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

https://landenuzqb895.theglensecret.com/what-parts-of-a-membrane-roof-usually-fail-first

Single ply roof guarantees often cover 15-20 years, but the real service life can stretch 25-40 years if the roof’s properly looked after. Guarantees focus on material defects, not wear and tear or maintenance issues