Radiant Floor Heating Efficiency
I have a brand new home in Northern Virginia. The home has a 9′ high full in-ground basement that is currently unfinished. I am wondering when we decide to finish this in the coming years what is the most efficient way to do so.
In my experience the basement tends to be cooler or cold and damp. We should have adequate drainage through the drain tile system, sump pump, and foundation water proofing.
My main question is regarding the efficiency of radiant floor heating. Because the slab is already poured I would assume that this would need to be an electrical radiant system. Is there any way to retro fit a hydronic system on top of a finished slab at all? Is it more efficient to heat the basement with the radiant system then the forced air? I know that the concrete floor has thermal mass that should hold some of this heat in, but if I didn’t want to do ceramic tile flooring what material would be best on top of this (keeping in mind that this would be a family room type setting).
If the basement is heated using the radiant floor (if this is possible), would it be best to cut this “zone” off from the natural gas heated part of the house?
Any advice for radiant floor heating and/or finishing a basement will be greatly apprecaited!
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Replies
Shaun,
Q. "Is there any way to retrofit a hydronic system on top of a finished slab at all?"
A. Yes. You need to have insulation under the hydronic tubing. If you know that the slab has an adequate layer of foam insulation under it, you can install tubing on top of the existing slab and pour a new slab on top of the tubing. You could also install sleepers and one of the Warmboard-type products. If there is no foam insulation under the slab, you need to install foam insulation on top of the existing slab before proceeding with the steps listed above.
Q. "Is it more efficient to heat the basement with the radiant system then the forced air?"
A. No.
Q. "If I didn't want to do ceramic tile flooring what material would be best on top of this (keeping in mind that this would be a family room type setting)?"
A. A wide variety of flooring types can be installed on top of a floor with radiant heat, ranging from laminate to hardwood, although I think that ceramic tile makes the most sense in a basement.
Q. "If the basement is heated using the radiant floor (if this is possible), would it be best to cut this zone off from the natural gas heated part of the house?"
A. First of all, natural gas can be used to heat water that circulates through hydronic tubing, so you can use natural gas as a fuel for your whole house if you want. You can install hydronic tubing in your basement as a separate zone if you want; it's also possible to have your entire house on a single zone if you prefer.