Level design: Bottom floor best practices

I’m a sound designer who’s dabbling in the rest of game development as a way to learn new skills and make myself more valuable to a team. Recently, I’ve been doing a lot of really basic level design in Blender, and I was wondering what the best practice is for the bottom level.

Should I fill in the floor, essentially, with vert-by-vert polys, or should I place a single plane that will intersect the walls a little bit (for a clean edge)? Or am I splitting hairs over too few faces to matter?

For sure you don’t want one super huge floor covering the entire level, because it would prevent occlusion to work, it would probably make every light affect your floor and other things like that.
you can have a plane for each room or whatever, the level of detail of the plane will depend on a couple things, I think a higher poly count will let your scene lights affect the floor better, I could be wrong though. Best way is to try it.

Another thing to keep in mind in general when you’re doing level design, it’s too build your assets on a grid, meaning everything has a size that is a factor of X, I’ve read many thimes that the standard was making your objects factors of 32 units, but not sure why that arbitrary value, might have to do with texture size.