Underfloor Heating Guide

What is Underfloor Heating?

Underfloor heating is the process of warming homes and offices through heating elements beneath the floor. With traces dating back to 5,000BC underfloor heating has been around for thousands of years and is becoming more and more popular as an alternative heating source for modern renovations. 

By 3,000BC there is evidence the Ancient Greeks & Romans were well versed on underfloor heating using a system called a Hypocaust allowed for hot air from pass underneath the building through a series of passages made possible by building homes on top of raised pillers or stilts. Hot air was made through an external fire hearth system that fed heat into the hypocaust.


Villa Armira, featuring a 'hypocaust' underfloor heating system. 

Different Types of Modern Underfloor Heating

Water Based Systems

Wet systems typically comprise of many hundred metres of piping being laid out on plastic fixtures before being covered by cement screed. Water-based systems are the most common choice whilst undertaking a major home overhaul (such as a rebuild) as the piping is laid down before subfloors are formed through screeding. Whilst this type tends to require more upfront initial costs, they will likely save you in the long run with bills. This would be best suited for those who believe they've found their 'forever home' or don't expect to be moving for the next 5 - 10 years.

Electrical Based Systems

Electrical systems used extremely thin thermal conducting pads that are laid out between the original subfloor and the floorcovering. Typically this system is best suited for DIY'ers or those who want underfloor heating without ripping up the concrete subfloor to lay out a water-based system. An electrical-based system will typically have cheaper up-front costings, but may end up being more expensive in the long run with bills. This would be best suited for short-term homes where you're still on your journey finding that forever home and would consider moving within 5 years for example. 

The benefits of Underfloor Heating

Believe it or not but underfloor heating can replace your conventional heating system, particularly with a water-based system. This means you can completely do away with any radiators and have a much cleaner interior. Whats more, with modern home thermostat technology you can also connect your underfloor heating controller to your home thermostat (if smart-enabled) and so you'll be able to schedule routines, home and away, eco modes and much more. These benefits also apply to some electrical-based systems as well.

You'll also be able to reduce heating bills too (particularly with a water-based system) as it can retain it's heat for some time, rather than radiators that begin to cool immediately after being switched off. A quick hour or two in the early hours of the morning will usually be more than enough to stay comfortable for the day. 

All these benefits come through the way in which the heat enters your home. As we all know, heat rise, so by the heat entering from below you'll feel the atmospheric heat increase from below and will cool as it rises to the top. Conventional radiators however have a tendency to reach very high temperatures immediately which ends up rising quickly and heating the upper section of the room before the rest of the room acclimatises.

What to look for when picking a floorcovering with underfloor heating

Always refer to your user guide provided by the manufacturer of your underfloor heating system for their exact advice, though as a general rule all systems will state a max TOG value you should not surpass with your chosen floorcoverings to ensure optimum performance. Typically this value is around 2.50 TOG. The lower you can keep your overall TOG value the better heat transfer you will have through your flooring, making your system work more efficiently. No matter your chosen flooring, if it requires an underlay there are plenty of underlays we would recommend using to keep that TOG value as low as possible, so you can then leave plenty of TOG breathing room to use when deciding on your actual flooring. 

Our recommended floors best used with underfloor heating

Whilst it may seem as long as you sit inside the max TOG parameters any floorcovering will work with underfloor heating, and this is true, there will however be some that work better than others from an efficiency perspective. Hard floors installed with the help of adhesives (a.k.a 'dryback' or 'fully bonded' methods) will be your best bet for optimum efficiency. This is because hard floors installed with glue (suitable for high temperature locations of course) do not require an underlay and by removing the underlay out of the installation this is one less layer for the heat to transfer through, giving you greater efficiency. 

Further Reading

We hope that our quick guide on underfloor heating has provided insight on best practices when weighing up options for your new floor however if you find you still have some questions please do not hesitate to contact our team of flooring experts who will be happy to assist. If not, why not take a look over our product Buying Guides?