Abstract: A prefabricated wall forming structure for constructing reinforced concrete walls employs insulating foam plastic panels that are interlocked into two parallel concrete impervious walls by connectors having two I beam channels that are spaced apart by tie elements having an arcuate cross section. The tie elements support reinforcing bars. The I beams may have striated outer faces to hold stucco and plaster. The web of at least one of the I beams may have an elongate channel or raceway for wires and pipes. Connectors may be applied vertically and horizontally to seal all edges of the panels and resist the hydraulic forces of the poured concrete. The connectors and panels remain in place after concrete is poured to create an insulated concrete wall. A method of extruding the connectors uses an intermittently opening and moving die passage to create the tie elements and the I beams in one continuous process.

Abstract: A prefabricated wall forming structure for constructing reinforced concrete walls employs insulating foam plastic panels that are interlocked into two parallel concrete impervious walls by I beam channels that are spaced apart by tie elements. The tie elements can support horizontal or vertical reinforcing bars and prevent the foam walls from spreading apart under the hydraulic force of the poured concrete. The I beams snugly engage the edges of the foam panels to provide a concrete imprevious seal and align the panels vertically and horizontally. A corner connector performs a similar function.

Abstract: An insulated building is constructed of panels that have a rigid, closed cell foam sandwiched between, and bonded to high tensile strength outer sheets. The outer sheets extend beyond the edges of the foam to provide grooves along the edges of the panels. The panels are joined together by elongate edge connectors. Each edge connector is formed by extrusion of a high tensile strength outer layer enclosing a rigid foam core. From the central body of the edge connector, tongues extend out at fixed angles corresponding to the angle between panels. The tongues are bonded into the grooves in the panel edges. End connectors fit telescopically into the ends of adjoining edge connectors and are bonded in place to form an integrated frame interlocked with the panels.