Underlayment Specialties Plus (USP)

Underlayment Specialties Plus makes roofing and wall underlayments, including synthetic roof underlayments, self-adhered ice and water protectors, and breathable rain screen wall membranes. Its best-known lines are RoofTopGuard II Premium, Roofers Choice II Synfelt and RoofTopGuard SA, which roofing contractors use for protection under shingles and metal.

This is a manufacturer and distributor rather than a retail shop, so it serves contractors and builders. The company says it ships across North America from four main distribution facilities and works through hundreds of local and regional distribution points. Its corporate headquarters is at 1529 Gehman Road in Harleysville, with a second office in Lansdale.