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3 Layers of Membrane

    Performance Layer, Scrim, Bottom Layer

    If you are familiar with single-ply roofing systems, then you’ve likely heard the different thickness such as 40 mil, 50 mil, 60 mil etc.  Duro-Last wanted to take a closer look into the thickness of these membranes and how they are constructed from manufacturer to manufacturer.

    As shown in the image above, there are 3 layers to a typical single-ply roof system. The top layer is called the “Performance Layer” because its what takes the beating from the sun, foot traffic, third party damage.

    Duro-Last examined 12 other membranes to note how thick their performance layer was, in comparison with Duro-Last 50 mil membrane.

    Not even the 60 mil membranes from our competitors were able to surpass the 28-mil top layer of the Duro-Last membrane. That’s interesting right? The top layer is the first line of defense, but the other manufacturers choose to build their layer with the bulk of their thickness below the scrim.  We cannot say for sure why, but the ASTM 4434 only requires 16 mil above the scrim. Duro-Last far surpasses this minimum requirement to provide thickness where it truly counts.

    Before you choose the roof system based on the thickness, be sure you know the makeup of the roof membrane.  It may not be what it seems. 

    We’d be happy to speak with you at length about these differences, give us a call. (740) 323-3174