Single ply roof guarantees usually last 15-20 years, focusing on the product...

https://www.bookmark-belt.win/single-ply-roof-guarantees-usually-15-20-years-cover-product-defects-but

Single ply roof guarantees usually last 15-20 years, focusing on the product and installation quality at that time. However, the actual service life can stretch to 25-40 years with proper care