Underfloor Heating Cornwall

Wet vs electric underfloor heating: which is right?

There are two kinds of underfloor heating, and choosing correctly matters more than any other decision. Wet (water-based, or hydronic) UFH circulates warm water through a network of pipes laid beneath the floor, fed by your boiler or — ideally — a heat pump. It costs more to install but runs at a fraction of the price and is the only sensible choice for whole rooms and for the whole ground floor. Electric (dry) UFH is a heating mat or cable that warms the floor directly from the mains. It is cheap and quick to fit, which makes it perfect under a bathroom or en-suite floor, but running it as primary heating for a living room is expensive because you are paying full electricity rates for every unit of heat.

Our honest rule of thumb: wet UFH for whole rooms and heat-pump homes, electric UFH only for small wet-room floors. Because we fit both, we have no reason to push you toward one — we specify whichever genuinely suits each space at survey.

How much does underfloor heating cost in Cornwall?

The most useful number is cost per square metre, because it scales with your actual floor area. The table below shows typical CCS installed ranges in Cornwall for each system type, including 0% VAT where the work is part of a heat pump project. Final cost depends on floor build-up, room layout and floor finish.

As a guide, a typical ground floor in a 3-bed Cornwall home (50-60 m²) comes in at around £4,000-£7,000 for a wet system. Every quote is built from a room-by-room heat-loss calculation to BS EN 12831 — not a flat per-m² figure — so the output and running-cost estimates on your quote reflect your actual property. For the underlying technical detail and the brands we fit, see our underfloor heating service page, and to talk numbers for your rooms, book a free survey.

Floor build-up by floor type: height and response

The right method depends entirely on what is under your existing floor. This is where retrofit projects succeed or fail, so we survey the build-up before quoting. The table below shows the three common Cornwall scenarios, the height each adds, and how quickly each responds to the thermostat.

The practical takeaway: a new screed floor is the most efficient but needs planned height and continuous running, while suspended-timber and slim-overlay systems add almost no height and respond quickly, which is why they dominate Cornwall retrofits. We set weather-compensated controls to suit whichever build-up you have, so a high-mass screed never feels sluggish and a low-mass overlay never overshoots.

The underfloor heating + heat pump partnership

This is the genuinely important part, and it is where a Cornwall installer that does both heat pumps and UFH adds real value. A heat pump is at its most efficient when it produces heat at a low flow temperature. Radiators typically demand 55-65°C; underfloor heating is happy at just 30-45°C because it uses the whole floor as a large, gentle emitter. Every 1°C you take off the flow temperature improves efficiency by roughly 2%.

The result compounds. A heat pump feeding underfloor heating routinely achieves a seasonal efficiency (SCOP) of 3.5-4.0 — delivering useful heat at around 6-7p/kWh at current electricity prices — whereas the same heat pump forced to run hot radiators drops to a SCOP of 2.5-3.0. In real terms that is about 40% lower heating running costs for the low-temperature UFH system. It is also more comfortable: even, draught-free warmth with no cold spots and no bulky radiators on the walls.

Because we are Gas Safe registered and MCS certified, when you pair the two we design the low-temperature system, size the heat pump, install the UFH and handle the commissioning as one job — and the heat-pump element attracts the up-to-£9,000 Boiler Upgrade Scheme grant, which we apply for on your behalf. See our heat pump installation page for the pump side, and our renewable heating in Cornwall hub for how UFH, heat pumps, cylinders and controls fit together as a whole low-carbon system.

Is underfloor heating cheaper to run than radiators?

It depends entirely on what is producing the heat. Underfloor heating covers the whole floor area, so it delivers the same warmth at a lower water temperature than radiators — and that lower flow temperature is what makes it cheaper to run with a heat pump. A heat pump's efficiency rises as the flow temperature falls, so the same house heated to the same comfort costs less to run through a floor at 35-40°C than through radiators at 45-55°C.

With a gas or oil boiler the picture is different: the boiler burns fuel at the same efficiency either way, so a wet underfloor system saves little on running cost and is chosen for comfort, even heat and clear walls instead. Electric underfloor heating is the most expensive per unit of heat, because it converts electricity to heat one-for-one with no multiplication — which is why we fit it in single rooms rather than whole houses.

