Where I live, in the mountains of Southern California, just about every building site is sloped. In 30-odd years of building foundations here, working on hillsides has become second nature to me. In this climate, the ground never freezes more than a few inches deep, so there's no need for a deep frost footing. On flat sites, all you need is a shallow trench around the perimeter of the building, a simple perimeter form, and you're ready to pour the slab and footing in one shot (see "Monolithic Slabs on Grade," 3/95). On many sloped sites, we do much the same thing on the side of a hill. We build stemwall
