GAF Materials Corp.
EnergyGuard HD is a half-inch thick, high-density polyisocyanurate (ISO) cover board with an R-value of 2.5. The HD version provides over 80 psi compressive strength and weighs 11 lbs. per 4-by-8-foot board. HD PLUS offers over 110 psi and weighs 13 lbs. Each has a coated glass facer and can be used as a protective layer over boardstock insulation or as a recover over an existing roofing system.