I know this thread is from more than a month ago. I would say this roofing system is either Fibertite or Dura-Last. PVC membranes have been known for lasting 40 years plus but alot has to do with the manufacturing process, quality of polymers and the ammount of fillers. I am a Technical Sales Representative for Sarnafil a Division of Sika. We manufacture PVC roofing, water proofing membranes (for plaza decks, green roofs and tunnels) as well as solar integrated PVC membrane. If you have any further questions please don't hesitate to contact me or visit our website. www.sarnafilus.com schmidt.justin@us.sika.com Thanks, Justin