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Hot & Cold in the slab

I know O-barrier radiant piping is designed to go in concrete, but I have an island that needs hot and cold pex to the sink that will be buried in the concrete. Do I need a special type or encase the pipe in something else?


    JUGHNE Member Posts: 11,021
    Often it is wise to install two 2" PVC conduits with the standard sweeps from under the island to somewhere above the concrete. Be it inside a wall, crawl space or basement.

    Good for future replacement if needed or perhaps filtered water line. 2 pipes will insulate the hot and cold from each other.

    Cheap insurance at this time. IMO
  • GroundUp
    GroundUp Member Posts: 1,865
    The O2 barrier is to protect the internals of the heating system from O2, nothing to do with the concrete. You would use regular non-barrier tubing for domestic hot and cold to the sink, but as was mentioned I would put a sleeve of some sort in the concrete should the tubing need to be replaced or manipulated some day
  • hot_rod
    hot_rod Member Posts: 21,835
    You can buy pre-sleeved pex, or buy the sleeve material separate.

    1/2 pex should easily fit inside 1" PVC. Make a nice curve to PVC by warming with a heat gun, or very carefully with a torch.

    Electricians have PVC heaters to make bends and offsets in PVC.

    Hopefully it is a short run, if not insulation would help speed HW delivery.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream