Radiant floor heating is a way of heating a home or business with tubes imbedded into the floor which contain heated air or liquid which in turn radiates outwards and ultimately warms the air via the floor.
There are three main types of radiant floor heating:
- Radiant air floors (air is the heat-carrying medium)
- Electric radiant heat floors (electric wires or elements heat up)
- Hot water hydronic radiant heat (heated water in tubing) – also the most common
All three types can be further subdivided by the type of installation: those that make use of the large thermal mass of a concrete slab floor or lightweight concrete over a wooden sub floor (these are called "wet installations"); and those in which the installer "sandwiches" the radiant heat tubing between two layers of plywood or attaches the tubing under the finished floor or sub floor ("dry installations").
Hydronic or liquid systems are the most popular and cost-effective systems for heating-dominated climates. They have been in extensive use in Europe for decades. Hydronic radiant heat systems pump heated water from a boiler through tubing laid in a pattern underneath the floor. The heat from the water radiates through the floor creating a comfortable atmosphere. The temperature in each room is controlled by regulating the flow of hot water through each tubing loop. This is done by a system of zoning valves or pumps and thermostats.