This specification covers Grades G (granule surfaced) and S (smooth surfaced) prefabricated bituminous sheet materials reinforced with polyester fabric and modified by styrene butadiene styrene (SBS) thermoplastic elastomer, intended for use in the fabrication of multiple ply roofing and waterproofing membranes. The sheet materials shall meet dimensional requirements such as thickness and net mass per unit area, as well as physical requirements such as peak load before and after heat conditioning, elongation at peak load, ultimate elongation, tear strength, low temperature flexibility, dimensional stability, compound stability, and granule embedment.

1.1 This specification covers prefabricated modified bituminous sheet materials reinforced with polyester fabric as the primary reinforcement, (see Note 1) with or without granules, which use styrene butadiene styrene (SBS) thermoplastic elastomer as the primary modifier and are intended for use in the fabrication of multiple ply roofing and waterproofing membranes.

Note 1: Many modified bituminous sheets are currently marketed with polyester mat reinforced with glass yarns to improve processing in the manufacture of the finished modified bitumen product and to reduce distortions that may be introduced during production. These glass yarns are typically a small percentage of the reinforcement and do not contribute to the physical properties of the finished product so much as to make these products be classified by Specification D6162/D6162M.

1.2 This specification is intended as a material specification only. Issues regarding the suitability of the specific roof constructions or application techniques are beyond this scope.

1.3 The specified tests and property limits used to characterize the sheet materials are intended to establish minimum properties. In-place roof system design criteria, such as fire resistance, field strength, impact/puncture resistance, material compatibility, uplift resistance, and others, are factors beyond the scope of this material specification.

1.4 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.