No garage floor insulation: What are the consequences?
Let me be up front and say that I know I made the mistake, but I’m looking for possible solutions: I built a home and installed PEX tubing in the garage slab with the intention of having a radiant floor heating system. The slab is now poured and I DID NOT INSULATE under the slab.
While I know this is undisirable, I want to know if it is so bad that I should not continue with the radiant system. I could switch to gas heat for about the same cost as the remaining components for the radiant system, but i would still prefer the heated slab. I live in North Dakota, near the Canadian border, so it is very cold during the winter months.
Will it be more costly to get enough heat into the garage to have it warm than to run gas? Will it even get to temperature with no insulation under the garage?
Thanks,
Dane
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Replies
Dane,
Big mistake. I wouldn't use the tubing to heat your garage.
If you ever want to heat the garage, you should install rigid foam on top of your existing slab, and then pour a new concrete slab on top of the foam. Abandon the PEX tubing.
Some people will probably advise you to salvage a partial solution to your current disaster by installing some vertical rigid foam around the perimeter of your slab. That's really not good enough, however -- not in North Dakota. You live in a worst-case climate, Dane.