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Rob Blaustein
10-04-2005, 12:43 PM
We're putting in a new master bedroom and bath (tile floor in the bathroom) and would like to install some sort of radiant floor heating for the bathroom. Since our house uses forced hot air we thought we'd use an electric system (but if that logic is faulty, let me know). Does anyone have any experience with these and can you recommend (or warn us against) a particular brand--there appear to be many out there. I did see an interesting product used on a remodel on the DIY network--it was a conducting polymer that heated up, and it was also I think the only low voltage version of electrical radiant heating. The company was called Step Warmfloor. Anyone have any personal experience with them? Thanks.

Ed Breen
10-04-2005, 5:22 PM
Rob,

I'm no expert, but if you are still in the design phase why not use the hot water system for your home to provide the heat. If you are putting in an "always hot" system, you can tap into the line on the return side and keeep your floor toasty. Use of a by pass for summer use would be wise.
Just my thoughts!
Ed:rolleyes:

Rob Russell
10-04-2005, 5:37 PM
Rob,

What you use depends on what you want to do - heat the room with the radiant heat or have warm floors for your tootsies on those winter days we get in New England.

If your desire is to heat the room with the floor, you really want a hydronic system. You could do a small system just for the room with a mini hot water heater as the heat source. The bathroom would have its own thermostat, so you could have the bathroom warm and bedroom cool as many of us up here like to do.

The low voltage system you referred to is good for taking the chill off of the floor so you can walk on it barefoot, but not as a primary heat source.

My experience is based on the research I did as part of the design for a 1000 sq ft addition to our house, 768 sq ft of which has hydronic radiant heat that I installed.

We're looking at redoing our upstairs bathroom and I'd consider adding the LV heat under the tile for tootsie-comfort purposes, but certainly not as a heat source.

Rob

Frank Hagan
10-05-2005, 1:48 AM
We're putting in a new master bedroom and bath (tile floor in the bathroom) and would like to install some sort of radiant floor heating for the bathroom. Since our house uses forced hot air we thought we'd use an electric system (but if that logic is faulty, let me know).

The logic is probably sound. You would have to buy a boiler to use hydronic heat, so the initial installed cost would be much higher ($2500 plus, probably). But generally speaking, the hydronic heat would be less expensive over the long haul (although oil and gas are getting to be more and more expensive ... electricity is still a higher cost fuel). The payback for an auxillary "toasty feet feel good" floor could stretch out over a decade with the hydronic option. Can the existing forced air system handle the extra square footage or do you have to upgrade it?

Ditto on the difference between 24v and the higher voltage electric radiant floors. I would go with the 120v version. It will make the tile feel warmer (tile and carpet in a room can be the same temperature, but the tile may feel much colder because it "conducts heat" away from you while the carpet doesn't). Being able to boost the temp of the floor for those cold mornings can increase comfort.

Bill Lewis
10-05-2005, 7:27 AM
We installed an electric floor warmer in our master bath. I can't recall the brand name, but could find out for you ("Warm Floors", I think). We have been very happy with it. It does take the chill off of the floor, and definately makes it more comfortable.

We installed a timer controller at the suggestion of the electrician and electrical supplier. There was basically no cost difference to us, but I'm not sure it was worth it. The timer is not intuitive, and since it takes awhile to heat it up it's hard to set it up for the right times. Last winter I just turned it on and left it. I may try again this winter to set times.

Ours is a 120V system, but there was also a 240V system available. If we were to do it again, I think I would opt for the 240V system. I think it might warm up quicker.

It does warm the room a bit, but I doubt you would want to make it the primary sourse of heat. Keep your forced hot air and A/C.

Would I ever do it again? Absolutely! We both feel that it is one upgrade that we really enjoy.

Any other questions, just ask here or PM me.

Rob Blaustein
10-05-2005, 12:18 PM
Thanks for all the helpful feedback. Although my contractor hasn't had his HVAC guy over yet, my sense is that the bathroom would be heated (and cooled) using our existing forced hot air (and central air). The radiant heating would only serve to warm up the tile for our "tootsies", since as Frank points out, the tile will feel cold even if the room is a comfy temp. I gather this is mostly due to the nature of forced hot air vs other heating systems--the walls and floors take much longer to warm up. We keep the house thermostat on a timer and set it to turn up the heat shortly before we wake up so the air is warm but the floor is still chilly.

Dave Richards
10-05-2005, 3:47 PM
Rob, in Norway it is common for bathroom floors to be heated. In most of the hotels we stayed in while visiting there a few years ago, there was no bathmat but there was no need for one either. What a civilized thing to do, installing a heated bathroom floor. On thing I also noticed that seemed to be common was to make have the shower as just a corner in the bathroom so the floor of the shower is warm, too

Boyd Gathwright
10-06-2005, 12:34 AM
Hi Rob,

.... My experience with radiant heat is very old. I do know if you go to bed with the heat turned down or off and it is cold when you wake up in the morning, it takes a LONG time for it to come up to temperature. Other than that it's great.

.... Sorry I could not offer you any other pointers, good luck :).

Boyd



We're putting in a new master bedroom and bath (tile floor in the bathroom) and would like to install some sort of radiant floor heating for the bathroom. Since our house uses forced hot air we thought we'd use an electric system (but if that logic is faulty, let me know). Does anyone have any experience with these and can you recommend (or warn us against) a particular brand--there appear to be many out there. I did see an interesting product used on a remodel on the DIY network--it was a conducting polymer that heated up, and it was also I think the only low voltage version of electrical radiant heating. The company was called Step Warmfloor. Anyone have any personal experience with them? Thanks.

Frank Hagan
10-06-2005, 2:13 AM
Thanks for all the helpful feedback. Although my contractor hasn't had his HVAC guy over yet, my sense is that the bathroom would be heated (and cooled) using our existing forced hot air (and central air). The radiant heating would only serve to warm up the tile for our "tootsies", since as Frank points out, the tile will feel cold even if the room is a comfy temp. I gather this is mostly due to the nature of forced hot air vs other heating systems--the walls and floors take much longer to warm up. We keep the house thermostat on a timer and set it to turn up the heat shortly before we wake up so the air is warm but the floor is still chilly.

I think tile feels cold even with other forms of radiant heat (baseboard, electric elements, etc.) In-floor radiant heat warms the floor above the air temp so you don't get the cold feeling. Tile conducts heat away from the body faster than wood or carpet, so it feels colder.

Norman Hitt
10-06-2005, 3:22 PM
I think tile feels cold even with other forms of radiant heat (baseboard, electric elements, etc.) In-floor radiant heat warms the floor above the air temp so you don't get the cold feeling. Tile conducts heat away from the body faster than wood or carpet, so it feels colder.

When we bought our current house some 29 years ago, it had carpet in all three bathrooms, and neither of us was sure we would like it, but figured we would give it a try, and could always put in tile when we made the next carpet change. Well, it didn't take long for both of us to really get to like the carpet, it's never cold on the feet and doesn't require any extra heating costs, looks nice, never slippery, (which is important as we get older) ;) , and neither of us would even consider going back to tile, (one of the Very FEW things we have both ever agreed on), :D but that's just us, I guess. :D We do keep a small rubber backed throw rug in front of the shower door to keep the carpet dry as you step out of the shower and it works great.

These days, I especially like the "No Additional Heating Costs for the Floor", and I never could understand the shower floor heating I saw in Europe, as this seems like a waste of energy costs to me, since I always turn on the water and regulate the temp Before I get in, and the floor is always warm by the time I step in there. Different Strokes for Different Folks, I guess. :)

Hope you find a good economical but effective solution to the problem.

Bjorn Andersen
01-25-2007, 9:44 AM
Rob, in Norway it is common for bathroom floors to be heated. In most of the hotels we stayed in while visiting there a few years ago, there was no bathmat but there was no need for one either. What a civilized thing to do, installing a heated bathroom floor. On thing I also noticed that seemed to be common was to make have the shower as just a corner in the bathroom so the floor of the shower is warm, too

Living in Norway, I can certainly vouch for that, Dave. We've got very strict rules tho, on who can install any and all kind of heating in floors; and especially in bathroom floors. We now use a lot of heated water in pipes in the bathroom floors now, both from boilers and from heat pumps (much like AC's, but with hot air instead of cool air) to heat up the water running in the pipes in the floor. When one builds a new house its almost mandatory to heat all the floors in the house in either by heat pumps or boilers, or from ground water.

Low voltage heat is usually restricted kitchens and low traffic rooms, as this heat is just for comfort and not for heating per say. In for instance in a hall you'll need "real" floor heating for drying up water from wet and snowy boots.

Oups... got a tendency to get carried away. Sorry 'bout that! :p

Chris Padilla
01-25-2007, 10:08 AM
Timely thread. We are at the beginning stages of adding about 140 ft^2 to our master bedroom on the 2nd floor. I wondered about putting in some kind of floor warming (not room heating) system. Yes, we still get cold mornings here in California---uh, according to my wife! :)

What she would really like is a nice "bench" in the shower that is warm for her to sit on. I was thinking to simply "weave" some extra hot water copper pipe through the tiled bench area but I don't think it would get warm enough without the shower running for a while.

What are some good ideas to warm up a shower seat? Could this floor warming electric system work for the shower seat? Thoughts?

Rob Russell
01-25-2007, 10:43 AM
Timely thread. We are at the beginning stages of adding about 140 ft^2 to our master bedroom on the 2nd floor. I wondered about putting in some kind of floor warming (not room heating) system. Yes, we still get cold mornings here in California---uh, according to my wife! :)

What she would really like is a nice "bench" in the shower that is warm for her to sit on. I was thinking to simply "weave" some extra hot water copper pipe through the tiled bench area but I don't think it would get warm enough without the shower running for a while.

What are some good ideas to warm up a shower seat? Could this floor warming electric system work for the shower seat? Thoughts?

Chris,

You don't want to use the regular hot water feed to heat the bench seat - it'll pull a lot of heat from your shower water.

For something like what you want, I'd install a small, closed radiant system. Consider using one of the tankless hot water heaters. The big thing would be whether you can feed warm/hot water into one of the tankless heaters. Assuming that you can feed heated water into the tankless heaters, this way you'd have a small system, small circulator pump, and could put it on a combination timer and thermostat. Walk into the bathroom and turn the timer on. The circ pump starts, the tankless heater starts heating the water up and your bench starts wrming up. When the bench gets warm, the thermostart would kill things so you don't overheat the seat. You could also run the hot water through a towl rack so - on those chilly mornings when your wife wants the shower seat warmed up - she has a hot towel when she goes to dry off.

Rob

Chris Padilla
01-25-2007, 3:07 PM
http://www.warmfloor.com/english/

I just found this site that Rob alluded to. Looks pretty cool. I'm definately going to dig into it.

I'm putting down about 450 ft^2 of wood floors (maple, 5" plank, engineered, prefinished) in our main living room. This room is always cold in the winter and so I tore out all the drywall on the exterior walls and am upgrading the insulation from pink R-7 to R-13 (Johns Manville encapsulated roll--really like working with this brand, style).

Later, we'll get a new roof and I'll get that insulated (if it isn't) or upgraded (if it is insulated, which I don't think it is).

This Warm Floor stuff looks mighty, mighty interesting...especially since I have the studs exposed...makes wiring a snap NOW.

I think this system could work fine in the bathroom and to warm towels and a shower seat.

Chris Padilla
02-05-2007, 4:36 PM
I thought I'd update this thread.

I got a quote of $5600 to do my ~450 ft^2 living room...and it didn't een include tax or shipping! :eek:

I'd attached the quote they gave me but it is too big for the file sizes allowed here.

I dunno...seems awful spendy for one decently sized room. What do y'all think? PM me and I'd be happy to pass along my quote. I have two XLS spreadsheets (446 kB and 2 MB each) and one PDF at 230 KB.