Devon & Cornwall 2026
How Much Does a Heat Pump Cost in Devon & Cornwall?
2026 installed prices, net cost after the £7,500 or £9,000 BUS grant, what drives the total up on older South West homes, and realistic planning bands — not brochure figures.
Quick Answer
How much does a heat pump cost? For a typical 3-bed in Devon or Cornwall in 2026, installed air source systems often sit around £10,000–£15,500 before grant. After the standard £7,500 BUS, many land about £4,000–£7,500 net.
Eligible oil/LPG replacements with no mains gas may use the £9,000 rate (about £1,500 less again — confirm live GOV.UK rules). Well-insulated homes with minimal radiator work sit lower; complex pipework, full emitter upgrades and awkward access sit higher.
Figures reviewed: August 2026 · Planning bands from public equipment prices plus professional install layer — how our numbers are built. Not a fixed quote.
Air source heat pump outdoor unit
Illustrative example of an air source heat pump outdoor unit — final siting, airflow, noise and access need a site check.
Typical Installed Costs Before Grant (2026)
These figures reflect what good local installers in the South West are currently quoting for a complete air source heat pump system (design, supply, installation and MCS commissioning).
| Property Type | Typical Cost (before grant) | Common Heat Pump Size | Notes |
|---|---|---|---|
| Small 2-bed / flat | £8,000 – £12,000 | 5–8 kW | Usually simpler installation |
| Average 3-bed house | £10,000 – £15,500 | 8–10 kW | Most common size in the region |
| Larger 4+ bed house | £13,500 – £19,000+ | 12–16 kW | More emitters and pipework |
| New build / extension | £9,000 – £13,500 | Varies | Usually lower due to easier access and new pipework |
Prices typically include the outdoor unit, indoor components, hot water cylinder, buffer or low-loss header where required, basic controls, design and MCS commissioning. They do not include major radiator upgrades or complete flow & return pipework replacement.
Net Cost After the BUS Grant
The Boiler Upgrade Scheme provides £7,500 towards an air source heat pump in most eligible cases. Where you are replacing oil or LPG and the property has no mains gas connection, a time-limited uplift takes the grant to £9,000 (from 21 July 2026, currently expected until 31 March 2027 — confirm on GOV.UK). This is deducted from the total cost.
Supply of full system after grant
On many standard 3-bed quotes the equipment package (heat pump, cylinder, buffer, controls and MCS) often reduces to roughly £1,500 – £3,500 after the grant is applied.
Installation labour
A straightforward install typically costs £2,500 – £3,500 (usually 2–3 days for a small team). This is paid on top of the equipment cost.
Realistic all-in net cost for most standard 3-bed houses in Devon & Cornwall on the £7,500 rate: about £4,000 – £7,500. Oil or LPG off-gas homes on the £9,000 rate often land £1,500 lower on the same install, all else equal.
It can drop lower on a well-insulated property with minimal emitter work (and further still on the oil/LPG £9,000 rate), and rise above £8,000–£10,000 if full radiator and pipework upgrades are required.
What Usually Pushes the Price Up in Devon & Cornwall
The base heat pump and cylinder are only part of the story. In older South West properties these are the items that most often increase the final figure:
Radiator upgrades
Many existing radiators are undersized for the lower flow temperatures of a heat pump. Good quality convective radiators typically cost £500 – £800 each supplied and installed. A full house upgrade can easily add several thousand pounds.
Existing small-bore pipework
A large number of older Devon and Cornwall homes still have 15mm or undersized 22mm pipework. At the lower flow temperatures used by heat pumps this often needs upgrading, which is one of the most common (and expensive) extras.
Long pipe runs and difficult access
Placing the outdoor unit a long way from the house (or in a restricted location) requires additional pre-insulated pipework and labour. Character properties and tight sites also increase installation time.
Poor existing insulation
The worse the insulation, the larger the heat pump needs to be. A well-insulated 150m² house might only need a 5–7 kW unit, while a poorly insulated one of the same size can require 10–12 kW or more — increasing both equipment and emitter costs.
What’s Usually Included vs What’s Extra
Almost always included
- Outdoor heat pump unit
- Hot water cylinder (correctly sized)
- Buffer tank or low-loss header (where required)
- Expansion vessel and basic controls
- Design, delivery and MCS commissioning
Frequently extra
- Radiator upgrades or replacements
- New flow & return pipework
- Quiet / premium outdoor unit options
- Advanced zoning or smart controls
- Significant insulation upgrades
A properly designed system should include a compatible hot water cylinder. Mixing components from different suppliers can create issues with the BUS grant application and long-term warranty.
Want a cost band for your property?
The free Planning Passport shows an indicative installed-cost range and size class for Devon & Cornwall homes — still not a fixed installer quote.
Start heat pump Passport →The Role of Insulation
Insulation is one of the most important factors affecting both the size of heat pump you need and your long-term running costs. We do not install insulation ourselves, but it is essential to understand its impact before you commit to a heat pump.
