How Does Underfloor Heating Work?

Underfloor heating is a highly efficient and environmentally-friendly way to heat your home. With UFH your rooms are heated from the floor up to the ceiling providing an even, ambient temperature that can be thermostatically controlled. Radiators, on the other hand, push heat outwards, leaving areas that are furthest from the radiator, much cooler. Here we explain in detail how underfloor heating works so you can get a better understanding.

Types of underfloor heating systems

Basically, there are 2 types of underfloor heating systems, which are electric and water. The principle for both is exactly the same in that heat is generated and then rises up through the floor. However, the mechanics of how they work and the components required to make them work are very different.

Electric underfloor heating

Electric underfloor heating is a system that sends heat up through the floors of your rooms. It comprises a series of heating mats, which consist of a single electric cable that is laid flat and looped over the mat to which it is attached. UFH mats are ideal for laying under both large open space areas and smaller spaces. Loose cable is also available for laying under irregular shaped spaces.

Water underfloor heating

A water underfloor heating system or a ‘wet’ system is much more complex than an electric UFH system. Instead of cables, this system relies on a series of pipes, in which hot water is pumped. This system is preferred for new builds as the installation process can be very disruptive. It’s also more expensive to install than electric but costs less to run.

Key system components

An electric underfloor heating system consists of electric cables and mats, which are connected to your electricity supply and controlled by a thermostat. Water-based UFH systems comprise water pipes, a pump and a thermostat. This system needs to work with an existing central heating system and boiler or with an air pump.

Thermostats

One of the essential controls for underfloor heating is the thermostat. Thermostats are used for regulating the internal temperature of your home regardless of the type of UFH system you have installed. Smart thermostats use Wi-Fi for home automation and can be controlled by a phone, smart speaker or tablet over an Internet connection. Thermostats are available for both electric UFH and water UFH systems.

Wiring centre

With a water underfloor heating system, there will inevitably be connecting wires from each heating zone, separately controlled by a single thermostat. State-of-the-art wiring centres allow all the wiring of the UFH system, including the actuator, boiler and pump connections, to be wired from a single convenient point.

Underfloor heating control pack and manifold

A control pack and manifold allows you to effectively manage the flow rate, temperature and pressure of the water that is pumped through the heating system. Underfloor heating manifolds enable you to control multiple zones at the same time, giving you complete control over the temperature of each zone or room.

Pipe circuits

A water-based underfloor heating system relies heavily on high-quality pipe circuits. Underfloor heating pipes need to be corrosion-resistant and able to withstand high pressure and high temperatures while remaining flexible and durable. Best quality pipes carry a 50-year guarantee.

How does electric underfloor heating work?

With underfloor heating controls explained, let’s now look at how the electric UFH heating system works. Basically, it involves a series of mats, which comprises insulated electric cables. Electric underfloor heating, also known as a ‘dry’ UFH system, can be laid under wooden floorboards, linoleum and vinyl floor surfaces and carpets.

They can also be installed beneath stone and tiled floors. A foil mat option is available for laying under laminate flooring. They are relatively quick and easy to install and not beyond the capability of the DIY enthusiast, although a qualified electrician will be required to install a thermostat.

How does water underfloor heating work?

A water underfloor heating system works with your existing central heating system, or with a heat pump, as shown in the underfloor heating diagram. With an existing gas or electric boiler and pump, hot water is pumped through the underfloor pipes much, in the same way, it would be pumped through radiators.

A heat pump uses ambient air, which is compressed to increase the pressure and temperature. This heat is then transferred via a heat exchanger so that it can heat your water. The heated water is then pumped through the UFH system. Water underfloor heating systems can be difficult to install in existing homes and are best suited to new-build properties.

Which flooring materials can be used with underfloor heating systems?

The best types of flooring materials to use with UFH systems are stone or ceramic tiles. This is because these materials are thermally conductive, providing efficient heat transfer to the floor surface. Engineered wood such as composite or manufactured board is also an effective material for heat transfer.

Polished screed and resin floor surfaces offer high heat transfer levels along with vinyl and linoleum. Carpets and rugs are less conductive as they tend to insulate. Laminate is a good option for use with underfloor heating systems but is subject to a maximum UFH temperature of 27°C.

Conclusion

Both electric and water-based underfloor heating systems are environmentally-friendly options and over time, will save you money on your energy bills. Electric underfloor heating is quicker and easier to install into existing properties but the running costs are generally higher than water-based UFH systems. However, DIY kits are available, which could amount to significant savings in installation costs.

Water underfloor heating is better suited to new-build properties as the installation process can be quite disruptive. Installation costs are much higher than electric UFH systems due to the number of components needed and the amount of labour time involved. More information and advice can be found on our website here, The Underfloor Heating Store.