Single-ply roof guarantees typically cover 15-20 years, but a roof’s real...

https://www.bookmarkidea.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 a roof’s real service life can stretch to 25-40 years with proper care. The guarantee mainly covers materials and workmanship, not wear and tear or maintenance issues