Duro-Last

Duro-Last is a US manufacturer of single-ply roofing systems, best known for PVC membranes that are custom-fabricated in the factory into large deck sheets sized to a specific roof. It is headquartered in Saginaw, Michigan. Holcim's building envelope business acquired Duro-Last in 2023, and since Holcim's North American spin-off in June 2025 it has been a brand within the Building Envelope division of Amrize.

History

The company's founder, John R. Burt, started the business at the age of 58. Its predecessor, Tri-City Vinyl, was incorporated in 1977 to make swimming-pool liners. The Duro-Last roofing system was developed and first installed in 1978, and Duro-Last itself was incorporated in 1981. It bought its first Saginaw facility in 1982 and added a second there in 1984.

Further plants followed in Jackson, Mississippi (1994, about 7,400 m2 / 80,000 sq ft); Sigourney, Iowa and Grants Pass, Oregon (1996); Carrollton, Texas (2013); and Ludlow, Massachusetts (2017). A Largo, Florida site opened in 2023 as its seventh manufacturing facility and a Kernersville, North Carolina plant of about 9,700 m2 (104,000 sq ft) in 2025 as its eighth. Texas operations moved to a larger facility in Dallas in 2025. The company also opened a screw manufacturing operation in Oscoda, Michigan in 1999, and acquired ANViL Paints & Coatings in 2016.

Products

Prefabrication is the company's distinguishing approach: seams that would otherwise be welded on the roof are heat-welded in the factory, and flashings for pipes, curbs and corners are made to measured dimensions, reducing rooftop seaming. Duro-Last uses its own PVC extrusion. Its range also includes TPO membranes, roll goods, metal roof and wall panels, insulation and cover boards, vapour barriers, skylights and coatings.