Underfloor heating costs: What it costs to install, run and more
Underfloor heating costs are a major factor when choosing whether to install it in your home. Our expert guide looks at how much UFH costs to install and run
Underfloor heating costs will differ depending on a variety of factors, including the type of underfloor heating (UFH) you specify and whether you are working on an existing home or building a new home.
Underfloor heating has become very popular in recent years, typically offering a more efficient means of heating your home, comfort under foot, while also freeing up the wall space that may have previously been taken up with radiators.
It also adds the opportunity to heat large open-plan areas as well as rooms such as bathrooms and kitchens where appliances and cupboards take up much of the wall area, leaving very little opportunity for the installation of heating emitters.
Here our heating expert David Hilton explains all the underfloor heating costs you need to consider for both electric and wet systems, including installation, as well as the running costs and more.
How much does underfloor heating cost?
Underfloor heating can cost as little as £25/m2 to upwards of £90/m2 to install, depending on the type of wet or electric underfloor heating you specify. We'll dig deeper into these costs below.
It's also worth bearing in mind that UFH can be cheaper to install in new builds and extensions, as it can be designed in and planned for from the outset. Whereas it often necessitates the removal or lifting of existing floor finishes and potentially work to the subfloor in existing homes.
How much does electric UFH cost to install?
Electric underfloor heating can cost as little as £25/m2. However, the answer to this is essentially all about the type of electric underfloor heating system you choose and how much of it you intend to lay.
Electric underfloor heating is effectively electric wires that are installed under the floor, either in the screed or in bespoke panels or films, and the resistance causes the wires to heat up and warm the floor, which then warms the room.
Below are some cost estimates for electric underfloor heating installation for some of the more common electric systems, but bear in mind that the cost will vary depending on the amount of installation work that is required.
You will also need to factor in the costs of your chosen underfloor heating thermostat, an installer if you are using one, as well as the cost of an electrician to sign it off and connect up the power supply.
1. Cost of mesh electric UFH systems
Expect to pay around £50/m2 to £75/m2.
The thinnest system (best suited to tiled surfaces) has wires that are attached to a thin mesh and the whole product is less than 2mm thick. The floor levels are not raised as the tile adhesive is then applied directly onto the mesh and the heater then effectively sits in the adhesive layer.
2. Cost of matt electric UFH systems
Expect to pay around £60/m2 to £90/m2.
For fast installation, a system with a matting can be used that decouples the tiles from the subfloor. The matting is laid on the floor and the wires are pushed into preformed rebate cut-outs.
The adhesive is then applied to the matting and as it is not applied direct to the subfloor potential future seasonal cracking risk is also mitigated.
3. Cost of foil electric UFH systems
There is no requirement for a screed with this type of solution and you can expect to pay around £50/m2 to £80/m2.
Soft finishes such as carpets, vinyl and laminate as well as other floating floors can sometimes be a challenge and foil type systems are designed for this scenario. For more information on this, it's worth taking a look at our guide on underfloor heating with carpet or wooden flooring with underfloor heating.
4. Cost of loose wire electric UFH systems
Expect to pay around £60/m2 to £90/m2.
If the room has irregular shapes or permanent fixtures then a loose wire system is best suited to it. The heater is a durable, but flexible, cable that is stuck to the backing boards and is embedded in the levelling compound or adhesive. Installation is a bit more detailed but the product allows for a lot more design layout variation.
5. Cost of cable electric UFH systems
Expect to pay around £25/m2.
The cheapest electric underfloor heating system is a cable that is bedded in a screed. This system has thicker wires and allows for floor finish changes and screed thickness changes without damaging the wires.
The system is also slow to react and should be designed for long-term space heating and not for quick task heating for short periods of time.
Is electric underfloor heating costly to run?
The running costs of electric underfloor heating can vary depending on how much you pay for electricity, the capacity of the heating system per square meter and how long you leave it on for.
The simple facts are electricity currently costs about 28p per unit (and is set to rise) and a unit is 1 kiloWatt (kW) for one hour so it is referred to as a kilowatt hour (kWh). Therefore if your electric underfloor heating is 125W per square meter then for every 8 square meters of floor you will use 28p per hour that the system is on.
Prices are due to increase in October to around 34p per kWh but you may be on a fixed rate or other rate that could be more than that or less. Look at the cost you are paying as well as the cost that you may be paying in the future.
Check the time of any off peak tariff and also make sure that you actually do have spare capacity from any solar panels if you are calculating them into the equation.
It is also worth bearing in mind that the system is not on all day as the thermostat will only call for heat when it is required. The exact number of hours that it is on will depend on the efficiency of the room that the heating is in but if you need a rough estimate then use 50%, and probably less in a new build.
Is wet underfloor heating expensive to run?
While the initial outlay in installing wet underfloor heating is often more expensive, in the long run a wet system is typically cheaper to run than an electric underfloor heating system.
