Radiant floor heating is gaining in popularity

By Catalogs Editorial Staff

Have you thought about radiant floor heating?

Hydronic, or radiant floor heating is a method of heating a home, shop, or other building with the heat concentrated in the floor. It works by embedding special tubing in a concrete foundation or in a thin concrete mixture on top of a wood-framed floor. Heated water flows through this tubing, warming the thermal mass of the concrete.

Most common heating systems such as forced air furnaces use moving air (forced convection) to deliver the heat to a room. There are some problems with this system. First, hot air rises, therefore much of the heat ends up at the ceiling while the floor remains cold.

Second, as air moves around the room, it travels in warm and cool currents, resulting in drafts as the air comes in contact with our skin. Also, because the heated air is delivered from only a few strategically placed registers, even heating of the room is virtually impossible. There are inevitable warm and cool spots within the room.

Forced air furnaces work in blasts. The hot air is forced into the room for a short time and then the flow of air stops. The air rises and spreads out, loses its heat, and cools off. The room drops in temperature and the cycle repeats. This causes temperature swings within the room as well as lower-level rooms to be cool and upper-level rooms to be hot. ~If you’re like most people, you probably assume that with radiant floor heating the warm floor heats air which rises to heat people. This is only partly true. A small percentage of the heat transferred to the room from a radiant floor actually comes from heated air. In fact, the air temperature ceiling to floor and throughout the room never varies more than one or two degrees.

The obvious question is then, “where does the heat come from?” Radiant heat is a little more difficult to understand although we experience it daily. The air in the big outdoors is primarily heated by its contact with the heated earth. When we step outside on a warm cloudy day, the warmth we feel is the radiant energy coming directly from the sun. It is exactly that form of heat which is radiated from a warm floor when a radiant floor heating system has been installed.

Although around for many years, the expense and limitations of early U.S. systems contributed to the waning interest in radiant floor heating in the mid-sixties. Although radiant floor systems have continued to be used over the years on a limited basis, it was not until the advent of synthetic rubber and plastic tubing suitable for the job that there began a renewed interest in radiant floor heating.

Since the interest was rekindled in the late seventies and early eighties, a new industry has grown up around radiant floor heating. People are rediscovering the extreme comfort and energy efficiency of this type of heat. The cost effectiveness of new technologies and construction techniques has made the comfort of radiant heating affordable and adaptable to almost any situation.

Alternative energy sources such as solar and geothermal are also a very good match for radiant floor heating. Radiant floors use relatively low water temperatures which makes very efficient use of these types of heat sources.

The ultimate selection of the heat source is usually left up to the engineer or installer on the job. Unless the customer makes a specific request, the installer will probably choose his favorite product or at best give the customer a choice of several. The important factors in choosing a heat source are the fuel used, energy efficiency of the unit, serviceability and cost. Highly efficient units generally cost significantly more than moderately efficient units. The choice becomes one of investing money at the time of installation and paying higher utility bills. Over the years, your savings can be considerable. The big advantage of radiant floor heating is that no matter which boiler you choose, in all probability it will consume less energy than if it were connected to any other type of heating system.

Air conditioning and heating are distinctly different and opposing functions. With a central cooling system, independent of the heating system, ducts can be routed through the attic to serve rooms from inside walls. This technique reduces installation costs and eliminates unsightly ducts in the basement ceiling.

With the growing concern for indoor air quality, the old centralized combined heating and cooling system may become a thing of the past. New technology has made so many things possible today to improve the efficiency of heating our homes; just one of which is radiant floor heating. If you’re like most people, you probably assume that with radiant floor heating the warm floor heats air which rises to heat people. This is only partly true. A small percentage of the heat transferred to the room from a radiant floor actually comes from heated air. In fact, the air temperature ceiling to floor and throughout the room never varies more than one or two degrees.