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Heat Pumps Guide UK: Types, Costs, Grants and Suitability
Heat pumps have moved from niche technology to mainstream heating solution in the UK. Backed by government grants worth up to £7,500, rising gas prices and tightening building regulations, they are now the leading low-carbon replacement for gas and oil boilers. This guide covers everything a UK homeowner needs to know before making the switch.
How Heat Pumps Work
A heat pump moves heat from one place to another rather than generating it by burning fuel. It works on the same principle as a refrigerator but in reverse: a refrigerant absorbs low-grade heat from the air or ground, a compressor raises its temperature, and a heat exchanger releases that warmth into your central heating and hot water system.
Because the heat pump is transferring existing energy rather than creating it from scratch, it can deliver significantly more heat energy than the electrical energy it consumes. This ratio is measured as the Coefficient of Performance (COP).
Types of Heat Pump
Air Source Heat Pumps (ASHP)
Air source heat pumps are by far the most common type installed in UK homes. An outdoor unit — roughly the size of a large suitcase — draws heat from the outside air. Modern ASHPs continue to work efficiently at temperatures as low as minus 15 degrees Celsius, making them well suited to the British climate.
Typical installation cost: £8,000 to £14,000 before grants Space required: around one square metre of outdoor space with adequate airflow Best for: most UK homes, especially those without large gardens
Ground Source Heat Pumps (GSHP)
Ground source heat pumps extract heat from the ground via a loop of pipes buried either horizontally in trenches or vertically in boreholes. Because ground temperature remains stable at around 10 to 12 degrees Celsius year-round, GSHPs tend to be more efficient than ASHPs, particularly in winter.
Typical installation cost: £15,000 to £35,000 before grants Space required: a garden large enough for horizontal trenches (roughly equivalent to the floor area of the property) or access for a borehole rig Best for: rural properties with ample land, new builds, and homes off the gas grid
Hybrid Heat Pumps
A hybrid system pairs an air source heat pump with an existing gas or oil boiler. The heat pump handles most of the heating load, and the boiler kicks in only during the coldest spells or to top up hot water demand. This approach can suit older, less well-insulated homes where a full heat pump system might struggle to maintain comfortable temperatures during peak winter.
Typical installation cost: £5,000 to £10,000 on top of an existing boiler Best for: homes that are not yet ready for full electrification, or where insulation upgrades are planned for a later date
Air-to-Air Heat Pumps
Air-to-air systems deliver warm air directly into rooms via wall-mounted or ceiling-mounted units, similar to air conditioning. They cannot heat water, so they are not a complete replacement for a boiler. They are common in commercial settings but less popular for UK domestic use. Note that air-to-air systems are not currently eligible for the Boiler Upgrade Scheme.
Installation Costs
The total cost of installing a heat pump depends on the type of system, the size of your property, whether your existing radiators and pipework are compatible, and the complexity of the installation.
| System | Typical cost (before grant) | After BUS grant |
|---|---|---|
| Air source heat pump | £8,000 – £14,000 | £500 – £6,500 |
| Ground source heat pump | £15,000 – £35,000 | £7,500 – £27,500 |
| Hybrid heat pump | £5,000 – £10,000 | Not currently eligible |
Additional costs may include upgrading radiators to larger models, adding underfloor heating, improving insulation, or upgrading the hot water cylinder. A thorough home survey by an MCS-certified installer will identify exactly what is needed.
For a detailed breakdown of what drives installation costs, read our full article on heat pump installation costs in the UK.
Heat Pump vs Gas Boiler
The question most homeowners ask first is whether a heat pump is worth the extra expense compared with simply replacing their gas boiler. The answer depends on your priorities: upfront cost, long-term running costs, carbon footprint and future-proofing.
| Factor | Heat pump | Gas boiler |
|---|---|---|
| Upfront cost (after grant) | £500 – £6,500 | £2,000 – £4,000 |
| Annual running cost | £400 – £700 | £550 – £900 |
| Lifespan | 20 – 25 years | 10 – 15 years |
| Carbon emissions | Very low | Moderate to high |
| Future gas boiler ban risk | None | High (2035 target) |
Gas boiler replacements will become increasingly restricted as the UK moves towards its 2035 phase-out target for new fossil fuel heating in homes. Installing a heat pump now avoids a forced switch later, often at a less convenient time.
