Single ply roof guarantees, usually 15-20 years, cover product defects but...
https://melissafreshmaid.com/tpo-vs-pvc-lifespan-what-matters-more-than-the-material/
Single ply roof guarantees, usually 15-20 years, cover product defects but don’t always reflect the roof’s full service life, which can reach 25-40 years with good care. To help your roof last longer, get annual inspections by an SPRA-approved contractor