DIY Dude - DIY Electric Radiant Floor Heating Tutorial - Make you own radiant floor heating!

DIY Electric Radiant Floor Heating Tutorial - Do it yourself and save!

After searching the internet for various DIY electric radiant floor heating tutorials, I found out there was not much information out there for the true do it yourselfer ( DIY ). So, I spent many hours researching the various manufacturers of radiant floor heating systems to learn about the needed radiant floor heat components. I used the information I found to compile a list of needed materials, and then set out to find suppliers for these materials. My goal was to gather the materials, and install my own electric radiant floor heating system myself, while saving a notable amount of money. However, I was not willing to sacrifice performance in order to save money. In fact, I wanted better performance, for less money. Here's how I did it!

	First, I sourced out a manufacturer of heating wire. Heating wire is the heart of an electric radiant floor heating system. Heating wire operates on standard household electricty, which is 120 volts AC. There are a few heating wire manufacturers out there. The I contacted claims that they manufacture the wire that is used in the floor heating systems sold at Lowe's and Home Depot. Since I had already looked at those systems, I knew they were more expensive than what I wanted to spend. I purchased enough heating wire to cover 45 square feet of floor space. The bath room I want to install this heating wire in is about 90 square feet of flooring, so I would be able to get some good coverage with this wire. I got enough heating wire to cover 45 square feet of flooring for $120 shipped. Compare that to $424.99 for a 45 square foot preassembled kit!
Up next, I needed to locate a line voltage thermostat, which would be needed to control the temperature of my electric radiant floor heating system. I looked at what thermostat controls the big brands were offering and noticed that they all pretty much looked the same. What I figured out was most of the indepent manufacturers of floor heating systems were using a line level thermostat that was made by the same manufacturer! So, I contacted Honeywell to see if they would sell me a line voltage thermostat that would allow me to program my floor heating system. No luck! Since I don't operate as an electrical supply contractor they would not sell me the thermostat. Next stop...eBAY! I was able to purchase an Honeywell line level programmable thermostat for $100 less than what Home Depot sells it for! Wow!
	Now for the tricky part. These pre-packaged radiant floor heating kits come with the heating wire attached to a really nice fiberglass mat system, and all you have to do is roll it out on the floor before you put your hard flooring in. My homemade electric radiant floor heating system doesn't have that nifty little fiberglass mat. What to do? Well, when I was speaking with the engineer over at the heating wire manufacturer, I asked him the various ways I could attach the heating wire to the subfloor before installing my ceramic tile. He explained to me that all I needed to do was keep the wire in place long enough to install the tile and then the mortar would hold the wire in place indefinitely. He said "you could even use duct tape if you want!" Guess what I used to hold my heating wire in place...you guessed it! Duct tape!
The inital install went quite well, considering the crudeness of the fastening materials. I found it easy to hold the wire into place and affix it to my Durarock subflooring with some cheap duct tape. I found some cheap stuff that seemed super sticky, so that's what I used. The hardest part was cutting the tape and holding the wire in place, so I had a partner help by cutting tape while I fastened the heating wire to the floor with the tape. I spaced the wire as the floor heating wire manufacturer suggested, which is at 2.75" spacing intervals. This gives me a safe power output of 12 watts per square foot of heated floor space. The maximum output by National Electric Code is 15 watts per square foot, so you could, in theory, space the floor heating wires a little closer to get a higher heat ouput, and, in turn, a warmer floor. Since I live in the South, and we bottom out at around 25 degrees farenheit , I think 12 watts per square foot will do just fine.
	I took me a little over an hour to install my floor heating wire. I should mention that I spent an additional 30 minutes, or so, thinking about where I wanted my floor heating, and marking the floor to assist in placing the heating wire. In hind sight, turns out my method is probably easier than using a store bought electric radiant floor heating kit, at least for my application. The fiberglass mats seem to limit the installation to straight runs. Of course, you can cut the mat and reposition to turn corners, but, be careful! You just paid a lot of money for that floor heating wire and you don't want to cut it!
So, in all I have about $200 in my DIY electric radiant floor heating system. Not bad! I'll be placing the ceramic tiles in the next couple of days, so stay tuned to for Part 2. I will also install the line level thermostat so you can see how that works. Come back soon! Jon - The DIY Dude