WeatherLock Mat is a polymer modified bituminous sheet material intended for use as underlayment. Underlayment is manufactured as a fiberglass mat surface impregnated and coated with a self-adhering modified asphalt. Underlayment rolls have approximate dimensions of 66.7ft x 3ft. Underlayment is self-adhered.
Product has met specification requirements of ASTM D1970.
ASTM E108 (Fire)
Product has met Class A requirements of ASTM E108 when installed over minimum 15/32in thick APA-rated plywood decks with allowable roof covers of asphalt shingles (ASTM D3462) or slate shingles (ASTM C406). Slope is unlimited.