Electric floor heat can turn bone-chilling tile or stone into a warm and welcoming experience. Think of what a difference it would make to step out of your shower on a cold winter morning onto a warm, heated floor. Generally, hydronic or water-based radiant heat, is used for heating the entire house while for discrete areas-such as a bathroom - electric radiant floor heat is best as part of your home heating system.
While electric floor heating was once the purview of high end homes only, recent changes have made the installation process easier and more accessible to the average homeowner. Heating elements are embedded in mesh mats that are generally 1/8 to 1/4 inch thick so that they retrofit into most homes without affecting floor height. There are many different brands of systems available so be sure to check the manufacturer's details and choose the type that is most compatible with your floor materials. Also buy a system with built-in ground fault protection and a high-limit temperature sensor. Although you'll want to use an electrician at the tail end of the process, you can minimize his time-and your money-by doing the rest of the installation yourself.
Don't be intimidated just because you will be working with electric wire. The heating element will come embedded in a roll of mesh wire. You order it to size and then cut the supporting mesh (without cutting the heating wire!) so as to be able to maneuver and fit it easily. As long as you do not slice, crush, or otherwise damage the electric wire, you will be fine. No splicing, no electrical connections, no expensive electrician!
Here's how to install electric floor heat on your own:
- Electric floor heat can be installed on concrete or cement backerboard, and plywood. Inspect your subfloor. Make sure that there is nothing sharp in or on it that could damage the heating wire. If you want to lay down installation beneath the wire mesh, now is the time to do so.
- Sometimes the mesh comes with the electric wire already in place and sometimes you need to snap it into position. Once the electric wire is in position in the mesh mat, lay the mesh down. Cut the mesh to fit-just be sure that it is the mesh that you cut and not the electric cable. Be sure that you maintain close to the same spacing between the heating elements in areas that you must custom fit. Never put the heating elements too close together as this could cause overheating. You may want to make the mesh even more secure by either gluing, taping, or stapling it-once again, staple the mesh and not the electric wire.
- Do not put heating element beneath fixtures such as the toilet or sink.
- Install your floor sensor. Ideally, you want to place it in an area with nothing above it that might trap the heat. The sensor is telling the system what temperature the floor is-if it is in a spot where heat gets trapped, the sensor will not be accurate. The sensor wire should not cross any heating element. Local electric code in your area may require that the low voltage sensor wire be placed in a separate conduit than the high voltage heating element wires behind the wall.
- Just as when you're putting up your Christmas lights, if there is a break anywhere in the line for electric heating systems, the rest of the lights won't work-the same goes for your electric floor heat. Invest in a continuity tester so that you can test as you go, and find a break before you've laid all the mesh down for your electric radiant heat. Simply test for continuity after laying each piece so you'll know exactly where the break is.
- Drill a hole so that you can put the wires through the floor plate (just above the subfloor) and fish them up through the wall to the junction box.
- Be sure that any wiring for your high temperature alarm is also connected for your electric heating. Also make sure that the cold lead wires do not cross the heating element on their way to the power supply.
- Now it's time to call an electrician who is familiar with your local codes. In some areas, it is required that the two wires from the heating roll and the one wire from the floor sensor be in separate conduits. These wires come to the gangbox, which is where the thermostat will be set. The electrician can double check your work and wire the gangbox.
- Once you get the okay from the electrician, you can apply a thin coating of thinset on top of the mesh and electric heating element. Be careful not to knock or bang the heating element as you do so as this can damage floor heating systems.
- Thinset can take up to two weeks to set completely depending upon the humidity and other factors. The thinset must be fully set before you turn the electric floor heat on! Once the thinset is set, put your flooring material on top of it and you're finished.
When you first turn on the electric floor heating, don't worry - it can take an hour to get really warm and that is normal with all radiant floor heating systems. Your best bet is to turn it up to somewhere between 80-90 degrees and then leave for a while. Otherwise, it's like watching water boil. Come back later to a toasty warm floor, take off your socks, and enjoy.