As well as adding planar objects to your slabs or subtracting planar objects from your slabs, you can also add or subtract 3D objects. In the image above you’ll see that I subtract a tapered extrude from my slab to create a set down and then I add an extrude along a path to create my footing.
This is a very interesting item. I just wonder if adding or subtracting will mess with the hatch in plan and section as it happens to walls.
Can one add or subtract 3D from the bottom of the slab?
You should be able to add or subtract it from any part of the slab.