Does anyone out there have experience using radiant in floor electric heat. I’ve seen several systems advertised ( ie Step Warmfloor, Danfoss LX) and they seem very user friendly. I would be using it over a plywood subfloor and I’m curious how energy efficient they really are. Any input would be greatly appreciated, Dweezil.
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Electric heat can be 100% efficient, but not always PRACTICAL.
Most electrical in floor heating systems are only used as suplimental heat. That is they are used to take the chill off the floor. Most typically used in bathrooms.
But their are higher wattage systems that can be primary heat.
What is the finish flooring material?
Is their insulation UNDER the underlayment so that the heat is used to heat the floor and not the ground/basement/crawlspace or whatever under the floor.
And what is your cost of electricity.
William the Geezer, the sequel to Billy the Kid - Shoe
Bill, thanks for your response. This is a new home being constructed with an I.C.F. stem wall and SIPS walls. The subfloor will have R-19 insulation and tile floors. We are at 7200' elevation here in New Mexico with cold winters so forced air heat has proven to be impractical. In floor hydronic heat works well but involves a lot more components than the electric systems. We are part of an electric co-op so our cost is .068 per kwh, for now. Thanks again for your response, I look forward to more input. Dweezil
There are 3 things that need to be looked out.The cost of the source of energy.The method that it is delivered.And the capital cost of the different systems.And those are really separate. For example hydronic radiant heating deliver systems the water can be heated by solar, electric, heat pump, gas, oil, wood, and combinations.For delivery the 2 most common are forced air and infloor radiant. At that those rate electric heat is close, but probably won't beat out NG for the cost of energy. But that might not even be available to you. And it will probably beat out of sources. But with an apparently will insulated house then cost of energy won't be a significant cost.And with the floor insulation and tile finish you are a good setup for radiant of any type.You just need to make sure that you have a system that will deliver enough energy. As I said many of the systems are small and only for warming floor and not primary heat. But there are others that are for primary heat.So personal experience, but it sounds like it should be practical for you..
William the Geezer, the sequel to Billy the Kid - Shoe
There are different types of electric radiant heating panels:
Constant wattage systems, including cables on a spool, cables in mat or netting, wire mesh, and thin-films.
PTC self-regulating systems in a cable or flat heater.
Although most systems are line voltage, you also have some low-voltage products.
Most of the manufacturers of these products have a website with information on the different applications and installation procedures available. Make sure you specify your heating requirements, e.g., total heating, additional heat and/or floor warming. Your subfloor and finish flooring are also important. Some restrictions may able for some of the heating panels.
Some companies offer heat loss calculations and can give you the consumption for your specific application. For this you will have to give them, location, type of building and insulation values.
Remember that thermal insulation under the heating panels is important.
Besides the manufacturers' website, you can go to the the Radiant Panel Association (http://www.radiantpanelassociation.org) or e-mail the RPA Electric Committee ([email protected]).
I have two bathrooms in my home that have electric radiant heat. To me and my family they are the best things since sliced bread. My bathrooms are about 20 squire feet. I used Warmly Yours. There Website is great and very user friendly. The programmable T-stat is great. Turns it on in the morning and the evening. I installed the heating mats on 3/4 inch ply and then covered them with 1/2 inch SLC, then tile. I pushed the temp up a bit so I can use them as primary heat. I would not do a tile floor with out a heating mat.
We've installed them on several jobs. It makes the tile floor more difficult to install, and you have to be very careful not to cut the element. Installing a continuity meter on the circuit during the tile job could save you a major hassle.
Like Bill said, not for primary heat, but great for taking the edge off a cold floor. If they're not on all day they won't cost much to run. They are expensive up front though.
I have electric heat mats installed under all the tile floors in my house. Two different versions from two different manufacturers. Two type of controllers.
One is a cable type, held down with clips, from InFloor. I put it over Durock, covered it with thinset and tiled over it. This type costs less than the matt type. IF you use the cable type, I would recommend covering it with a self-leveling floor compound. This will add 1/4 to 3/8" to the floor height. The controller has a thumbwheel for temperature adjustment and works off of room air temperature, with an internally set floor temperature high limit.
The second type I have installed in my house is a matt from NuHeat. This type is set in a thinlayer of thinset and tiled over. Adds 1/8 to 1/4 to the floor height. The controller is a digital, programmable type and controls the floor temperature only. This type costs more but installation is easier and the controls are programmable.
Both types and controllers have their good and bad points. In interior or well insulated space, these systems will provide all of the heat you need in all but the most severe climates. They typically require dedicated circuits. You can run multiple matts off of a single controller, depending on the wattage. All of mine are 120 volt, but 240 volt version are available from most manufacturers.
I like the air temp controlled unit in my master bath, because at night when the furnace is on setback, the floor heat keeps the tile floor toasty. Ever walk on a cold tile floor in the middle of the night in winter, barefoot? That alone is enough to install these (in a house that is not RFH already) units.