In my plan I need most of the foundation to be a monolithic slab except in areas where there are pipes such as the bathroom. I am trying to figure out how to cut a hole in a foundation that I have generated in CA with the foundation tool, but when I try the "slab hole with footing" and the "Hole in floor platform" tools I get errors. "could not create hole in floor platform" and "a slab hole must be placed inside a slab".
To elaborate on the foundation, it will be piers 4ft into the ground then a normal monolithic slab and footings will be poured on top of the piers. The footin