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

https://www.pop-bookmarks.win/single-ply-roof-guarantees-often-cover-15-20-years-but-the-actual-service-life

Single ply roof guarantees typically cover 15-20 years, but the actual service life can stretch up to 25-40 years if the roof is properly maintained. Guarantees focus on materials and installation, not wear from weather or blocked drains