Wet underfloor heating is typically features lot of pipes that have been installed in the floor structure and as warm water is pumped through the pipes the heat is transferred to the floor and then to the room.
The pipes are laid out in circuits (or zones) and may have one zone per room or even more than one zone in larger rooms. The pipe loop for each zone will need to start and end at a central manifold so there may be areas of convergence and potential additional heat. It is therefore very important to get the layouts designed properly to avoid unbalanced zones and potential hot spots.
What's more, the joy of a wet underfloor heating is that the water can potentially be heated by almost any heat source. You are not limited to direct electric and can actually use a gas boiler, oil boiler, heat pump or a combination of heat sources depending on the heat load. As such, the cost will vary depending on the efficiency of your heat source and the flow temperature.
The real expense is how much energy the home needs. If the room requires 500W to keep it warm then you will want to optimise the way the heat is delivered to the water in the system. If you use direct electric then it will be around three times more expensive than a heat pump or gas. The direct electric heater may cost around 17p per hour but a heat pump or gas boiler should be under 6p per hour.
Is wet underfloor heating expensive to install?
For a wet underfloor heating system you are looking at around £50/m2 to £75/m2 for materials but the underfloor heating installation cost is going to vary depending on the amount of disruption the work will cause, as outlined below.
Much of the pipework can potentially be installed by a competent DIYer but there are also many courses run by manufacturers to give you insight into the tools and techniques required for the installation process.
Quotes for underfloor heating should typically include the design as well as the pipework, underfloor heating manifolds and connections as well as thermostats and controls. Make sure that the controls are compatible with your heat source as well as any other controls that you may already have in other areas of the home.
1. Buried wet UFH costs
Pipes can be clipped to your insulation boards and the screed can be laid over them embedding the pipes in the screed. The pipes can be in parallel lines across the floor or in a circular shape depending on the shape of the floor.
The pipes can also range between 10mm and 16mm diameter with the larger pipes being the most effective but also requiring more installation space.
The cost of the pipework will vary depending on the quality of the pipe and the lengths used. As it is not good practice to have joins in the pipe loops there can be quite a bit of wastage if the loops are not carefully planned.
2. Surface-mounted wet UFH costs
On a joist type floor, such as first floors, underfloor heating pipes can be installed under the floorboards by either fitting them from the room below (before the ceiling is fitted), or by notching the joists and installing the pipework before fitting the floorboards.
Another method is to use an ‘overlay’ system where the pipes are fitted into a preformed board that has rebated grooves for the pipes to be pushed into. The groves are preformed at around 150mm centres (for 16mm pipe) and has a thickness of around 20mm.
Smaller bore pipes will have the grooves closer together and the boards may also be a bit thinner. The boards are often made of high density polystyrene but there are also wood fibre boards, plastic boards and heavier composite boards. As with any additional changes you are making to the structural elements of the home you will need to make sure that any additional weight of the system or notching of beams is within the structural tolerance of the materials.
Which is more expensive: Underfloor heating or radiators?
The simple answer when it comes to choosing emitters is that it very much depends on your home, project and product.
When it comes to installation, adding radiators can be fairly simple compared to adding underfloor heating. There's far less disruption to a room, and a radiator can often be fitted simply where there is wall space (piping can be more tricky but still relatively straight forward). They are also quick and inexpensive to fit.
Adding any kind of underfloor heating meanwhile will require total upheaval of the flooring, which is usually expensive when retrofitting underfloor heating. This is certainly true when it comes to wet underfloor heating. So to install, radiators are far cheaper.
Building a new home or extension, however, provides an opportunity to design in and install underfloor heating from the outset.
When it comes to running costs, wet underfloor heating, if it is installed with good insulation in a well-insulated home can be more energy efficient than radiators. At most, it is estimated to be around 25% more efficient than radiators.
That does differ for electric underfloor heating systems as the cost of running this very much depends on the unit price of electric, which is often far higher. The same of course applies for electric radiators.
The final consideration is longevity and maintenance. Radiators are easily accessible and therefore easier to access to maintain. Underfloor heating meanwhile, if it goes wrong will often require the floor to be dug up. That said, radiators have a lifespan of up to 10 years, while underfloor heating is claimed to have a lifespan of up to 50 years.
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David is a renewables and ventilation installer, with over 35 years experience, and is a long-standing contributor to Homebuilding and Renovating magazine. He is a member of the Gas Safe Register, has a Masters degree in Sustainable Architecture, and is an authority in sustainable building and energy efficiency, with extensive knowledge in building fabrics, heat recovery ventilation, renewables, and also conventional heating systems. He is also a speaker at the Homebuilding & Renovating Show.
Passionate about healthy, efficient homes, he is director of Heat and Energy Ltd. He works with architects, builders, self builders and renovators, and designs and project manages the installation of ventilation and heating systems to achieve the most energy efficient and cost effective outcome for every home.