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

https://melissafreshmaid.com/tpo-vs-pvc-lifespan-what-matters-more-than-the-material/

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