There are three types of radiant floor heaters – radiant air floors, electric radiant floors and hydronic radiant floor.
Each of the type is further subdivided by the kind of installation – wet and dry installation. In wet installation, a large thermal mass of concrete slab floor or lightweight concrete is mounted over a wooden subfloor. On the other hand, in dry installation, the installer sandwiches the radiant floor tubing between plywood layers or fastens the cable under the finished subfloor.
Radiant air floors are rarely installed in residential houses. Air cannot hold huge amounts of heat, making them, not so cost effective. Electric radiant floors are cost effective if the electric company will give you credit for time-of-use rates. This will allow the concrete floor to absorb heat between 9 pm to 6 am, which are considered off-peak hours. The heat accumulated will keep your home comfortable for 8 to 10 hours without electrical input. But this is only possible if the thermal mass of the floor is large enough. You can save money as compared to heating during peak hours. Lastly, the hydronic (water) systems have been used extensively in Europe for decades now. This heating system has become popular because it is cost-effective. From a boiler, heated water is pumped through tubing installed beneath the floor. Regulating the hot water flow in each tubing loop allows temperature control in each room. You just need a system of zoning valves or pumps and thermostat.
Wet installations, oldest form of modern radiant floor systems, make use of embedded tubing in the concrete foundation slab or in a lightweight concrete slab on top of a subfloor or over a previously poured slab. Additional floor may be required if the new floor does not stand on solid earth, as this would mean added weight. To find out the carrying capacity of the floor, a professional engineer should be consulted.
Recently, dry installation is now more preferred than wet installation because of innovations in floor technology. It is cheaper and at the same time faster to build. This type of installation may include tubing suspended beneath the subfloor between the beams supporting ranged from wall to wall. Drilling is necessary through the floor joists for the tubing installation.
To ensure the flow of heat upwards, reflective insulation is a required feature of the system. In instances in which the tubing is installed above the floor, aluminum diffusers contain the tubes which allow the even distribution of water’s heat across the floor. The furring strips protect the tubing and heat diffusers from the weight of the new subfloor and finished floor area.
A company made an innovation by using plywood as a subfloor material with built in tubing grooves and aluminum heat diffuser plates. The maker of this technology asserts radiant floor system becomes less expensive to install and faster to react to temperature stimuli. The heat transfer feature is said to have greatly improved, thus the tubing is used half as much.
Floor Coverings
Almost any floor covering may be utilized for radiant floor heating system. Ceramic tile is the most commonly used. Vinyl and linoleum covers, carpet, wood and bare concrete are usually specified. But whatever covering will be used for the floor, you have to bear in mind that floor coverings have insulating effects, thus they may reduce the system’s efficiency since heat flow is slowed down. As a result, fuel consumption rises.
If carpeting is preferred, thin carpet with dense padding is advisable. As much as possible, go for little carpeting. Rooms with floor coverings should have a different set of tubing loop for a more efficient system in these areas. Covered floor require more heat from the water flowing beneath it.
Instead of solid wood, laminated wood flooring is recommended for most floor references. The drying effects of heat may shrink or crack the wood. For the installers who still choose solid wood flooring, it is suggested that they familiarize themselves with radiant floor systems. To assist in resolving problems related to it, manufacturers and manuals must be consulted for guidelines.