How do people with tiled-floor kitchens have toasty warm feet without wearing socks and slippers in the middle of winter? In a nutshell, they have radiant floor heating: tubing containing heated water is laid beneath the floor. The tubing heats the floor, which, in turn, heats everything that touches it—including the air—so that the heat radiates through the room from the floor up.
Such heating can be fitted retrospectively on a limited basis, but it’s easier to install during new construction.
If you’re installing radiant heating throughout the building the best choice will be a hyrdronic system (ie hot-water tubing) powered by either a propane-fired or an oil-fired boiler. The tubes can be laid either directly beneath the subfloor or sandwiched beneath the subfloor and a thin (usually about 2”) layer of lightweight concrete. In this latter set-up, known as a ‘wet installation,’ the concrete slab becomes a thermal mass, retaining the heat beneath the floor for slow release.
Radiant heating comes with a higher up-front cost than the equivalent traditional baseboard or radiator system but it can last up to 40 years, is silent, can save you as much as 40% in energy costs, and significantly reduces dust, which is a big plus for allergy sufferers.
Finally, if you are considering radiant heat in an existing house but do not have a boiler, you can either install an electric in-floor coil system or, if it’s for a small space—such as a bathroom—you can heat the tubes with an independent hot water heater.