Single ply roof guarantees usually cover 15-20 years, but that’s just the...

https://brooksfznx367.theburnward.com/how-can-i-tell-if-a-leak-is-workmanship-or-material-failure

Single ply roof guarantees usually cover 15-20 years, but that’s just the manufacturer’s promise under ideal conditions. In reality, a well-maintained roof can last 25-40 years