How to make roof in layer

Don’t do this!!! It will result in the geometry of the roof being in a separate layer. Which is NOT a good idea and is exactly what SU recommends you NOT do.

Frankly, I’m surprised that a SU Tech Support person recommended this.

If you have already created the roof, then here’s another way to get it (but not it’s geometry) into a separate layer:

  1. Make sure that the geometry of the roof is in one or more groups (or components).
  2. Create the “roof” layer (if you haven’t already)
  3. Select the group(s). In the entity window, choose “roof” in the Layer field.

There are a lot of threads that emphasize the problems of drawing geometry anywhere other than layer0, such as:
Keeping Geometry Separate
Layering Mistake - any way to systematically fix?