Gardner FGUR20 Roofing Felt, 72 ft L, 36 in W, Asphalt. 30# Felt H/D Asphalt Astm D226. This product is applied directly to the roof deck on sloped roofs and used under asphalt shingles, wood shakes and tiles. This product acts as a secondary layer of protection from wind driven rain, ice damming and normal weather patterns. The reason for the success is due to the products ability to shed water off roofs and protect the underlying building from water damage. The product also has the unique ability to "breathe" and let interior moisture escape the building. This is our highest quality asphalt roofing felt. This is our heaviest reinforced mat that is saturated with premium-grade asphalt to provide the ideal roofing underlayment. The rolls are heaviest, due to the thick reinforcing mat and high content of asphalt.