Solid Tools for Mansard & Dormer poke thru

I’m looking for some help from you pros. I’ve researched the Solid Tools and I’m not sure which would be best in my model. I drew a mansard roof and the dormers that pop thru the roof. Should I subtract the roof from the dormer walls. Thank you.

Do you want the dormer walls to remain separate from the roof? Or do you want them to be combined? I’d be inclined to combine them with Union or Outer Shell. If you want them to remain separate from the roof, I would Trim them dormers with the roof.

I figured I should keep them separate but I don’t really know if I have a good reason to do so. I’m still pretty new to constructing a model. Are there pros/cons to combine vs trim? Thank you.

I think in a model like you show maybe the pros to leaving the dormers separate and just trimming them to the roof would be you could use multiple instances of a single dormer component so if you add details like windows and materials, you can edit one and take care of all of them in one swell foop. The other benefit is if you want to show the roof without the dormers, that’s easier to do because the dormer components could have a “dormer” tag" while the roof has a “roof” tag. Then if you turn off the visibility of the dormer tag, you have only the roof to look at.

Good points. Thx.
I hadn’t thought of making a dormer a component…that’s a great idea.

If you were going to merge the dormers with the roof it probably doesn’t make a lot of difference whether you make them a group or groups or make a component of a single dormer. I like to think as far ahead as I can when modeling so in something like you’re doing, I’d make the dormer a component and copy it around the roof and leave them as they are until the rest of the modeling is basically complete and the textures added. Basically I’d wait until the last minute to lose their component-ness to save myself as much repetitive work as possible.

FWIW, if you were going to leave them separate from the roof anyway, it wouldn’t really matter if you trim them off to the curve of the roof. In fact it might go a little way toward keeping file size down if you don’t trim them because of the reduced number of edges and faces.

Quick example with 22 entities on the left and 42 on the right.

You are right, in fact, this idea was patented some 20 years ago: