Single ply roof guarantees of 15-20 years cover material and workmanship, but...

https://wiki-saloon.win/index.php/If_I_Only_Do_One_Thing_This_Year,_What_Roof_Maintenance_Is_Most_Important%3F

Single ply roof guarantees of 15-20 years cover material and workmanship, but the actual service life can be 25-40 years with proper care. Factors like weather, maintenance, and installation quality all play a role