Single-ply roof guarantees typically cover 15-20 years, but a roof’s real...

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

Single-ply roof guarantees typically cover 15-20 years, but a roof’s real service life can stretch to 25-40 years with proper care. The guarantee mainly covers materials and workmanship, not wear and tear or maintenance issues