Question

We are considering radiant heated floors for our bermed home. The initial cost is very large. Is it worth it?

Asked by Shirley
Burns, KS

ICF on exposed walls. One level, 2200 square feet home. Rafted roof. Suggestions?

Answer

Sean Lintow Sr

Answered by Sean Lintow Sr

Naperville, IL

SLS Construction & Building Solutions

March 6, 2013

Shirley,

I am not sure what you consider a high initial cost and in all reality the only one that can answer the "is it worth it" question is you.

With that I would recommend that if you are still undecided, now would be the time to install the PEX piping in case you decide you want to try it later. Just make sure while they are pouring that the system is pressurized with a gauge left on it so any accidental punctures can be dealt with now.

Pluses of radiant heating

I am sure you know about many of the pros:

  • it is an efficient means of heating a space,
  • there is no air movement resulting in reduced dusting & increased IAQ,
  • the ever popular warm toes,
  • along with having very few components that can fail.

As for costs, one of the biggest things I would mention is that you are apparently building a very tight and highly efficient house. What this means is that:

  • you don't need a huge boiler, but
  • instead you can probably just use a tankless water heater or a water heater.

All this leaves you needing is the pex lines, a mixing valve, and a pump. I am not adding the foam under the slab as part of the initial cost as that is already required by code.

Minuses of radiant heating

On the con side, many in the home performance world are worried about "over-heating" and it not being as efficient as claimed, etc.

The efficiency depends a lot on the getting the system designed properly from the start and how you use it. Please remember that unlike forced air system, this system relies on radiating the heat from the floor so turning it off or using lower set points during the night is not only not a good idea but will take longer for the spaces to heat up.

As for the overheating - this gets back to the proper design, sizing & using a lower set point for the water entering the system.

 

For more information:

I would recommend you read my radiant heating FAQ and find a qualified and knowledgeable individual in your area that will do an accurate Manual J & layout for you.

Also, read "Is hydronic radiant flooring better than electric in terms of cost, heat generated, and installation ease?" a Q&A answered by Randy Potter.

Tagged In: heating cooling

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