Underfloor heating cost: what affects the price

Why the price varies so much

Underfloor heating isn't a single product with a single price. It's a system designed around a room — its size, what the floor is made of, how well it's insulated and what's going on top. Two kitchens of the same size can end up very different jobs.

The biggest decisions are which type of system you choose and whether the floor is being built from scratch or the heating is going on top of an existing one.

Wet (water) vs electric systems

A wet system runs warm water from your boiler through pipes in the floor. It costs more to install, because it needs pipework, a manifold, a mixing unit and connection to the boiler, but it's usually cheaper to run on gas and suits larger areas and whole floors.

An electric system uses heating mats or cables under the floor finish. It's simpler and quicker to fit, so it's often used in small rooms like bathrooms or en-suites, but running costs are generally higher because it uses electricity. Our underfloor heating service is focused on wet systems connected to your heating.

Room size and number of zones

More floor area means more pipe, more insulation and more labour. The number of zones matters too: each zone — typically a room — has its own loop or loops on the manifold and its own thermostat. Heating one open-plan kitchen is one zone; doing a whole ground floor might be four or five, each needing controls.

Screed or overlay

In new floors, such as an extension, the pipes are laid on insulation and covered with a layer of screed. This holds heat well and gives an even warmth, and it's usually the most cost-effective way to do a wet system because the floor is being built anyway. The screed does need time to dry before the final floor goes down.

In existing rooms, digging up a solid floor to fit a screed system is a big job. Low-profile overlay boards sit on top of the existing floor instead. They raise the floor less than a full screed, but the boards cost more per square metre and may mean adjusting door thresholds and skirting.

Insulation

Underfloor heating needs good insulation underneath, or a lot of the heat goes down into the ground instead of up into the room. In a new extension, insulation is part of the build. In older homes with little or no floor insulation, adding it may be part of the cost, and it makes a real difference to how well the system performs.

Floor coverings

Tiles and stone conduct heat well and are ideal. Engineered wood, laminate, vinyl and carpet can all work, but each has a maximum floor temperature and some resist heat more than others. A thick carpet with a heavy underlay can make the system slow to respond. Check the covering is suitable for underfloor heating before you buy it.

Connecting to the boiler and controls

A wet system has to work with your boiler and the rest of your heating. That means a mixing unit to keep the floor water at a lower temperature than radiators, a manifold, a pump and a wiring centre to link the thermostats. If radiators remain in other rooms, the controls must manage both. Your boiler's output needs to be enough for the extra load. These parts of the job are where good central heating knowledge matters.

Renovation vs new extension: timing

The cheapest time to add underfloor heating is when a floor is being laid anyway. If you're planning an extension or a big kitchen renovation, bring it up at the design stage so floor heights, insulation and screed depth can be planned together. Fitting it into a finished room later is always more disruptive.

In a bathroom refit, underfloor heating can be planned alongside the new suite — see our bathroom installations page. Whatever the project, contact us early with drawings or photos and we'll talk you through the options and give you a free quote.