Rmax Advantage Vented Nailable Base-3 is an energy-efficient thermal insulation board composed of a two-step system with polyisocyanurate (polyiso) foam insulation and a separate OSB nailing surface with furring strips attached. The insulation portion of this product is Rmax’s rigid environmentally sound closed-cell polyiso foam with glass fiber/organic mat facers on both sides. The standard nailing surface of Advantage Vented Nailable Base-3 is 7/16” OSB (APA rated). The venting pattern includes five (5) solid 1” thick wood furring strips. Alternate nailing surfaces, such as 5/8” OSB or CDX plywood, are available upon request, as well as, different thicknesses of vented air space. Advantage Vented Nailable Base-3 is applied to the roof structure in order to provide a layer of thermal insulation and a suitable substrate for the application of a variety of shingles available in today’s market.