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

https://www.nav-bookmarks.win/single-ply-roof-guarantees-usually-cover-15-20-years-while-the-actual-service

Single ply roof guarantees usually cover 15-20 years, but the actual service life can stretch to 25-40 years with proper care. That’s because guarantees focus on manufacturing defects, not wear and tear or poor installation