Hydronic Underfloor Heating Systems
Heated water is circulated along reinforced polythene piping with separate circuits for different rooms and areas. Each circuit is connected to a manifold with regulating valves and a thermostat so different rooms can be heated to different temperatures and at different times, minimising unnecessary energy use.
The manifolds distribute water at temperatures of 35-60ºC which in turn heats the floor to a comfortable constant between 18-29oC. When the room reaches a pre-set temperature the thermostat signals to a valve on the manifold to close the circuit in that room. There are three main types of wet underfloor heating:
This is the common choice for new build properties. The underfloor heating is permanent as it is built into concrete or screed floors. Insulation is laid first, with the pipes then put down in a specific pattern before the concrete or screed is poured. Many types of floor finish can then be overlaid including wood, stone, tiles, vinyl or carpet, though careful consideration is needed to ensure it will not be affected by the heat and/or will not insulate against it.
The heating system is inserted between the joists or battens in the suspended floor, with suitable insulation below. The casing usually consists of a tongue and groove floor board to allow a range of floor coverings to be fitted, with the same considerations as above.
This is the quickest type of underfloor heating to install as there is no requirement for screed or concrete to set. This system can also be used above an existing solid or wooden floor and so is ideal for retrofitting. However, the floor level could be significantly raised. The pipes are inserted into preformed heat plates which rest in grooves in the insulation.