Underfloor Heating
Underfloor heating systems - which can sit beneath stone, tile, wooden or even carpeted surfaces - will help to keep cold floors and rooms warm; offering an alternative to using radiators to deliver central heating.
There are two main types of under floor heating that you can install:
- Electric under floor heating - which is known as a 'dry system'.
- Water pump driven under floor heating - which is known as a 'wet system'.
See below to find out more about wet and dry systems and the advantages of underfloor heating.
What is Electrical Underfloor Heating?
A series of electric wires are installed beneath or within your flooring as a means of heating the area of the room. The electric system you install will depend on the size of the room and the type of flooring it has. Some options include - loose fit wiring, which is flexible enough to fit into small and awkward places or heating mats that are rolled out to cover larger areas of flooring. Underfloor heating is generally associated with stone or tiled floors but can be fitted in a carpeted room as long as the carpet and underlay isn't that dense it prevents the heat emitting upwards.
How does it work?
The electric heating sheets or cables are fitted beneath the flooring and usually on top of a layer of screed, to ensure that the installation surface is completely flat, and then a layer of insulation to keep the heat travelling upwards rather than downwards. A qualified electrician will need t connect your system up to your electric mains supply and fit a sensor that connects to the thermostat. This allows you to control the temperature and pre-set the underfloor heating system to turn on and off as you please.
Electric systems are generally quite thin which means they are easier and less complicated to install in an existing room than a wet system. This is because a wet system requires space for pipework and could involve the floor being raised. Electric systems are recommended for a retro-fit install.
Costs
Prices for roll out underfloor heating mats start at around £75 per square meter (or less if buying in bulk). You can buy a loose fit kit from around £100 per square meter, however you do need to factor in the cost of insulation boards, screed and heating controls, such as a thermostat as well as labour charges for installers and electricians.
A water underfloor heating system can also sit beneath, stone, tile, wooden or even carpeted surfaces. It offers a heating alternative to radiators leaving rooms spacious and free to rearrange furniture without accommodating radiator space, as well as simply warming up a cold floor for example the bathroom or kitchen.
What are Water Underfloor Heating Systems?
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 solar hot water system. Because the heat emitted from an underfloor system is more evenly distributed than a single radiator, the system can use water at a lower temperature making it a more efficient method of heating your home. According to SAP Standard Assessment Procedure 2009, an underfloor heating system typically improves condensing boiler efficiency by 3% compared to radiators. Underfloor heating is generally associated with stone or tiled floors but can be fitted into a carpeted room providing the carpet and underlay isn't so dense it prevents the heat emitting upwards.
How does it work?
WARM WATER IS PUMPED THROUGH PIPES IN THE FLOOR
Plastic pipes specifically designed for underfloor heating are laid, at even spacing's, under the floor in sand and cement screed. Warm water is pumped through the pipes and the heat from the water transfers to the screed. The entire floor slowly heats up, and once up to temperature, evenly heats the air above it.
THE WHOLE FLOOR BECOMES A LOW TEMPERATURE RADIATOR
Unlike radiators which heat a relatively small and focussed area, an underfloor heating system uses the entire floor area of each room to emit heat so doesn't need to run at high temperatures. Typically, the temperature of the water in an underfloor heating system is between 35 and 55 degrees Celsius - depending on the floor construction.
THE FLOOR WARMS UP
The floor temperature will be between 25 - 33 degrees Celsius when the system is on, which feels nice to walk on and means the air temperature is higher at your feet than around your head. The result is a heating system that is not only highly efficient but extremely comfortable too.
THE AIR IN THE ROOM IS HEATED TO THE DESIRED TEMPERATURE
Thermostats in each room regulate the air temperature by turning on and off the flow of warm water passing through the floor. This allows the temperature of the different rooms or zones in a building to be controlled individually and extremely accurately.
THE WATER IS HEATED BY A BOILER OR HEAT PUMP
Warm water can be provided by either a boiler or a heat pump and is distributed to the underfloor pipework by a stainless steel manifold. The manifold is the hub of the system and is needed to control the flow, temperature and direction of the water.
EFFICIENCY CAN BE IMPROVED
The efficiency of an underfloor heating system can be improved by lowering the water temperature and increasing the amount of pipe in the floor. Underfloor heating systems with pipe at the correct spacing's can operate effectively with flow temperatures as low as 35 degrees Celsius.
INSULATION UNDER THE HEATING PIPES STOPS HEAT BEING LOST DOWNWARDS
For an underfloor heating system to work correctly, adequate insulation must always be fitted below the heating pipes and screed so that the heat is emitted upwards and not lost downwards into the concrete sub base or any air space under the floor.
CHOOSING THE RIGHT FLOOR FINISH IS CRUCIAL
The floor finish must not insulate the screed and stop the heat getting through to the room. Tiles and stone slabs, any wood flooring up to 22m thick and combinations of carpets and underlay up to 1.5 Tog are ideal floor finishes.
Advantages of Underfloor Heating
EXTRA SPACE
With no need for wall mounted emitters, there's no restriction on where you can place furniture in a room. That means every square metre of your home can be fully utilised.
LOWER BILLS
An underfloor heating system is more efficient to run than a traditional radiator system. That's because the water runs at a low temperature and the heat is distributed evenly across the room. It is widely agreed that the temperature in an underfloor heated room can be set 2°C lower than in a radiator heated room and you will feel just as warm.
BETTER HYGIENE
The radiated heat of underfloor heating means dust circulation in a room is minimal and the moisture content of the air is too low to support dust mites. Cleaner air to breathe is clearly beneficial - particularly for asthma sufferers.
MORE COMFORT
Radiant heat will provide the highest comfort levels as your body feels more comfortable when it is heated from the feet upwards. And there's nothing like the feeling of walking around on a warm floor. There is also no possibility of noise such as the annoying ticking made by copper pipes as they expand in floor voids.
OUT OF SIGHT
The heating system is out of sight under the floor - so there are no unsightly wall mounted radiators or emitters to compromise the design and appearance of your property - just a small, stylish thermostat - no bigger than a light switch - in each room.
EASIER TO CONTROL
A thermostat in each room allows the temperature to be controlled very precisely. Programmable room stats offer an even greater degree of control and optimise efficiency. The heating can even be controlled remotely via a computer or mobile phone.
HIGHER EFFICIENCY
The flow temperature of an underfloor heating system can be designed to be anywhere between 35 and 55 degrees. This makes underfloor heating the only choice for anyone wishing to take advantage of the benefits of the latest high efficiency heat pumps.
INCREASED PROPERTY VALUE
Properties with warm water underfloor heating are known to have much higher resale values than comparable properties in the same area. Installing underfloor heating is a smart move for any property developer keen to maximise profit and add a unique selling point to a project.