Abstract: A building system that includes a plurality of screw piles (34, 36) positioned in the ground and one or more perimeter beams (16), wherein at least part of the perimeter beam (16) has a sloped lower surface (66, 68). The sloped lower surface of the perimeter beams (16) can divert swelling soils away from the perimeter beam (16). The swelling soils can be diverted into voids.

Abstract: The present invention relates to a screw pile comprising a shaft and at least two blades extending outwardly from the shaft. Each blade has a leading edge that contacts earth as the screw pile is screwed into the ground. The leading edge includes a swept back portion adapted to deflect rocks that come into contact with the swept back portion of the leading edge during insertion of the screw pile into the ground. In one embodiment, the leading edge of each blade includes two or more straight edge portions extending at different angles to each other. The straight edge portions may include an inner edge portion extending from the shaft and the swept back portion extending at an angle from the inner edge portion.