The ultimate underfloor heating guide

Underfloor heating: the epitome of luxury?

There’s nothing quite like the feeling of warmth under your feet on a chilly morning. Underfloor heating requires some effort and initial financial outlay, but it offers plenty of benefits in return. For a start, it’s energy-efficient and is a space-saving alternative to wall-mounted radiators. 

Read on to find out more about the different types of underfloor heating systems, their pros and cons, and how much it costs to install a new system in your home. 

How does underfloor heating work? 

Some systems use warm, piped-in water, while others use electric coils. But whether you go for dry or wet underfloor heating, it operates through the simple principle of heat waves rising through the air to warm the room. No matter the system, pipes or coils are usually placed on top of a separate layer of insulation to keep the heat moving upwards rather than spreading into the home’s foundation. Systems are connected to your boiler or mains supply of electricity, and a thermostat regulates temperature.  

What are the pros and cons of underfloor heating? 

There are plenty of reasons to give underfloor heating a try, but this type of system isn’t for everyone. Here are the main advantages of underfloor heating: 

  • Comfort and warmth – You’ll enjoy room-wide warmth in winter months with heated floors. It also makes walking around in bare feet, even on tiled or hardwood floors, far more comfortable. 

  • Increased home value – An efficient central heating system already boosts home value by 9%, according to some estimates. Underfloor heating not only ticks this box, but also adds a sense of luxury that homebuyers love. 

  • Increased efficiency – Speaking of an efficient heating system, underfloor heating distributes warmth evenly throughout the room. By comparison, a radiator can be patchy with its distribution. 

  • Better use of space – With no need for radiators in the room, you’ll have clean lines to work with and an increase in wall space. You’ll be able to fill these gaps with furnishings, kitchen units or storage. 

Of course, this type of system isn’t for everyone. Here are some of the drawbacks associated with underfloor heating: 

  • Messy installation – If you’re installing underfloor heating in an older home, you’ll experience some upheaval to your daily routine. Floors will need to be removed in order to install the coils or pipes, and the whole process can get messy. 

  • Initial cost – Although you’ll save money on your heating bills over time, you will be out of pocket for the initial installation. Electric underfloor heating systems can be a reasonably straightforward DIY project, but you’ll need to pay the professionals for water-based systems. 

  • Heating times – Underfloor heating is brilliant when it comes to heating the entire room evenly, but it does take a little longer for the whole room to warm up. Fortunately, systems come with a timer so you can set it to work when you need the heat most. 

Where to place underfloor heating in your home

You could install underfloor heating throughout the entire home, but many people will save it for ground-floor rooms, bathrooms and kitchens. It’s easiest to install at the same time as new flooring, which makes it a popular option for house extensions and conservatories. The type of flooring you have in each room also impacts whether or not it’s a good idea to install it. 

  • Hardwood flooring – Solid wood flooring is usually not compatible with underfloor heating, but engineered wooden boards are a good fit. These are crafted with multiple layers of wood, making them less prone to movement when exposed to changes in temperature or humidity. 

  • Carpeted flooring – If you already have thick carpeting, you may not notice the benefits of underfloor heating as much as you would with materials like tiles and laminate wood. However, underfloor heating is fully compatible if the carpet and underlay’s thermal resistance is below a 1.5 tog rating. 

  • Stones and tiles – Natural materials like slate and terracotta are quite popular in modern homes. Their thickness will determine whether or not underfloor heating is worthwhile – with thicker flagstones, it will take longer for the room to heat. 

Types of underfloor heating

There are two main types of underfloor heating systems, the first of which is electric. These operate using a network of wires placed under your floor. Some use heating mats to cover large areas of the floor space, while others will operate with an intricate network of individual wires. A layer of insulation sits underneath the wire network, keeping the generated heat moving upwards into the room. 

The other option is a water-based system, consisting of a network of pipes connected to the boiler. Installation is a bit trickier (and messier) with this type of system, and as a result, costs are usually higher since you’ll need to call in the plumber. However, wet underfloor heating systems are 30% more efficient than radiators, distributing heat evenly at a lower temperature. 

What does underfloor heating cost?

There are many factors that go into determining your underfloor heating cost, including the type of system you install, how many rooms you’re fitting, and the size of your home. For example, you could expect to pay approximately £5,000 for a wet underfloor heating system throughout a new build property. Room by room, wet systems cost about £20-£30 per square metre, not including the extensive fitting costs. 

Electric systems start at around £75 per square metre if you’re using mats, or £100 per square metre for individual wiring. You’ll need to add the cost of insulation materials as well as professional installation costs if you’re not doing it yourself. Electric systems are usually cheaper to install, but they can be up to 40% more expensive than wet underfloor heating systems in terms of operation. 

How to install underfloor heating systems 

As with underfloor heating costs, the type of system determines how it’s installed. You can opt to install electric systems yourself, but water-based systems are best handled by a qualified plumber. This is because the full installation process might require raising the floor to accommodate the pipes below.

For electric systems, choose from mats or loose wires to suit your floor space. In bathrooms or small rooms, mats will easily do the job and are quite easy to install. You simply lay them out across the smooth floor, with insulation placed above and below as needed. Loose wired systems can be distributed across larger floor spaces. Their primary benefit is flexibility, working with unusual shapes or layouts. In this case, it’s important to space the wires evenly or you’ll have some patches which are warmer than others. 

Wet systems are more complicated. You’ll need to install a network of pipes, connect these to your boiler, and potentially raise the flooring to fit everything in. Even with an electric system, it’s a good idea to hire a qualified electrician to connect the wires to your main supply. 

Tips to make the most of your system

No matter which type of system you choose, there are a few key differences between underfloor heating and radiators. Consider these tips to make the most of your system. 

  • Get the timing right – Heating a room takes longer with this type of system, though once the room’s been warmed it will stay comfortable despite any drafts. If you set the system on a timer to go off for a couple of hours in the early morning, your room will stay warm throughout the day. 

  • Place the controls in a convenient location – Anticipate controlling your system from a central location. Many of the latest models work with apps, allowing you to control each zone from your smartphone. Although each room will need its own valve, you can place these in a central cupboard for more convenient control purposes. 

  • Combine with insulation – Insulation and underfloor heating go hand in hand, as they work together to create a more energy-efficient home. Don’t skimp on insulation below your system, or the heat will radiate downwards and be less efficient. If you’re living in an older, single-glazed property, underfloor heating may not be enough to keep the home warm – you might wish to combine it with radiators or look to upgrade your windows. 

Bottom line

Although underfloor heating is more efficient than a radiator system, it’s still more of a luxury than a money-saving measure. According to the Energy Saving Trust, wet underfloor heating only saves £20 throughout the year – you’ll have to wait quite a while to make back the cost of installation. The greatest value for money comes with new-build homes or extensions, where you don’t have to remove existing flooring. 

Yet despite its costs, there are many benefits to underfloor heating. You’ll enjoy warmth beneath your feet, as well as a more evenly, efficiently heated room. While radiator heat dissipates when a window is opened, heated floors retain warmth for longer. It also offers a sleek, luxurious look within your home. Without radiators, you can maintain clean lines which is always a plus for those who enjoy minimalist interiors. 

Ben GallizziEnergy Expert - Oct 23rd 2019