Single ply roof guarantees usually cover 15-20 years, but these roofs often...

https://knoxuqsk688.cavandoragh.org/do-certified-installers-really-make-a-roof-last-longer

Single ply roof guarantees usually cover 15-20 years, but these roofs often last 25-40 years if maintained properly. The guarantee focuses on materials and installation, not wear and tear over time