For builders who want to create a high-performance building envelope, Foam-Control Max from ACH Foam Technologies could be the solution. The graphite polystyrene (GPS) rigid foam insulation achieves an R5 R-value at 1 1/16 inches thick. Made of small pockets of air within a polymer matrix, the graphite reflects radiant heat energy, which increases the material’s resistance to heat flow. Foam-Control Max has an increased R-value as the outside temperature drops. The semipermeable material allows vapor to pass through for moisture resistance and permeability. It is produced in three grades, 100, 150, and 250, and the manufacturer says it has a 30 percent material savings cost over extruded polystyrene (XPS).
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