Underfloor Heating Cost London 2026 | Wet vs Electric Price

Underfloor heating in London costs £60–£120 per square metre for electric systems and £120–£200 per square metre fitted for wet (water) systems in 2026. Electric is cheaper to install and ideal for retrofitting single rooms like bathrooms; wet systems cost more upfront but are far cheaper to run and suit whole floors, extensions and new screed. The right choice depends on the room, whether you are retrofitting or building new, and your floor height. This guide compares the two on installation cost, running cost and where each makes sense during a refurbishment.

How much does underfloor heating cost in London?

Underfloor heating splits into two systems with very different costs, and choosing between them is the first decision. Electric underfloor heating costs £60–£120 per square metre installed in 2026; wet, or water-based, underfloor heating costs £120–£200 per square metre fitted. Electric systems use a heating mat or cable laid under the floor finish and wired to a thermostat. They are thin, quick to install and well suited to single rooms. Wet systems circulate warm water through pipes laid in or on the floor, connected to the boiler or heat pump, and are more involved to install but much cheaper to run over a large area. The table below compares the two on fitted cost. The figures cover supply and installation but exclude floor finishes and, for wet systems, any boiler or manifold work; VAT applies to most of this work.

System / element	Typical London cost (2026)
Electric underfloor heating (per m²)	£60 – £120
Wet / water underfloor heating, fitted (per m²)	£120 – £200
Electric, typical bathroom (3–4 m²)	£250 – £450
Wet system, manifold and controls	£500 – £1,200

Electric versus wet underfloor heating

The electric-versus-wet decision comes down to area, running cost and floor build-up, and the right answer is usually different for a single bathroom than for a whole floor. Electric underfloor heating costs £60–£120 per square metre to install and is thin, typically adding only a few millimetres to the floor, so it retrofits easily under tile in a bathroom or kitchen without raising the floor noticeably. Its drawback is running cost: electricity is expensive per unit, so heating a large area with electric underfloor heating is costly to run, which is why it suits small rooms used in bursts rather than whole homes. Wet underfloor heating costs £120–£200 per square metre fitted because it involves laying pipework, connecting a manifold to the heating system, and usually a screed over the pipes. It runs at a low flow temperature, which makes it efficient and cheap to run over a large area, and it pairs especially well with a heat pump. The trade-off is a higher build-up and a more disruptive installation, which is why it is best designed in when a floor is already coming up. The rule of thumb is simple: electric for single rooms and retrofits, wet for whole floors, extensions and anywhere a new screed is going down anyway.

Factor	Electric	Wet (water)
Install cost per m²	£60 – £120	£120 – £200
Running cost	Higher	Lower
Floor build-up	Minimal (a few mm)	Higher (screed/pipes)
Best for	Single rooms, retrofit	Whole floors, extensions, new screed

Retrofit versus new screed installation

Whether you are retrofitting into an existing room or building a new floor changes both the cost and the sensible choice of system, so it is worth being clear which situation you are in. Retrofitting into an existing room, without taking the floor structure up, favours electric underfloor heating. The mat or cable is laid over the existing subfloor, often in a thin self-levelling layer, and tiled over, adding little height. This is the standard approach for adding warmth to a bathroom or kitchen during a refurbishment without major floor works, and it is why electric dominates single-room retrofits. New screed installation, where the floor is being built up anyway in an extension, a new bathroom or a full refurbishment, favours wet underfloor heating. The pipes are laid and a screed poured over them, so the heating becomes part of the floor build-up rather than an addition to it. Because the floor work is happening regardless, the incremental cost and disruption of the wet system is much lower than retrofitting it later. This is the central planning point: decide on underfloor heating before the floor goes down, because adding a wet system afterwards means taking the floor back up.

Which rooms benefit most from underfloor heating?

Underfloor heating is not equally worthwhile in every room, and concentrating it where it earns its keep is how you get the best value during a refurbishment. Bathrooms are the classic case: a warm tiled floor underfoot is a genuine comfort upgrade, the rooms are small so electric running costs stay modest, and the system frees up wall space otherwise taken by a radiator or towel rail. Kitchens benefit similarly, with the bonus that underfloor heating removes radiators from a room that is usually short of wall space. Extensions and open-plan spaces are ideal for wet underfloor heating: they are often built with a new screed, have large glazed areas that need even heat, and lack the wall runs for enough radiators. High-ceilinged living rooms and large areas used continuously suit wet systems, where the low running cost over a big footprint repays the higher install cost. Bedrooms are the weakest case for retrofit electric, since they are used mostly when warm bedding is already doing the job, though they are cheap to include in a wet system covering a whole floor. The practical message is to put electric where you want targeted comfort, and wet where you are heating a large or new area continuously.

