Single ply roof guarantees typically cover 15-20 years, but the actual 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 actual service life can stretch up to 25-40 years if the roof is properly maintained. Guarantees focus on materials and installation, not wear from weather or blocked drains