Single ply roof guarantees often promise 15-20 years, but the real service life...

https://www.bust-bookmark.win/single-ply-roof-guarantees-typically-15-20-years-cover-defects-but-not-the

Single ply roof guarantees often promise 15-20 years, but the real service life can stretch to 25-40 years if looked after properly. These guarantees cover material defects, not wear and tear from weather or poor maintenance