15# ASTM D4869,36''X144' 15# ASTM D226,36''X144' 30# ASTM D4869,36''X72' 30# ASTM D226,36''X72' roofing underlay ASTM D-226 15# roofing underlayDescription:A heavy-weight asphalt roofing felt made of a specially formulated organic sheet which has been fully saturated with waterproofing asphalt.Uses:A roofing felt used as an underlay beneath asphalt shingles, wood shakes, tiles and other sloped ...