Products / AC Granular Ice and StormSeal

AC Granular Ice and StormSeal is a granular-surfaced, self-adhesive roof underlayment for asphalt shingle, wood shake and quarry slate roofs, made to protect against water entry from ice dams and wind-driven rain. It has a modified asphalt adhesive layer under a split release liner, is reinforced with a fiberglass mat, and its granular surface allows a maximum of 30 days of exposure. The April 2020 data sheet gives a nominal thickness of 46 mils in a 195 sq. ft. (3 ft. x 65 ft.) roll, a 2:12 minimum roof pitch and installation at 40 F and rising, while the maker's product page gives 50 mils in 100 sq. ft. and 195 sq. ft. rolls. The data sheet reports ASTM D1970 test results and lists Florida Product Approval and Miami-Dade County Product Approval.