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Barrier on floor

Techman Member Posts: 2,144
Is there such a thing as "the newest and best" barrier to go on top of a plywood floor , but under the mud , for a uponor radiant pex system? Thanks!


  • SWEI
    SWEI Member Posts: 7,356
    what's under the plywood?

    A suitable sheet of PE could well be all you need.
  • Techman
    Techman Member Posts: 2,144

    Hi SWEI ,there is nothing under the plywood at this time. Would the barrier on top protect the pex from the ply?
  • SWEI
    SWEI Member Posts: 7,356
    barrier on top

    will keep water out of the plywood during cure, and if anything spills later (assuming the crete is permeable.)  My point was really about temperature on the other side of the plywood and any insulation layer(s.)
  • psb75
    psb75 Member Posts: 811

    A masonry bond directly to plywood is not recommended. Especially one that changes significantly, thermally. You might consider several products made by this German company. They make excellent products for improving the bond between plywood sub-floors and masonry or ceramic finished floors. These products add some minimal thickness to the final floor. Not sure how they interface with pex, i.e. fastening pex down through the membrane.
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