Radiant heat feels great. There is a reason why people tweet about napping on their floors or post photos of their cats and dogs refusing to leave rooms heated with radiant heat. It just feels amazing! That's the simple part. But what is it, and how does it work? That's a little more technical, so we asked Scott Rosenbaum, Manager of Technical Support at WarmlyYours Radiant Heating, to break it down.
"Radiant heat is heat produced by far infrared light," he explains. Far infrared light is actually the light on the electromagnetic (EM) spectrum of radiation that is beyond the spectrum our eyes can see — right in between visible light and microwaves. The EM spectrum of radiation includes every type of light (a form of energy), which includes gamma rays, X-rays, ultraviolet light, visible light, infrared, microwaves, and radio waves — and visible light actually only makes up a small portion of the EM spectrum, Rosenbaum adds.
Far infrared light is thermal; while we can't see it, we can feel it. Rosenbaum's two favorite examples for how far infrared light — which makes up radiant heat — works are: 1) the sun and 2) a bonfire.
"Think about it. When you walk up to a bonfire, you can't see anything, but you can immediately feel the heat on your skin, confirming the rays are there," he explains. "And when you walk outside into the sun, you don't see the sun's rays hitting your skin, but you can definitely feel them."
Infrared rays are directional. "You need to be standing close enough in front of the bonfire or out in the sun when the rays can actually hit your skin to feel the heat," he notes. "If you step into the shade, or if someone stops to talk to you and stands between you and the bonfire, all the sudden you'll notice you feel cool. That's because the rays are being blocked."
Radiant heat is actually comprised of far infrared rays that travel through the air and begin to directly warm you and the objects in the room, and not the air around you.
So, you might be wondering, do the rays always have to hit you in order to feel the warmth from radiant heat? Rosenbaum explains that homeowners can heat a room with radiant heat because the far infrared rays don't just heat an individual but all the objects in the room (the walls, the floor, the furniture) as well. Once the objects in the room are warm, they, in turn, will all radiate heat as well, which is what actually heats the air and raises the temperature in the room.
"The benefit is that you don't have to try to heat a room as warm as you normally would because the rays still will hit you and keep you warmer while you are in the room," Rosenbaum says. "This saves on your heating bill because it takes a lot more energy to heat the air in an entire room than it does to heat your skin/body while you are in the room."
Back to the bonfire example, while a bonfire could never heat up the actual air in your backyard (the heat all escapes into the open air), it can effectively heat you and keep you comfortable while you are near enough for the far infrared rays to hit your skin, Rosenbaum says.
Many homeowners report noticeable savings from using radiant heat, according to Rosenbaum. "Some report they can turn the heat down 20-30 percent if there is a radiant heat source in the room compared to what they'd use with only alternative convection heaters," he shares. They are comfortable in the room several degrees lower because the radiant heat is warming them and the objects in the room.
"They aren't heating the air, which is then escaping out the windows and cracks in a room," Rosenbaum explains.
"To demonstrate the heating effects, I will have clients stand in front of a radiant heating panel in a cool room," he says. "The air temperature does not change [when] they are standing in front of the panel. It stays cool. But they will feel very comfortable."
It does take a few minutes for the rays to begin to penetrate and gently heat your skin, he cautions. There is no instant blast of heat. However, the far infrared rays' steady, predictable heating is part of the appeal, he says. There are no cold pockets in a room. You are comfortable wherever you move.
So, can you use radiant heat as a sole source of heat?
WarmlyYours' floor-heating systems can be an effective primary heat source, according to Rosenbaum. However, success depends on a few variables, such as the climate you live in and how much insulation your home or your main living areas have. Accounting for those factors will help you determine what is the best heating solution for your unique home. A good place to start is with WarmlyYours' heat loss calculator, which helps you account for those variables. This tool allows trade professionals, designers and homeowners to instantly calculate heat loss information and obtain customized recommendations to meet the specific heating requirements of each project. From there, you can determine if your home is a good fit for radiant heating. When it is, the results are magically soothing heat (just ask all those cats and dogs!).
"There are many happy customers who use radiant heat as a primary source of heat," Rosenbaum says.