SBS polymer-modified base sheets should not meet or exceed the requirements of which standard?

SBS polymer-modified base sheets should not meet or exceed the requirements of which standard?

• A. ASTM D1970
• B. ASTM D6162
• C. NRCS D6162
• D. ANSI D6162

Answer: (B)

SBS polymer-modified base sheets are a different class of base sheet than traditional asphalt-saturated felts. They incorporate polymer modification in the bitumen, which changes their performance characteristics and the test methods used to specify them. ASTM D6162 is the standard that covers conventional asphalt-saturated felts used as a base for built-up roofing, and its criteria don’t apply to these modified materials. Because of that, SBS polymer-modified base sheets should not be expected to meet or exceed D6162 requirements; they are governed by standards written for modified bitumen products, not the conventional felt criteria. The other standards listed are not applicable to this product category in the same way.

SBS polymer-modified base sheets are a different class of base sheet than traditional asphalt-saturated felts. They incorporate polymer modification in the bitumen, which changes their performance characteristics and the test methods used to specify them. ASTM D6162 is the standard that covers conventional asphalt-saturated felts used as a base for built-up roofing, and its criteria don’t apply to these modified materials. Because of that, SBS polymer-modified base sheets should not be expected to meet or exceed D6162 requirements; they are governed by standards written for modified bitumen products, not the conventional felt criteria. The other standards listed are not applicable to this product category in the same way.