Single ply roofing guarantees often cover 15-20 years, but the real service...

https://super-wiki.win/index.php/How_Long_Does_a_Single_Ply_Membrane_Roof_Last_in_Real_Life%3F

Single ply roofing guarantees often cover 15-20 years, but the real service life can stretch to 25-40 years with proper care. The guarantee usually focuses on materials, not wear and tear or maintenance