How Does Underfloor Heating Work?

Underfloor heating is an energy-efficient way to heat your home. It eliminates traditional clunky radiators and replaces your central heating with a hidden underfloor system that will warm your rooms to the perfect temperature.

Sounds great, but how does it work? We will look at the different types of heating systems and how underfloor heating works. We'll also compare which is better, why it's more efficient than your old radiators, and the typical cost of underfloor heating.

Discover more related articles on underfloor heating boiler requirements, where you can buy thermostats online, and if you need radiators with underfloor heating.

Types Of Underfloor Heating Systems

Electric underfloor heating

Electric underfloor

Electric underfloor heating systems or 'dry' underfloor heating systems heat your room(s) by using a series of electric heating mats, sheets, or wires. These are placed either within or below your flooring. There are three central electric systems to choose from.

Matting is suitable for larger regular-shaped rooms with stone or tiled floors. There is also the Foil Mat, which is specifically designed for laminate flooring. Finally, the Loose Wire system is good for oddly shaped rooms and suitable for stone and tile floors.

'Dry' systems work better in small spaces such as en suites as it can be fiddly to install a 'wet' underfloor heating system in these spaces.

Water underfloor heating

Wet underfloor

A water underfloor heating system or 'wet' system links directly to your central heating system. A subfloor will hold a network of pipes running heated water across your floor. The warm water systems are designed to work best with your flooring type and the subflooring options.

This type of floor heating will keep your heating bills down, and although it is more expensive to set up, it is cheaper to run than the 'dry' system.

How Does Electric Underfloor Heating Work?

A series of electric heating sheets or wires are pre-spaced on foil or in a mat and are installed under your floor. It is controlled by the thermostat, which a qualified electrician must install. This kind of underfloor heating can be fitted easily as long as you have an electrician provide the thermostat.

It is inexpensive to install. However, it can be more expensive to run than water underfloor heating. You can also install electric underfloor heating upstairs.

How Does Water Underfloor Heating Work?

As already mentioned, this type of underfloor heating is connected directly to your central heating system. The water will be heated by the heat pump or boiler then travel through the underfloor heating pipes on your floor.

Your floor will also be insulated to prevent heat from escaping. The warm water underfloor heating is slightly more challenging to install than the electric system, but it is less expensive to run. This helps keep your underfloor heating costs down and offsets the installation price.

Which Flooring Materials Are Used With An Underfloor Heating System

Floor materials

Any floor finish can be used with an underfloor heating system. However, the more conductive the material, the better the result. Tile and stone are highly conductive materials making them the perfect floor covering.

They also retain the heat, making efficient flooring choices for energy costs. Some wood flooring has conductive properties depending on the wood, the thinner and denser the wooden floor, the better at conducting heat.

Wooden floors may change their appearance due to the moisture content from heating, so check with the floor manufacturer. It is essential to get the thickness of the wood right so it doesn't act as an insulator blocking the heat.

You may choose to have a carpet. However, the carpet is an excellent insulator, so it will need to be a low tog with a thermal resistance of 1.5. The higher the thermal resistance rating, the lower the heat output, so the more pipes you may need to compensate, which increases your cost.

Are Underfloor Heating Systems Better Than Radiators?


Should underfloor heating replace radiators? If you install underfloor heating, it is out of sight and doesn't encroach on your wall space like the traditional radiator system. Eliminating the bulky old radiator system can be helpful in that you will save 10% of wall space, meaning you have more options for placing furniture.

It also eliminates the risk of small children burning themselves on a hot radiator. Rather than setting your radiator's heat high to try and heat the room, the entire floor space is the heat source.

This means warm floors and the hot air filling your room to the desired temperature with ease. Your floors will be nice and friendly when you get up in the morning, and there will be no cold spots in your rooms.

This also means it is efficient for your energy bills as less heat is needed for the same result. Underfloor systems have a lower operating temperature of around 40°C compared to a radiator at 65°C.

The installation process is simple, and you may even be able to fit it yourself if you choose the electric system. This way of heating your home also suits all floor coverings, so these systems tend to be the favoured heating method for those beginning a renovation project.

The system takes a little while to warm up, so timers can be used to ensure your room is at the perfect temperature when you need it. You can find more information and inspiration about underfloor heating online.


Is underfloor heating efficient?

Underfloor heating is energy efficient - up to 40% more than radiators. Due to the small size of your old radiators, they have to reach high temperatures to heat a room. The surface area is much more significant with underfloor heating and covers the whole room.

This means the temperature doesn't need to be as high to get the same warming effect. Having this system will drastically reduce your energy bills in the long run.

Does water underfloor heating pair better with a boiler or heat pump?

Underfloor heating doesn't need to reach high water temperatures and so is well suited to a heat pump. This ensures you can keep your heating off mains, although a pump must still be professionally installed. It works by taking in less energy than it outputs, which works well with underfloor heating because it can run at low temperatures.

Is underfloor heating worth it?

Underfloor heating can be expensive initially to install, depending on the system you choose and the size of the job. However, the energy efficiency of this kind of system will lower your running costs and reduce your energy bills quite considerably.

This makes it a good investment, and having a system like this installed can even increase the price of your property if you choose to sell. It frees up wall space and prevents the risk of children burning themselves on hot radiators. It also leaves no cold spots and heats your room evenly.

How long does it take to get underfloor heating installed?

You will typically need to factor in up to 2 days to prepare the floor. Depending on the size of the job, underfloor heating can be installed in 2-4 days. Installing the 'wet' underfloor heating can be more problematic than the 'dry' system.

You may need to dig up the floor or raise the bottom to accommodate the pipes beneath. Professionals can do this quickly, but it is worth considering when deciding which system to go for.