Single ply roof guarantees, usually 15-20 years, cover workmanship and...

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

Single ply roof guarantees, usually 15-20 years, cover workmanship and materials but aren't the full story. These roofs often last 25-40 years if properly maintained. To get the most from your roof, arrange annual inspections and clear drains regularly