I'm building a small modern house where the ceiling is essentially just two triangles. This makes it really hard to add edge loops and assign materials to different parts of the object. Is there a way I could model the structure so it's still comprised of quads?
This is not conventional and may have consequences on the topology, but what can be done:
Select the wall bottom edges and subdivide them by 2. So that you have.
Join the vertices (select them 2 by 2 then J key).
Select each edge and push it to the border using GG (twice).
Now you can: