Retrofit underfloor radiant heating?

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LarryG

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I am in the middle of 2 bathroom remodels. One has already had the wet-bed and tile installed on the floor. Is there a way to safely and efficiently install underfloor radiant heating? The rooms are on the second floor and the ceiling below have been removed to expose the underside of the subfloor. The subfloor is 1x4 tongue and groove. There is about 1 1/2" to 2" of wet-bed and pebble tile. My concerns; will heat radiate up through the wood subfloor, and will the heat damage the floor joists or subfloor? If this can work any suggestions for manufacturers or brands?

I do not have hot water heat in the house and would hope to use an "electric tape" type heat source.
 
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Jadnashua

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Hindsite is expensive! Do you have a boiler? You have a lot of mass to heat up. Electric would have worked in the floor sandwich (i.e., under the tile), but I don't think anyone would recommend it as a staple up. Hydronic staple up would work, but your supply temperature will need to be much higher (and thus less efficient) plus, you'd need plate diffusers to spread the heat more evenly. Response rates will be very slow. Either would have been much more efficient and easier to install as part of the mud bed underneath the tile.
 

hj

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heat

Wood is a very poor heat transfer medium, so you need a lot of temperature to penetrate it, then you also have to heat the subfloor and tile. Most electric panels have a very small BTU factor so they would probably have to work almost 24/7 to keep the floor warm.
 

Scuba_Dave

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They do make them, I looked into them for our kitchen
Basically they come in rolls that fit between the joists
You'd need to most likely push rigid insulation up under them to trap the heat & heat the floors & not the air
I never looked into it too much, decided against it as the kitchen has a large radiator

http://www.suntouch.com/underfloor/

After connecting your SunStat thermostat and testing the system, install R-11 to R-19 fiberglass batt insulation up to the mats. Also install insulation vertically at the ends of the joist bays or 6 inches after the mat ends.
 

Jar546

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Don't waste your money, time or effort on an electric system in this particular case. You need a hydronic system.
 

mulveykemster

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LarryG

The newly constructed houses are now coming with the new Underfloor heating system. Underfloor heating systems require a wooden or tiled flooring to be effective and to work efficiently. The feel of suntouch com with underfloor heating makes you feel better. Hope you need this..
 
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