Black Diamond® Base Sheet is a heat-activated, self-adhered base or interply for hybrid roof systems with a torch-applied cap or cap set in hot asphalt for modified bitumen or built-up roofing systems. This 55 mil membrane is manufactured with tough, dimensionally stable fiberglass reinforcement saturated and coated with SBS-modified bitumen, offering exceptional durability. It is suitable for use in both new construction and reroofing over a variety of substrates, including but not limited to insulation, concrete and plywood/OSB. Black Diamond® Base Sheet is Green Circle Certified with 24% recycled content. Black Diamond® Base Sheet delivers measurable labor savings over traditional fully adhered asphaltic membranes without compromising waterproofing protection. Black Diamond® Base Sheet also may be used as a vapor retarder under roof insulation and may be left exposed for up to six months without asphalt degradation. This versatile base ply can be used in CertainTeed two-ply, low-sl...See Moreope roofing systems for up to 31 1/4 - year warranty durations for Credentialed Contractors when paired with a CoolStar® cap sheet Reach out to your local CertainTeed Territory Manager to request a sample and demonstration of Black Diamond® Base Sheet. See Less