The default method for heating homes in the U.S. is a forced-air system that, if designed and installed correctly, works well at keeping residents warm. But those looking to add supplemental heating as well as an option buyers will love should consider electric radiant flooring. Anyone who’s walked on a radiant floor knows it’s extremely comfortable. And now manufacturers have made them more energy efficient.
According to the Radiant Panel Association in Baldwinsville, N.Y., radiant heat uses a warm surface to transfer heat into a space rather than moving heated air. The majority of the radiant heat then travels through the air and warms other surfaces. “This natural heat transfer is both comfortable and energy efficient,” the association notes.
Because a radiant system heats the space directly above the floor, a radiant-heated room may feel warmer than a forced air system because heated air rises and makes the lower area seem cooler.
“[It’s] more efficient than baseboard heating and usually more efficient than forced-air heating because no energy is lost through ducts,” the Energy Department’s energy-efficiency and renewable energy office says. Plus, people tend to feel more comfortable if their feet are warm.
Of the three types of radiant systems, the electric (or dry) system is by far the easiest and, perhaps, most economical to install. “Electric radiant floors typically consist of electric cables built into the floor,” says Toolbase, the technical information arm of the NAHB Research Center in Upper Marlboro, Md. “Systems that feature mats of electrically conductive plastic are also available and are mounted onto the subfloor below a floor covering such as tile.”
Dry systems are desirable, manufacturers say, because they aren’t moving dust around and therefore offer an indoor air quality benefit. They are quieter, too, and can radiate heat long after the system is turned off. In addition, a dry radiant floor does not require self-leveling compounds, concrete, or mortar. The mats simply install under ceramic or stone tile, floating floors, engineered wood products, and even carpeting.
Norfolk, Neb.–based MP Global Products says, for example, that its QuietWarmth dry system is “maintenance-free, has no liquid components and so can’t leak, and does not require annual tune-ups that hydronic heating systems call for.”
The systems are also affordable. Material costs for an electric radiant bathroom application range from $500 to $1,000, which includes the mat and thermostat, says Kevin McElroy, vice president of sales for Nuheat in Delta, British Columbia. “The operating cost is usually less than the light bulbs in the room,” he adds. The systems are easy to install, requiring only a simple wiring connection and layout of the radiant mesh.
But electric radiant systems are not for every situation. “Because of the relatively high cost of electricity, electric radiant floors are usually only cost-effective if they include a significant thermal mass, such as a thick concrete floor, and your electric utility company offers time-of-use rates,” Toolbase says. Time-of-use rates, the group explains, allow you to heat a concrete floor during off-peak hours. If the floor’s thermal mass is large enough, the heat stored in it will keep the house comfortable for eight to 10 hours.
Electric radiant heat may be inappropriate for a whole house, but it’s great for small applications. This may explain why 80 percent of Nuheat’s (and most of the industry’s) products go into kitchen and bathroom remodels, McElroy says. But the costs versus the benefits to customers present a genuine opportunity for new-home builders.
For one, radiant is an easy upgrade. It’s inexpensive and can be completed in a short time, but the benefit to the home buyer is priceless. In addition to the luxurious feeling radiant provides, the buyer gets a nice source of supplemental heating.
And, it may not be a hard sale to make. The industry says more consumers are finding out about the benefits of a warm floor and are choosing it more often as an option.
“There has been a sharp increase in areas like foyers, extensions to homes, and basements that are getting finished,” McElroy says. “This is driven by [growing] awareness of the category and the fact that these areas tend to be hard to heat with conventional systems.”