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Question about floor treatment.

nibs Member Posts: 500
2" thick radiant slab on R20 +/- insulation.
Am thinking that under the box bed, and possibly under kitchen cabinets, it would be a simple matter to place a sheet of XPS or equal on top of the floor, hidden under the furnishing so that the BTU's are encouraged to radiate into more useful places.
Also to correct what may have been a mistake on my part, I placed pex within a few inches of the two doors to counter cold air entry, am thinking that in cold weather (20 below), it might be a good idea to place a rug at the entry ways, to help keep the slab warmer. Entry ways both have excellent (ICF) edge insulation Trying to avoid anti freeze in the system.
Am also thinking of a rug in front of the often used fireplace, again to encourage BTU's to work more efficiently.
Finish floor will be ceramic tile, with few rugs etc. Work to recommence in about a month.
Thanks for your thoughts.


  • Gordy
    Gordy Member Posts: 9,537
    Rugs at entry ways are usually a given, a place to wipe feet. I doubt with even a run of the mill exterior door, and threshold it would freeze that loop. At -20 the system will be running more.

    Placing xps on top of the concrete under cabinets would make cabinet installation a pain. Plus you wouldn’t eliminate the conductive path of the concrete. I really think you get a nicer install if you run your loops a bit under the toe kick. While it doesn’t do much for the space heating, it does warm the toe kick area a little better standing there barefoot. Also looping under sink cabinets that are on an exterior wall is nice to help keep supply plumbing a little bit warmer.

    Maybe I’m not picturing what you are doing well enough. 2” slab on xps which is in a subgrade? Or existing slab?