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

https://www.bookmark-maker.win/single-ply-roof-guarantees-often-cover-15-20-years-but-in-reality-these-roofs

Single ply roof guarantees typically cover 15-20 years, but the real service life can stretch to 25-40 years if properly maintained. Guarantees mostly protect against material failures, not wear and tear or damage from poor upkeep