Products / Sharkskin Ultra

Sharkskin Ultra is Kirsch Building Products' original synthetic roof underlayment, brought to market in 2001 for use under battened and counter-battened metal, slate, tile and shingle roofs in new construction, remodeling and reroofing. It is a woven-polypropylene scrim with top and bottom polyolefin coating layers and a nonwoven, slip-resistant top surface, gray with blue printing, at a nominal weight of 4.8 lb per 100 sq ft. It installs with 3/8-inch roofing nails (no cap nails required), is rated for service between -40 F and 280 F, up to 12 months of UV exposure, and carries a 50-year warranty. ICC-ES ESR-1708 lists Sharkskin Ultra as an alternative to ASTM D226 Type I and Type II felt and states two mechanically fastened layers may serve as an ice barrier under the applicable IBC/IRC ice-barrier sections; the report also limits use to roofs of 2:12 slope or greater and to roof coverings mechanically fastened through the underlayment.