Abstract: An insulated concrete slab assembly for use over expansive soils. A slab is cast in place by pouring concrete into preshaped insulating forms. The forms remain permanently in place and provide insulation to reduce heat transfer through the slab. The shape of the forms provides strengthening ribs on the slab. The ribs act as beams which allow the slab to bridge or cantilever over expansive soil between foundation walls. The forms are supported during construction by support members or legs which later prevent damage to the slab by eliminating or limiting the forces which can be applied to the slab by expanding soil.

Abstract: A insulating foamed polymer wall panel comprising a sheet of foamed polymer having sizable dimensions to form a substantial part of a wall when assembled. Adjacent wall panels are coupled using splines which, together with the side edges of the panels, form the sidewalls of a cement channel between the panels. The panel has connecting slots for receiving the splines and a plurality of edges, each top and side edge having a longitudinally extending groove to accommodate the fill of cement therein. The grooves provide tongue-and-groove connections between the cement post and adjacent wall panels once the cement has set, thus locking the latter into place.