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

https://trevorsinspiringnews.yousher.com/how-long-should-a-quality-membrane-roof-last-on-a-distribution-centre

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