Single ply roof guarantees usually cover 15-20 years, but the actual roofing...

https://telegra.ph/If-I-Only-Do-One-Thing-This-Year-What-Roof-Maintenance-Is-Most-Important-07-31

Single ply roof guarantees usually cover 15-20 years, but the actual roofing can last 25-40 years with proper care. Guarantees focus on material defects, not wear and tear or maintenance issues