Single ply roof guarantees usually cover 15-20 years, but the real service life...

https://www.insert-bookmark.win/single-ply-roof-guarantees-usually-cover-15-20-years-but-the-actual-roof-can

Single ply roof guarantees usually cover 15-20 years, but the real service life can stretch well beyond that, often 25-40 years. Guarantees focus on material faults, while actual lifespan depends on maintenance, weather, and installation