Single ply roof guarantees usually cover 15-20 years, mainly focusing on...

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

Single ply roof guarantees usually cover 15-20 years, mainly focusing on material defects. But in reality, these roofs can last 25-40 years with proper care