 NO<BR /> <BR /> Expression can only address one element at a time - the one their connected to. You could obtain the net surface area of a wall but that would exclude all the windows and door openings.There is no way to exclude certain openings now. Fri, 24 Aug 2018 16:01:38 GMT https://community.graphisoft.com/t5/Collaboration-with-other/Property-Manager-Expression/m-p/237234#M30478 poco2013 2018-08-24T16:01:38Z