Expert Advice on Underfloor Heating Boiler Requirements

Underfloor heating (UFH) is an excellent way of heating your home as an alternative to traditional central heating options. However, you need to make sure that your boiler meets the requirements for underfloor heating in your home.

This guide will give you comprehensive boiler advice on underfloor heating to ensure you make the right choice for your home.

What are the main underfloor heating boiler requirements?

Underfloor heating systems work exceptionally well with a variety of boiler types. Wet underfloor heating systems are great for all types of heating sources as they can work with anything from your usual boiler system to newer sustainable technologies, such as solar thermal energy or heat pumps.

Electric underfloor heating systems - also known as dry underfloor heating - work well with various boiler types, including combi, system, conventional gas boilers, oil boilers, LPG boilers, and condensing boilers.

A considerable advantage to installing underfloor heating is the ability to upgrade your current boiler system. Boilers are responsible for more than half of our energy bills, so cutting those costs could save you money in the long run. You could replace your older gas boiler with a highly efficient condensing boiler, saving money and cutting emissions.

What kind of boiler do you need for underfloor heating?

You do not need a specific kind of underfloor heating boiler for your UFH to work. However, some boilers and heating systems work better with underfloor heating systems than others.

Gas combi boilers

Gas combination boilers will require some minor adjustments to your heating system to ensure they work to their full potential. A certified gas heating engineer should be able to help you prepare your system to be able to accommodate an underfloor heating system.

You will need to have a two-port valve installed if your central heating system and UFH run from the same boiler to enable the boiler to run the systems separately. This valve will help to control the flow of water into and from the boiler to other areas of the central heating system around your home. Without it, the boiler could overheat if it runs the UFH and radiators simultaneously, causing it to go into error mode.

Condensing boilers

A condensing boiler is another excellent option for underfloor heating as they recover as much waste heat as they can.

They then reuse waste heat in the system, which would otherwise be put out into the atmosphere from the flue.

Unfortunately, most standard radiators do not work as well with condensing boilers as they cannot make the most of the available energy. Traditional radiators have a flow temperature of 70°C and output of 60°C, which is above the range of a condensing boiler which operates at around 53°C.

As underfloor heating systems have a flow temperature of 50°C and an output of 40°C, they are ideally suited to this type of boiler.

Heat pumps

You could also consider installing air source heat pumps as another alternative to a boiler. A heat pump works by extracting heat from air outside into your home, heating it to a better temperature. Heat pumps are incredibly efficient and work exceptionally well with UFH.

It is worth remembering that heat pumps have lower outputs than a boiler would, meaning your water might not be as hot as it used to be. While this makes them ideal for underfloor heating, if you have radiators, you may need to replace them with bigger ones to ensure each room is evenly heated.

What is the right boiler size for underfloor heating?

The right underfloor heating boiler size depends on a few factors, including the heat output that your UFH requires and whether you have home insulation. All boilers have different flow temperatures and output temperatures, so you want to make sure your boiler's capacity matches the flow and output of your underfloor heating.

Our comprehensive boiler buying guide will help you choose the best boiler for your underfloor heating needs.

Underfloor heating and boilers FAQs

Do you need a special boiler for underfloor heating?

No, you do not need a special boiler for underfloor heating. Most UFH systems work brilliantly with all types of boilers, including gas combi boilers, condensing boilers and oil boilers. However, your current boiler may need some adjustments to ensure it works efficiently with the new underfloor heating.

Is underfloor heating right for me?

Underfloor heating is an excellent option for warming up your home and is suitable for many different properties. Whether you are renovating your home or considering building a new house, installing underfloor heating can improve the heating controls in your home. UFH heats a large surface area and can, alongside insulation, reduce heat loss.

Can you run underfloor heating off a boiler?

Yes, you can! Wet underfloor heating works with several different types of boilers, meaning it can be installed in most homes. It works with some boilers better than others, such as condensing boilers.

If you install dry or electric underfloor heating, it will not need to run from the boiler. Electric UFH is instead powered by cables or mats connected to your electricity.

What size combi boiler do I need for underfloor heating?

Most sizes of combi boilers will work with underfloor heating systems as long as certain adjustments are made. You will need a certified heating engineer to fit a two-port valve to your boiler to allow it to run your underfloor heating and radiators separately without overheating.

How do I use an underfloor heating thermostat?

Thermostats for underfloor heating work in the same way that a standard thermostat does, so they are easy to use. You could choose a more traditional style thermostat or opt for a smart thermostat to improve your heating controls.

Smart heating controls allow you to adjust your heating from wherever you are and can be controlled using a mobile or tablet device.

Do I still need radiators if I have underfloor heating?

You do not need to have radiators in a room with underfloor heating, but there is nothing to say you cannot keep both. Most people choose to install UFH as an alternative during renovations or build projects as it generates radiant heat to evenly warm a room. However, you can always keep your original radiators in the room and turn them off. Then if you ever need to provide an additional heating boost, you always have the option to use it.

Some people may choose to replace their radiators with underfloor heating completely. However, if you decide to do this, you will need to work out the potential heat loss calculations. These calculations will show you whether the heat output from UFH will match the depends on a certain space.

Underfloor heating (UFH) is a great way of heating your home as an alternative to traditional central heating options. However, you need to make sure that you get the right boiler and underfloor heating option for your home. This article will give you comprehensive boiler advice on underfloor heating to ensure you make the right choice for your home.