摘要 |
A roofing shingle includes organic, resinous material and an inorganic filler material, the single having a top surface, two side surfaces, an upper end, and a lower or butt end, defining a cavity on the underside of the shingle, with ribs positioned within the cavity. When applied to a roof, the shingle has the appearance of wooden shake shingle and provides a Class A fire barrier when tested according to ASTM test E108-93 for flame spread, burning brand and intermittent flame. |