Radiant Floor Heating

Keeping your feet warm saves energy as it provides the ultimate in comfort

The best heating system a house can have is the one you don't realize is there. No radiators, No vents, No dust-spewing ductwork Just an even blanket of heat, right where you want it.

That's the appeal of radiant floor heating, It's truly invisible. But a radiant heat system has more than just aesthetics going for it. It's also a highly efficient way to heat a house, increasing comfort as it reduces energy costs.

In a radiant setup, the warmth is supplied by hot-water tubes or electric wires buried underneath the floor. As the invisible waves of thermal radiation rise from below, they warm up any objects they strike, which radiate that captured heat in turn. Though the air temperature remains relatively constant, you stay comfortable because the surrounding surfaces aren't stealing warmth from your body.

There are two basic types of radiant floor heating that supply this gentle, even warmth: hot water or electricity. Electric radiant, which uses zigzagging loops of resistance wire, is ­generally retrofitted to a single room, such as a bathroom or kitchen. (See "The Floor Electric," above.) Hot-water "hydronic" systems—the most popular and cost effective way to heat an entire house—circulate water from a boiler or water heater through loops of 1/2-inch polyethylene tubing. The flexible tubes can be installed in a variety of ways: on top of the sub-floor in grooved panels or snap-in grids; clipped ­into aluminum strips on the underside of the floor; or embedded in poured concrete. Once the system is in place, you can cover it with most types of finish flooring, including hardwood and tile. Carpet, however, can be tricky, especially if it has thick padding underneath. "If the floor is too well insulated, radiant heating really ­doesn't make sense. "It's like putting a sweater over a radiator."

Hot-water radiant costs more to install than other types of heating systems. Whether you're starting from scratch or retrofitting, and where you live. (New builds where the tubes are buried in concrete slab tend to be the least expensive). And you'll still need a separate air-conditioning system for cooling. But if the price tag puts you off, consider this: Once it's up and running, a radiant heat system can be up to 30 percent more efficient than forced-air heating, depending on how well insulated a house is. And there's no comparison when it comes to comfort. In that category, radiant always wins, feet down.