The Insul-form Building System, developed in Canada, is an insulating concrete form system made up of large expanded-polystyrene panels each with an outer layer of oriented strand board (OSB). The strand board not only strengthens the form, it provides a continuous substrate for installation of interior and exterior finishes. The form panels are connected by flat ties designed for break-back after the concrete cures. When filled with concrete, Insul-form produces a wall with insulation values of R 18 to R 34.
The form panels come in standard sizes of 2x8 or 4x8 feet and have 2-inch-thick foam insulation backed by 19/32-inch-thick OSB. This standard form configuration produces a concrete core 8.3 inches thick. With the OSB left in place, the total wall thickness is 13 ½ inches. By changing the insulation thickness or ordering a different tie length, any desired wall section can be produced. Easy-to-assemble corner forms speed erection of the system, and notched ties are designed to go through predrilled holes in the OSB. Tie ends are pointed so they can punch through the insulation layers. Spreaders maintain the proper distance between the insulation faces of the forms.