Single ply roof guarantees, usually 15-20 years, cover specific materials and...

https://rapid-wiki.win/index.php/Ponding_Water_at_Upstands:_Design_Problem_or_Maintenance_Issue%3F

Single ply roof guarantees, usually 15-20 years, cover specific materials and workmanship under set conditions, but real service life often extends to 25-40 years with proper care