Electric radiant floor heating systems can be installed under tile or carpeting. They are most commonly used in kitchens and bathrooms.

The same type of radiant floor heating that is found in upscale hotels has been installed in existing and new home construction for many years. Although it is most often installed under tile or other solid flooring, some radiant floor heating systems are designed to be laid underneath carpeting. Even installing it under tile is not a terribly difficult job.

Electric radiant floor heat is one of the most comfortable heating methods available for two reasons. First, the heat is concentrated down near the floor where you are. With forced air heating, the warmest air often ends up stagnating near the ceiling, well above your head. Second, this is radiant heat, which directly warms your body, not just the room air, similarly to when you are standing in the bright sun on a cold winter day. />

Even though electric radiant floor heating is a form of electric resistance heating, it can be relatively energy efficient. Instead of having to heat the room air to a temperature for your skin to feel comfortably warm, as with other heating systems, radiant heat allows you to feel comfortable at a lower room temperature. The amount of heat lost from your house is a function of the indoor temperature, so by keeping it cooler, yet comfortable with radiant heat, less heat is lost.

Electric radiant floor heating can be used in just one or two rooms while you still use your furnace or heat pump for the majority of the home heating. By installing it in the rooms your family uses most often, especially at night when they are less active, you should be able to set your regular furnace thermostat lower, still be comfortable and save energy overall. This is most commonly done in bathrooms or kitchens with tile floors.

Several designs of electric floor radiant heating systems can be applied to residential construction. Some are best in new construction under tile, while others are designed to be placed under hardwood floors or between the carpet pad and the carpeting. Some systems are sold in color-coded kit form, which includes all the wiring, heating elements (pads or cables) and a wall thermostat. Each room will have its own thermostat, so you can zone heat your home for additional comfort and energy savings.

Most systems can be powered by standard 120 or 240 volts, so special house wiring is not needed. The simplest control is a standard line-voltage on-off thermostat. Some have a built-in thermometer, while others have graduations on a dial from warm to hot. For the best comfort and efficiency, computerized digital thermostats are available. These sense floor and air temperatures to precisely control the amount and timing of heat. These also allow you to vary the temperature for four different periods throughout the day and night.

A common radiant system for tile floors uses heating cable beneath the tile. The manufacturers can advise you or your contractor about how much cable is needed to crisscross the floor to provide adequate heating. Once the cable is attached to the subflooring, a thin layer of thinset is spread on top and the tile is applied. If your house is built over a basement, some cable systems are designed to also be installed between the floor joists from below.

Another option is fiberglass mesh with the heating cable already woven through it. This makes installation much simpler. The mesh and cable is only 1/8-inch thick so it easily fits under tile, stone or hardwood floors. Since the density of the cable per-square-foot is fixed with this method, you have less flexibility for the total heat output in a room.

There are several options for under-carpet applications. In one, a fine heating element is sandwiched between several layers of aluminum foil laminate. It is only 1/16-inch thick, but durable, and is placed between the carpeting and the padding. Another design for use under carpeting, hardwood or floating floors, uses a mesh screen to create the heat. The standard house voltage is stepped down to a safe, low voltage, which flows through the heating screen. This is very easy to install.

Write for ) Utility Bills Update No. 888 – a buyer’s guide of nine electric warm floor system manufacturers listing design types, sizes/heat outputs, common applications, comfort controls, and installation instructions. Please include $3 and a business-size SASE.