In floor heating, rooms are heated by (lukewarm) water circulating in continuous pipe loops embedded in the concrete floors. To ensure total reliability, there are no joints in the pipes in the floors. The floors reach a pleasant temperature of around 27°C, and produce a wonderful even heat at all points in the room.
Virtually any floor covering can be used from the obvious such as stone, tiles etc., but many people are surprised to see that the seemingly unlikely combination of wooden floors and Underfloor heating are growing hugely in popularity. Most solid woods can be used once dried slowly over the heated floor before fixing (they will shrink a little width-ways before fixing), alternatively some manufacturers of wooden floors such as Admont with their three-layer wide-plank floors (also supplied by Unipipe) carry a warranty for use with this type of heating.
These Austrian Admont boards, in either six or eight inch widths, can also be floated on a recycled paper underlay, or bonded straight onto a concrete floor. Whilst this type of flooring is more expensive per square metre initially, there are cost and time savings in construction due the lack of requirements for battens or joists.
In parts of the house needing greater levels of heat such as near large windows or in the conservatories pipes can be laid at closer spacing, so giving greater heat where required.
So why does floor heating cost less to run? There is a combination of reasons.
As the heat literally radiates from the ground, the room is warmer at lower levels and cooler at the ceiling. This is the opposite from radiator heating with which the hotter air rises directly up to the higher levels in the room. In terms of comfort, this is also an ideal temperature profile, having a warm body and a cool head! This Guardian article has more on this topic. Many churches and older period buildings are now using floor heating, and as a result, take advantage of even bigger energy savings because of their lofty ceiling heights.
As mentioned above, the heat from the floor is radiant or ‘reflected’ onto the occupants. This phenomenon allows one to feel more comfortable with a slightly lower actual air temperature. With convected heat such as that from radiators, all the air in the room must be heated, as it heats the occupants by the warm air in contact with them. A side benefit from this is that a building using floor heating has a much less stuffy atmosphere and is healthier.
The water in the floor loops is at a much lower temperature than conventional heating. (Usually around 45°C as opposed to 80°C) When you couple the extremely low running temperature of the system water to a condensing gas boiler, or geo-thermal heat pump, you can have stunning reductions in energy consumption. Unipipe can provide at no extra cost, specialist design advice and schematic drawings, for these installations.