The downsides and the common problems

The honest list, before you commit:

• Response time. A screed floor is a heat battery: it takes hours to warm and hours to cool. That suits a house held at a steady temperature and frustrates anyone used to a quick blast of heat.
• Floor height. Retrofitting into an existing room costs height — from around 15-25mm for a low-profile overlay to 65-75mm for a full screed, which affects door thresholds and stair risers.
• Floor coverings matter. Tile and stone transmit heat best. Thick carpet and underlay act as insulation, and some engineered timber has a maximum surface temperature — check the manufacturer's limit before buying the floor.
• Getting at a fault. Pipework is buried, so leaks are rare but disruptive. Continuous loops with no buried joints, and a pressure test before the screed goes down, are what prevent the disruptive case.
• Control errors are the usual complaint. Most "underfloor heating does not work" calls are zoning and setback problems — a floor turned off overnight that cannot recover by breakfast, or a room thermostat fighting a weather compensation curve.

Zoning and controls, the part that decides comfort

A manifold gives each loop its own actuator, so rooms can be zoned individually. With a heat pump the aim is steady, low-temperature operation: weather compensation setting the flow temperature from outside conditions, long run times, and shallow setbacks rather than deep on-off schedules. Zoning too aggressively is the classic mistake — closing most loops leaves the heat pump with nowhere to put its output and forces it to cycle, which costs efficiency.

Grants when underfloor heating comes with a heat pump

Underfloor heating on its own has no grant. Paired with a heat pump it sits inside a funded project: the Boiler Upgrade Scheme pays £7,500 towards an air source or ground source heat pump, rising to £9,000 until March 2027 where you are replacing oil or LPG and have no mains gas connection. Heat pump installations in homes are zero-rated for VAT until 31 March 2027. The grant is a fixed amount towards the heat pump, not a separate payment for the floor — see our Boiler Upgrade Scheme Cornwall page, or heat pumps Cornwall for how the two are designed together.

Underfloor heating in Cornwall homes: granite, period and new-build

Cornwall's housing stock is unusually varied, and underfloor heating suits both ends of it. In new builds and extensions — from developments around Truro, Newquay and St Austell to self-build plots across the county — a screed UFH system is designed in from the start, giving the lowest running costs and a completely clear-walled interior. This is increasingly the default as new homes move to heat pumps and away from gas.

At the other end, Cornwall has a huge number of granite, cob, stone and period cottages — the kind of solid-wall, hard-to-heat homes found around Redruth, Camborne, the mining villages and the coast. These are exactly the properties where retrofit underfloor heating, paired with a high-flow-temperature heat pump where needed, transforms comfort. Solid stone floors take a slim overlay; suspended timber floors take spreader plates from below with no loss of height. We are used to working sympathetically in older Cornish properties, including where floors are uneven or heritage-sensitive. For the far west — listed buildings on Chapel Street and granite cottages in Newlyn and Mousehole — see underfloor heating Penzance.

Retrofit considerations for existing floors

Retrofit is entirely achievable in most Cornwall homes, but it rewards proper survey work. The things we check first: floor build-up and existing height (to protect door, stair and threshold clearances); insulation beneath the floor, since UFH into an uninsulated floor loses heat downward; the floor finish you want (tile and stone conduct heat best; engineered wood and LVT are fine; deep-pile carpet with thick underlay is the one to avoid); and whether a downstairs-UFH, upstairs-radiators hybrid on one low-temperature circuit is the least disruptive route. We also confirm your heat source can run at the low flow temperature UFH needs — and if you are still on an old boiler, we will lay out the heat-pump option honestly rather than assume it.

There is one thing we will not do: over-promise a grant. Underfloor heating on its own has no dedicated grant. The genuine savings are 0% VAT (to 31 March 2027) on the wider heating works and the £7,500 heat-pump grant when UFH is part of a heat pump install. There is no FETF or farm-specific grant for domestic UFH, and we will only ever quote what actually applies to your project.