Building blocks

A building block comprising a six-sided, parallelepiped body formed of rigid, foamed resinous material having thermal insulating and fire retardant properties, said body having flat upper and lower surfaces, flat opposite ends, and laterally extending, convex projections at two opposite sides;

• a pair of masonry slabs each of which has an inner, concave surface and an outer surface;
• and means securing said slabs to said body on said opposite sides of the latter with the inner surfaces of said slabs embracing said projections and adhered to the respective opposite sides of said body, said slabs having external, parallel, bottom grooves extending the full length of the lower surface of said body and external, parallel, end grooves extending the full height of one end of said body, with the bodyportion forming part of the end and bottom groove said slabs having integral, external, parallel, top ribs extending above and along the upper surface of said body a distance corresponding to the depth of the bottom grooves adjacent the lower surface of said body, said ribs extending beyond the other end of said body a distance corresponding to the depth of the end grooves adjacent said one end of said body, said slabs having parallel, external end ribs adjacent said other end of said body projecting beyond the latter a distance corresponding to the depth of the grooves adjacent said one end of said body, the relative widths of and spacing between the end grooves and the end ribs at opposite ends of said body and the top ribs and the bottom grooves at the respective upper and lower surfaces of said body being such as to enable the end grooves at said one end of said block to accommodate and abut the end ribs at the other end of a like block and the bottom grooves at the lower surface of said block to accommodate and abut the top ribs at the upper surface of a like block, said body being located wholly within the confines of said slabs.