Underlayment | GCP Applied Technologies

GCP Applied Technologies has two new synthetic roofing underlayments. Tri-Flex XT is an alternative to #30 roofing felt, with an improved slip-resistant coating for foot traction. It can be exposed for up to six months, and a 10-square roll weighs just 28 pounds and covers five times the surface area as a 60-pound roll of #30 felt, the manufacturer says. Designed for use under asphalt shingles, Tri-Flex 15 is 10 times stronger than #15 felt, for added prevention of blow-offs and tears, and has a 60-day exposure limit to give builders added scheduling flexibility. Both products are 100 percent recyclable.