There are generally three types of radiant floor heating systems. Let's take a look at them and to get a general idea of their purposes and efficiency rates.
Air-Heated Radiant Floors
Radiant air floors are rarely installed in home because they are just not very cost efficient. That's because air simply does not hold large amounts of heat. You can always combine them with solar air heating systems. But, solar power is only useful during daylight hours. Therefore, the system would be ineffective at night and on cloudy, overcast days. That's when heating demands are highest. Air-heated radiant floors, combined with solar air heating systems
is only recommended for situations where heat is only needed during the day. One example would be an office building that closes at dusk.
Electric Radiant Floors
Electric radiant floors usually require electric cables that are built directly into the floor. They are not very cost efficient, unless there is a thermal mass included. This could be thick, concrete flooring. It's also helpful when your electric company bills on “time-of-use” rates. This allows you to “charge” the concrete flooring with heat during low usage hours. This is generally 9PM to 6AM. The heat is then stored in the concrete, which is used to warm the house for eight to ten hours without anymore “charging.” This helps to keep your electric costs down because you are not using this energy during peak electric rate hours (daytime).
Electric radiant floors are a great choice for homeowners who have added on to the home. Sometimes, it's not practical to extend your home current heating system to the new addition to the house. But, you don't want your new den, home office or studio to always be cold and uncomfortable. Another option in this case is to look into mini-split heat pumps
Hydronic Radiant Floors
Hydronic (liquid) systems are the most cost efficient radian heat systems. They also seem to be the most popular for very cold climates. With the hydronic radiant floor system, heated water is pumped from a boiler, into tubing that's been laid under the flooring. Typically, the room temperatures are controlled by the regulation of the hot water that flows through each looped tube. The installation costs depend on the home's size, the way the homeowner wants the system installed, the type of flooring cover, site remoteness and the labor costs being charged by your installer.
For more home heating ideas, check out Chimney-Free Gas Fireplaces