Running costs: what underfloor heating costs to use

Installation is only half the story; running cost is where electric and wet systems diverge most, and it often decides which is the right long-term choice. Electric underfloor heating is cheap to install but expensive per unit of heat, because it converts electricity directly to warmth and electricity costs several times more per kilowatt-hour than gas. For a small bathroom used for an hour or two a day, that cost is modest and easily justified by the comfort. For a large area heated for long periods, electric running costs mount quickly, which is the main reason it is not recommended as a whole-home solution. Wet underfloor heating costs more to install but runs at a low flow temperature and draws its heat from the boiler or, better still, a heat pump, making it efficient and cheaper to run over a large area. Spread over a whole floor used daily, the lower running cost steadily repays the higher install cost. The honest summary is that electric wins on install cost and loses on running cost, so the more you will use it and the larger the area, the more a wet system makes financial sense. VAT applies to most of this work, and these running-cost differences should weigh as heavily as the install price when you choose.

When underfloor heating is worth it during a refurbishment

Underfloor heating is most worthwhile when the floor is already coming up, because that is when the disruptive part of the work, which dominates a retrofit, is happening anyway. During a refurbishment you are often relaying floors, replacing a bathroom, building an extension or pouring new screed. At those moments, adding underfloor heating is far cheaper and less disruptive than installing it as a standalone project later, because the floor preparation is shared. This is the single best reason to decide on underfloor heating early in a refurbishment rather than as an afterthought: a wet system added during the floor works costs a fraction of the same system retrofitted afterwards. The judgement, then, is one of timing and room choice. Put electric underfloor heating into bathrooms and kitchens being refitted, where the comfort gain is high and the area is small. Specify wet underfloor heating in extensions and whole floors being built up, where the running-cost saving over years repays the install cost. And decide before the floor goes down, not after, so the system is built into the floor rather than bolted on. Allow for VAT on top of the per-square-metre figures, and treat the choice as part of the wider heating and floor design rather than a late extra.

Frequently Asked Questions

How much does underfloor heating cost in London in 2026?

Electric underfloor heating costs £60–£120 per square metre installed, and wet (water) underfloor heating costs £120–£200 per square metre fitted. A typical bathroom electric system runs £250–£450, while a wet system also needs a manifold and controls at £500–£1,200. The figures cover supply and installation but exclude floor finishes, and VAT applies to most of this work.

Is wet or electric underfloor heating cheaper?

Electric is cheaper to install, at £60–£120 per square metre against £120–£200 for wet, but it is more expensive to run because electricity costs several times more per unit than gas. Wet systems cost more upfront but run at a low flow temperature and are far cheaper over a large area, especially with a heat pump. Electric is cheaper overall for single rooms used in bursts; wet is cheaper overall for whole floors used daily.

Can underfloor heating be retrofitted without raising the floor?

Electric underfloor heating can largely be retrofitted without a noticeable rise, as the mat or cable is only a few millimetres thick and is laid in a thin self-levelling layer under tile. This is why electric dominates single-room retrofits like bathrooms. Wet underfloor heating usually needs a higher build-up for pipes and screed, so it is best installed when the floor is being taken up or a new screed is going down anyway.

Which rooms are best for underfloor heating?

Bathrooms and kitchens are ideal for electric underfloor heating: the rooms are small so running costs stay modest, the warm floor is a real comfort upgrade, and it frees up wall space from radiators. Extensions, open-plan spaces and whole floors suit wet underfloor heating, where the low running cost over a large area repays the higher install cost. Bedrooms are the weakest case for standalone electric retrofit.

Is underfloor heating worth it during a refurbishment?

Yes, particularly when the floor is already coming up. Adding underfloor heating while you are relaying floors, refitting a bathroom or pouring a new screed is far cheaper and less disruptive than installing it later as a standalone job, because the floor preparation is shared. The key is to decide early: a wet system built into a new screed costs a fraction of the same system retrofitted after the floor is finished.

Underfloor Heating Cost in London: 2026 Price Guide