Many times we have conditions like the one in the image above where a masonry wall with furred out studs extends across an opening, ending perpendicular to another wall. The opening is created using an empty window or door. The other way of achieving it is to build two separate walls (one for the full exterior wall and one for the header wall above the opening). Using the first method, typical wall type (CMU + furring) creates a false corner condition, showing furring studs intersecting the masonry corner. My suggestion is to build two separate walls, one CMU and one for the furring wall. This way we have better control of these conditions. Another example is when using a wall type that includes both and in the building section shows the furring extending pass the roof surface all the way to the top of the parapet.
I believe that the BIM experience should go parallel to the construction methods and procedures. In other words, when we are modeling, we are really building in the field. Masonry goes first, furring is added later at the interior. Unfortunately, BIM softwares don’t give us the flexibility to control wall layers individually in a wall composite. Please let me know if there is a way!!! Otherwise, using some of these standard composite wall types will continue creating confusing drawings that are not communicating correctly the design intent.
Thoughts?
It seems like you are on the right track. There is not a good way to do this with Composites. One thing you might try is a tip from this blog…
http://www.onland.info/archives/2010/07/fixing_wall_corners_with_columns.php
If I’m understanding this correctly, I would think that editing the Composite so that the Intersection Priority setting for the masonry is higher than the furring. Unfortunately, for this to work automatically between multiple Composites, someone would have to go through all of the Composites in the template, and set a universal priority for each material (i.e. all masonry might be #9, while drywall is #8, and studs or insulation is #7). I generally just make adjustments when I have a problem, but unfortunately, sometimes that causes a new problem somewhere else in the plan. So when that “voodoo” won’t work, you’ll have to turn to the column trick that Matt posted.
We can also show different views using the Partial Structure Display, which can strip away non-structural furring layers (as long as the stud space is marked in the composite as non-structural, which may involve editing). This could be useful when creating drawings for a shell and TI at the same time. However, there’s nothing wrong with using different walls for furring, but it takes some double-checking to avoid misplacement.
One other suggestion for the furring/parapet paradox: it is typically better to copy a new exterior wall on each story, rather than using a multi-story wall (like virtual platform framing vs. balloon framing). This was once the only way to do it in ArchiCAD, and it still responds the best in my experience. This is especially important at the parapet; stop the exterior wall height at the top of the furring, and start a new parapet wall (bottom to match, which may be below the actual Roof level). Then it will look right in section, plus it gives you more freedom to adjust the 2D appearance of the parapet. Think of this as building the exterior wall in lifts that correspond with the furring. This all be even easier in AC17, where we can finally set wall height relative to story height. Complex Wall Profiles could also be used, but that could get, well, complex.