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

https://telegra.ph/Incompatible-Adhesives-on-Single-Ply-Roofs---What-Happens-07-31

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