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Radiant Floor heating questions...


alkeeney's Avatar
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07-31-10, 12:47 PM   #1  
Radiant Floor heating questions...

Doing some research on possibly putting in a radiant floor heat system. The house was built in the 1930's, one story with a basement, hard wood floor throughout with no subfloor and no other floor coverings.

First thought was to hang pex under the wood floors, but now I'm wondering if instead I should install a poured concrete system on the basement floor - using that thermal mass to assist with heating. Would that provide enough heat to rise up and heat the living space on the main floor?

Also, has anyone tried using the existing hot water heater in a radiant system?

I'm in central Indiana.

 
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airman.1994's Avatar
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07-31-10, 03:02 PM   #2  
First nothing green about radiant floor heat it is a comfort purchase. Your basement floor would not have been insulated so putting the heat tubing on top would cost you a fortune. Also you need the piping on the floor that you need the heat,

 
alkeeney's Avatar
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08-01-10, 09:04 AM   #3  
Posted By: airman.1994 First nothing green about radiant floor heat it is a comfort purchase. Your basement floor would not have been insulated so putting the heat tubing on top would cost you a fortune. Also you need the piping on the floor that you need the heat,
Thanks for the info on the basement floor.... I disagree about your statement that this isn't "green" though... attempting to eliminate or at the very least reducing the use of the existing forced air propane furnace to keep the house 'comfortable' sounds pretty green to me......

again, thanks for your input...

 
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08-01-10, 04:22 PM   #4  
You will still be using gas to heat the water that is heating the pipes. Then u will still have motor running for the pump.

 
Perry525's Avatar
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08-12-10, 07:31 AM   #5  
Pex radiates through 360 degrees, heat goes down as well as up.
To make this work you need a concrete pad about 4 inches thick.
To save on loosing half the heat you input, you need at least six inches of polystyrene/blueboard of similar under the concrete pad to stop trying to heat the whole state and another 2 or more inches round the edge to stop loosing heat into the walls.

One thing about under floor heating is, it is so nice to have, you never feel cold again and you are never too hot.
However, a concrete slab does take time to heat up and even longer to cool down. So when in the spring you get a sudden hot day, you have to open the windows to loose the heat.

While ufh is very good it cannot defy the laws of nature, to keep your existing set up as warm as it is, it will take the same amount of heat.

To save on heat input, you need to insulate and fill all the holes and cracks in your home.

Once you have sorted the insulation, yes you will be able to heat your entire home from that slab.......but, remember it will then at times be too hot.

Yes your existing water heater, fitted with a suitable circulator/pump will work, but remember what I wrote earlier, you will still need the same amount of heat input to heat the entire home as now.

Does it have enough output?

 
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