Why it matters so much
A heat pump works most efficiently when it can run at lower flow temperatures (typically 35–45°C). The better insulated your home is, the lower the heat loss, the smaller the heat pump can be, and the more efficiently it will run.
In practical terms, a well-insulated 150 m² house in Devon or Cornwall might only need a 5–7 kW heat pump. The same house with poor insulation could need 10–12 kW or more. That difference affects both the upfront cost and every electricity bill for the next 20 years.
What usually makes the biggest difference
- Loft insulation (cheap and high impact)
- Cavity wall insulation (where possible)
- Draught proofing around windows, doors and floors
- Underfloor insulation (especially on suspended timber floors)
Older Devon & Cornwall properties
Solid stone walls, small rooms and character features can limit internal insulation options. External wall insulation is sometimes possible but can affect appearance and planning. In many cases a combination of loft insulation, careful draught proofing and accepting a slightly larger heat pump is the most practical route.
New Build / Extension vs Full Retrofit
There is a significant cost difference between installing a heat pump in a new build or extension versus a full retrofit into an existing home.
In a new build the screed is already being laid to building control standards. Adding underfloor heating pipe at that stage is relatively inexpensive. In a retrofit you are usually working with overlay systems (XPS, gypsum boards or self-levelling compounds), which cost more in both materials and labour.
The same principle applies to the heat pump itself: new builds normally have better access, new pipework and higher insulation standards, all of which reduce both the size of the heat pump required and the complexity of the install.
Running Costs – Realistic Examples
heat pump running costs explained
A well-designed and properly commissioned air source heat pump in a reasonably insulated Devon or Cornwall home typically costs a similar amount to run as a modern gas boiler, and often less than an older oil or LPG system.
| Scenario (typical 3-bed) | Estimated Annual Running Cost | Notes |
|---|---|---|
| Well insulated + good SCOP (≈3.5–4.0) | £750 – £1,000 | Best case with heat-pump tariff |
| Average insulation + SCOP ≈3.0–3.3 | £950 – £1,300 | Most common real-world outcome |
| Poorer insulation or higher flow temps | £1,300 – £1,700+ | Can be higher than a good gas boiler |
What these figures assume
- Around 9,000–12,000 kWh of heat demand per year
- Current electricity unit rates
- A properly designed and commissioned system
The single biggest influence on running costs is not the brand of heat pump — it is the quality of the system design, the insulation level of the house, and how the system is controlled day-to-day.
Maintenance Costs
Heat pumps require an annual service to maintain efficiency and keep the manufacturer warranty valid.
Typical annual service
£150 – £220
Most common range charged by independent engineers in 2026
Compared to a gas boiler
Usually £50–£100 more per year than a standard boiler service, but heat pumps generally need fewer emergency repairs and have a longer expected lifespan (often 20+ years).
A proper service should include cleaning of the outdoor unit, refrigerant and electrical checks, filter cleaning, system pressure, and inspection of the hot water cylinder.
Common Mistakes That Increase Both Cost and Running Costs
See what size heat pump.
See radiator upgrades.
Oversizing the heat pump
A larger unit costs more to buy and can short-cycle, reducing efficiency and lifespan.
Keeping old undersized radiators
This forces higher flow temperatures and higher electricity use.
Constantly adjusting room thermostats
Heat pumps work best with steady, predictable demand. Frequent changes reduce SCOP.
Ignoring insulation first
Improving insulation reduces the size of heat pump required and lowers both capital and running costs.
Want a more accurate figure for your property?
Use our free Heat Pump Passport for a realistic indication of system size and cost, or tell us about your project and we will review it personally.
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Related Guides
Frequently asked questions
How much does a heat pump cost in the UK in 2026?
Fully installed air source systems commonly fall roughly £8,000–£19,000+ before grant depending on size and complexity. After BUS, many standard homes pay a mid-thousands net figure — see the tables on this page for Devon & Cornwall planning bands.
How much does a heat pump cost in Devon and Cornwall?
Typical net cost after the £7,500 grant for a standard 3-bed is often about £4,000–£7,500. Off-gas oil/LPG cases may access £9,000 where eligible. Rural access and older fabric can sit at the higher end.
Is the BUS grant £7,500 or £9,000?
Most eligible installs use £7,500. Many oil or LPG replacements with no mains gas may qualify for £9,000 in the published uplift window — always confirm current GOV.UK wording.
Does the price include new radiators?
Not always. Some quotes assume existing emitters; others include partial or full upgrades. Ask what is in and out of the figure. Radiator upgrades explained.
Is a heat pump cheaper to run than gas?
Often similar on a standard tariff with a good design — not automatically cheaper. Full comparison: heat pump vs gas running costs.
Public price evidence behind these figures
These Reality Checks show the public equipment prices that sit underneath the planning bands above.