There are two methods of installing these heating systems: wet and dry. 

Wet: The wet method is most often used on ground floors. It does a better job at retaining heat because it isn’t trying to heat an air space as well as a room. When installing a radiant system using this method of installation, tubing (if the radiant floor system is hydronic; wires if it’s electric.) is laid over insulation and and tied to rebar. All this is topped with a poured concrete slab. This is the oldest method of installation.

Dry: This is a relatively new technique for installing radiant floor systems. However, they are quickly gaining popularity because of their quick and cheap installation. When using the dry method, tubing or cables are suspended in floor joists. Reflective insulation is installed to direct the heat upward.

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Radiant heating supplies heat directly to the floor or to panels in the wall or ceiling. It’s more efficient than baseboard heating, and usually more efficient than forced-air heating because energy isn’t lost through duct-work. This type of heating can be very good for people with severe allergies because there isn’t any moving air involved.

There are three main types of radiant flooring: Air-heated, Electric, and Hydronic.

Air-Heated Radiant Floors: This type is not used very often because air doesn’t stay warm enough long enough. It’s not cost effective.

Electric Radiant Floors: These are made up of electric cables built into the floor although there are systems that use mats placed on the subflooring. This option isn’t very cost effective either, but it’s better than the air-heated floors.

Hydronic Radiant Floors: This is the most popular and cost-effective option. Hydronic systems pump hot water through pipes or tubes laid out in a pattern under the floor. The cost of this type of system varies by location, size, type of installation, floor covering, how difficult your site is to get to, and the cost of labor.

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