The air in the room becomes uncomfortably stratified: Your head can be bathed in warmth while your toes lie in the frozen zone. Air blows out of the registers at a well-baked 120 degrees, rises to the top of the room where it quickly sheds heat, then drops back down as it cools. How does it differ from conventional heating?Д¬ontrast that with what happens in a conventional forced-air heating system, the kind found in most American homes. Though the air temperature remains relatively constant, you stay comfortable because the surrounding surfaces aren't stealing warmth from your body. As the invisible waves of thermal radiation rise from below, they warm up any objects they strike, which radiate that captured heat in turn. In a radiant setup, the warmth is supplied by hot-water tubes or electric wires buried underneath the floor.

It's also a highly efficient way to heat a house, increasing comfort as it reduces energy costs. But a radiant heat system has more than just aesthetics going for it. That's the appeal of radiant floor heating, says This Old House plumbing and heating expert Richard Trethewey, who has long been a fan. This Old House plumbing and heating expert Richard Trethewey helps guide you through two types of heated floors in terms of cost, installation, and energy efficiency to select the right one for your house. Just an even blanket of heat, right where you want it. No dust-spewing ductwork to run up your allergists' bills. No vents whooshing like a jet preparing for takeoff. The best heating system a house can have is the one you don't realize is there.

Radiant heating system