Underfloor heating in homes may seem like a recent development, but Romans used hot water and steam to do it 2000 years ago. We don’t use steam for radiant heating these days; we use warmed liquid circulating in pipes (hydronic) or electrical heating elements.
Hydronic systems are difficult to install. You need skilled designers and tradespeople familiar with boilers, circulators, controls, fluid pressures, temperature, and so on. I use electric systems, which have fewer components and are easier to install. Electric systems consist of flexible heating elements made of cables, cable mats, bronze mesh, and carbon films, all of which can be installed directly under floor finishes. I use different kinds depending on the shape of the room; some are better for heating all the nooks and crannies.
A variety of thermostats work with heated floors. I always use Energy Star programmable thermostats. I install backlit thermostats that are easy to adjust at night; some are bright enough to use as a night light. These units can tell you the ambient (air) temperature as well as the temperature of the floor.
Why use underfloor heating? It can heat flooring materials such as tile, slate, terrazzo, and concrete, which are otherwise cold. Masonry materials have very low VOC (volatile organic compound) emissions compared to other flooring. Since the floor warmth minimizes moisture, floor heating also helps suppress mold, bacteria, viruses, and dust mites. It delivers the heat lower in the room, where you are, not up at the ceiling. It can be used to heat only the zones of your house that you’re using and to warm up the floor when you plan to be in the room, so it saves energy. You can’t burn yourself or trip over it, so it’s safe, and it’s silent.
I haven’t done a master bath floor in the past two years where I didn’t install underfloor heating. Since there are no moving parts, the systems are reliable. The only part prone to failure (assuming proper installation) is the temperature sensor in the floor. I always install two, so that if one fails, there’s a backup. It’s important not to install the sensor too deep in the floor. As with anything, experience is the best teacher. I’ve installed hundreds of heated tile floors, and learned something new every time.
So you could say I’m a big fan of heated floors. I mean, who wants to step out of the tub onto cold tile?
