You could model the mortar joints and such with a higher priority building material with a (complex profile) collumn. Make sure your precast concrete part of the wall is set up as 'core' and the walls as 'load bearing', make sure those collumns are set up as 'other' and 'not load bearing'. Now you can make elevations for 'core of load-bearing elements only' for the wall, where you would only see the pre-cast bits. However, once you go down that path, you'll probably notice that connection details for windows/doors etc etc are 'off' as well and it starts to be a lot of work to get things right.
If it were my project (as architectural firm), I'd supply some principle details of connections, model the wall as one complete bit of concrete, possibly showing some detail that makes sense up to 1:50 scale and check the production drawings from the factory before things are produced and not bother with doing their work. But maybe the Dutch construction marker differs a lot from yours.
Erwin Edel, Project Lead, Leloup Architecten
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