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Hydronic floor in slab under fire stove

MichaelQC Member Posts: 1
edited October 2023 in Radiant Heating
Hello everyone,

I am installing a hydronic floor in my slab, I will have a smallish fire stove I will use occasionally that will be standing on 12 inch legs. It's a cast iron high efficiency 46000btu smallish stove.

Probably will install a granite/mortar hearth for the fire stove area 4" high, if not I will definitely install some sort of  flooring to protect concrete from cracking (porcelain tile with something underneath). Do you see any issue with me installing the PEX A pipe in the slab under the fire stove? 

I think it should be fine, but I am afraid the heat of the stove will radiate and bring the slab and the PEX pipes temp above its spec.

I guess having the granite base is not an issue in itself ( will just limit and slow the radiant heat from the hydronic)


  • Intplm.
    Intplm. Member Posts: 1,992
    As a precaution, I would avoid the radiant close to that much of a heat source.....the wood stove.
    Similarly, when installing radiant in a floor near a wax ring on a toilet I usually keep the radiant floor heat away from the wax ring too.
  • hot_rod
    hot_rod Member Posts: 22,244
    A simple heat shield made from a piece of aluminum or stainless sheet metal will make a big difference below the heater.
    That is how double and triple wall flue pipe is built. A small air space to keep the outer pipe from over heating. Some stove manufacturers offer “heat shields” for under or behind wood stoves.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Dave Carpentier
    Dave Carpentier Member Posts: 594
    I agree some kind of shield in/on a raised platform would ensure.
    Maybe worth burying a couple of thermal sensors near the pex ? That way you could monitor for a year or so just for peace of mind.
    30+ yrs in telecom outside plant.
    Currently in building maintenance.