Electric infloor heating vs. forced air heating systems
Q. We are adding a family room and a bedroom to our house. We are considering electric radiant infloor heating. Is it costly to operate and does it work well with carpeting?
A. Electric infloor heating is one type of electrical resistance heating. Resistance heating is typically the most expensive to operate, but infloor electric radiant heating is the exception. In addition to keeping your feet toasty warm, it offers some advantages over forced air heating systems, such as gas or oil furnaces and heat pumps.
Since there will be no ducts in your new rooms, consider adding a small mini-split ductless air-conditioning system for summer cooling. For just slightly more initial cost, install a heat pump model. This can also be used to heat the rooms during mild spring and fall weather.
Although it is most often used for concrete and tile flooring, electric radiant infloor heating can also be used under carpeting, hardwood and laminate flooring. Each type of flooring requires a different design of heating materials. All of them are typical less expensive to install than a standard ducted heating system.
The primary advantage of infloor radiant heating is improved comfort. It sounds as if you sense that when your feet are warm, you feel warm all over. This benefit of radiant heating allows most people to have the room air temperature lower and still be comfortable. Anytime the thermostat is set lower, less energy is needed to keep the room warm.
With the low intensity heat emanating from the floor and less air movement, there is less heat stratification in the room. This means less hot air ends up at the ceiling and more down closer to the floor where people are. There also often are less dust and particles floating in the room air.
Most room additions are done over a concrete slab, so installing electric heating cable is effective and a relatively simple project. The electric heating cable is usually placed in a serpentine pattern and then covered with thinset or other floor leveling material. The thermal mass of the slab yields even heating, but the temperature reacts slowly to wall thermostat changes.
The above installation technique is also common in bathrooms and kitchens where ceramic tile is used for the flooring surface. The infloor heating system manufacturer can do calculations to determine how much cable you will need for your climate and size room. Many of the radiant floor heating systems are designed for do-it-yourself installation.
When installing under carpeting, hardwood or laminate flooring, the heating cables are installed in rolls of fiberglass mesh and are easily interconnected. Contact the flooring material manufacturer to make sure the maximum heating mesh temperature does not exceed the maximum allowable for the flooring material.
WarmlyYours provides a do-it-yourself electric radiant floor heating kit with heating wires in foil. It is wafer-thin and ideal for use between carpet padding and the carpet. Heatizon offers a kit with thin mesh which is stapled to the subflooring. It is low-voltage, making it very safe for simple installation.
The following companies offer electric infloor heating systems: Calorique, (800) 922-9276, www.calorique.com; Heatizon, (888) 239-1232, www.heatizon.com; Orbit Radiant Heating, (888) 895-0958, www.orbitradiantheating.com; Suntouch, (888) 432-8932, www.suntouch.net; and WarmlyYours, (800) 875-5285, www.warmlyyours.com.
Q. I have a water heater insulation jacket, but it's not long enough to cover my entire new electric water heater. Will it be effective if the water heater is covered only three-quarters of the way down?
A. Although it is best to insulate the entire tank, your water heater jacket should still be effective. The water at the top of the tank is hotter than at the bottom.
If you have some old fiberglass or stone wool wall insulation, wrap a layer of it around the bottom uncovered area. Face the vapor barrier to the outside and use it to staple the ends of the insulation together. A gas water does needs an open area at the bottom for combustion air.
• Write to James Dulley at 6906 Royalgreen Drive, Cincinnati, OH 45244 or visit dulley.com.