Underfloor heating systems Water underfloor heating
A water underfloor heating system, like its dry electric underfloor counterpart, can also sit beneath stone, tile, wooden or even carpeted surfaces.
It offers a heating alternative to radiators in bathrooms, kitchens, an entire house - or simply a means to warm up a cold floor on an early morning in winter.
Water underfloor heating explained
With a water-based underfloor heating system, a series of pipes connected to your boiler circulate warm water throughout the floor to heat the space. Alternatively, you can connect the water underfloor pipes to a or solar water heating system. You'll need to check your boiler is
Because the heat emitted from a underfloor system is more evenly distributed than a single radiator, the system can use water at a lower temperature, making it a more efficient way of heating your home. According to Standard Assessment Procedure 2009 (SAP), an underfloor system typically improves condensing boiler efficiency by 3% compared to radiators.
Underfloor heating is generally associated with stone or tiled floors, but you can even fit it in a carpeted room - you'll just need to ensure that the carpet and underlay isn't so dense that it stops the heat moving upwards (a tog of no more than 1.5 is a general rule of thumb).
How it works
There needs to be enough space to fit the piping, meaning you might have to elevate the floor level - not always possible if you're retrospectively installing underfloor heating to an existing bathroom or kitchen.
For this reason, water-fed systems are best suited to new floor constructions, where the floor itself can be designed to hold the pipework, and be adequately insulated to ensure the heating doesn't escape downwards.
According to SAP 2009 standards, there are different rates of responsiveness and efficiency depending on what the pipes are laid in. It recommends using pipes in combination with an insulated timber floor for the best results, followed by pipes in screed.
Unlike using ready-to-roll electric mat - which confident DIYers could lay themselves - installing a water underfloor system should only be fitted by a professional.
They'll be able to advise you on the best type of underfloor heating for your room size and shape. They will also need to test your boiler to check it can support the system.
You can find heating engineers or underfloor heating specialists in your area using Which? Local, our unique trader recommendation service.
Water underfloor heating costs
A water underfloor heating system is more expensive to fit than an electric kit and you'll need a heating engineer or underfloor heating specialist to complete the installation, which can run into thousands of pounds if you're installing a whole property system.
The Energy Saving Trust (EST) says water underfloor heating is typically more energy efficient than radiators and therefore less to run - though the savings figure will depend on how energy efficient your home is.
The savings are pretty modest though. According to the EST, when comparing a new condensing gas boiler and radiators with one using underfloor heating, a typical gas-heated three-bedroom semi could expect to see a difference of around £20 a year on its energy bills.