Single ply roof guarantees typically cover 15-20 years, but the roof can...

https://www.bookmarkzoo.win/a-single-ply-roof-guarantee-usually-covers-15-20-years-but-the-actual-roof-can

Single ply roof guarantees typically cover 15-20 years, but the roof can actually last 25-40 years with proper care. The guarantee focuses on materials and workmanship, not long-term wear and tear