Abstract: A method of forming a panel structure useful in building construction and the like includes the steps of heating a heat expandable plastic in a separable mold having a cavity with the configuration of the resultant panel to form a panel core and adhering thin reinforcing strips to the front and back surfaces of the core. Control over the dimensions and configuration of the panel is obtained by adhering the strips to the core in the mold while applying heat thereto whereby core shrinkage is minimized. The strips may be adhered to the core during initial heating of the plastic material to form the core or may be adhered to the core in the mold subsequent to core formation.

Abstract: A building panel has an expanded plastic core with thin reinforcing strips bonded to front and back surfaces of the core, at least along the edges thereof, and may have a wire grid attached in offset relation to one surface thereof for receiving a material such as concrete. The panel is manufactured by a process of expanding a plastic material in a mold by the application of heat to form a core, removing the core from the mold, placing thin reinforcing strips on front and back surfaces of the core with an adhesive system between strips and core, returning the core to the mold and heating the interior of the mold to bond the strips to the core and achieve dimensional stability during molding.

Abstract: A system of constructing buildings by connecting together expanded plastic panels with reinforcing strips bonded thereto and wire mesh attached to the exterior surfaces thereof upon a foundation with at least a portion of the panels having a curved configuration to maximize structural strength of the combination of panels. Concrete is applied to the exterior of the combined panels with the wire mesh then forming reinforcing in the resultant concrete wall upon the panels and the interior is coated with plaster to form a low cost structure with very good insulating properties.