Does anyone have experience with hydronic heating under subfloor and carpet? I am building an addition and plan to heat with hydronic tubing under 3/4 OSB subfloor with carpet over that. I know that doesn’t give me the benefit of mass like concrete but it seems like a better option than hot water baseboards. My heating contractor suggests creating an airspace around the tubing by spacing the insulation down from the floor 1-1/2″ thereby allowing the heat to move up through the floor. The exsisting house is in-slab radiant heat. Any thoughts or recommendations would be helpful.
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Haven't tried this yet but a HVAC contractor on my job says to use the subfloor that has the grooves cut for the PEX tubing with the aluminum baffles already installed, followed by a layer of Wonderboard (cement backer board) over it, then whatever flooring material you want...
Sounds like a good solution but I have yet to try it.
Re: in slab radiant heat. Is it bare copper tubing? If so, get the jack-hammer out.
Another co-worker just purchased a house with in slab bare copper tubing and surprise, surprise, it's leaking like a sieve....He's spending the next few weekends re-piping his house.