We cover the full cost comparison — including ten-year total cost of ownership — in our article on heat pump vs gas boiler costs in 2026.
Pros and Cons
Advantages
- Lower running costs — a well-installed heat pump in an efficient home can cut heating bills by 20 to 40 percent compared with a gas boiler.
- Dramatically lower carbon emissions — heat pumps produce no direct emissions at the point of use and benefit from the ongoing decarbonisation of the electricity grid.
- Long lifespan — heat pumps typically last 20 to 25 years, roughly double the lifespan of a gas boiler.
- Cooling capability — many air source heat pumps can reverse their cycle to provide cooling in summer.
- Generous grants available — the Boiler Upgrade Scheme can cover a substantial portion of the upfront cost.
Disadvantages
- Higher upfront cost — even after grants, heat pumps cost more to install than a like-for-like boiler replacement.
- Home preparation may be needed — older homes may need improved insulation or larger radiators to get the best performance.
- Outdoor unit noise — ASHPs produce a low hum (typically 40 to 50 decibels at one metre), which needs to be considered in relation to neighbouring properties.
- Lower flow temperatures — heat pumps work most efficiently at lower water temperatures (35 to 45 degrees Celsius), which may require adjustments to your heating system.
- Electricity dependency — running costs are tied to electricity prices, which per kWh are higher than gas, although the heat pump's efficiency more than compensates.
For a deeper dive, see our article on the pros and cons of heat pumps vs boilers.
Government Grants for Heat Pumps
The Boiler Upgrade Scheme (BUS) is the main government grant for heat pump installations in England and Wales. As of 2026, it offers:
- £7,500 towards an air source heat pump
- £7,500 towards a ground source heat pump
Eligibility
To qualify for the BUS grant you must:
- Own the property (landlords and owner-occupiers are eligible; new builds are not).
- Have a valid Energy Performance Certificate (EPC) with no outstanding recommendations for loft or cavity wall insulation — or have those insulation measures already in place.
- Use an MCS-certified installer who will apply for the grant on your behalf.
- Be replacing an existing fossil fuel heating system (gas, oil or LPG boiler, or electric storage heaters).
Additional support may be available through the ECO4 scheme and local authority programmes, particularly for low-income households.
Our dedicated article on heat pump installation grants in 2026 walks through the application process step by step.
Which Homes Are Suitable?
Heat pumps can work in most UK homes, but some properties are better suited than others. The key factors are insulation, available space and the existing heating distribution system.
Insulation
Heat pumps operate at lower flow temperatures than gas boilers, so your home needs to retain heat well. Properties with an EPC rating of D or above are generally good candidates. If your home is poorly insulated, upgrading your loft insulation and cavity or solid wall insulation before or alongside the heat pump installation will improve both comfort and efficiency.
Space
An ASHP needs roughly one square metre of clear outdoor space, at least 30 centimetres away from walls, with unrestricted airflow. A GSHP requires considerably more garden space for ground loops — typically an area equivalent to the property's footprint — or a borehole.
Heating Distribution
Heat pumps perform best with larger radiators or underfloor heating, which operate efficiently at lower water temperatures. If your home already has underfloor heating, it is an ideal match. Standard radiators can work, but an installer may recommend upsizing some panels in key rooms.
Property Types at a Glance
| Property type | Suitability | Notes |
|---|---|---|
| Detached house | Excellent | Space for outdoor unit and usually good scope for insulation |
| Semi-detached | Good | Check proximity to neighbouring property for noise |
| Terraced house | Moderate | Rear access needed; may have limited outdoor space |
| Flat / apartment | Limited | Shared access and planning considerations; ASHP may need freeholder consent |
| Listed building | Case by case | Planning restrictions may apply; GSHP with boreholes may be an option |
| New build | Excellent | Most new builds from 2025 must meet the Future Homes Standard |
COP and SCOP Explained
The Coefficient of Performance (COP) tells you how much heat a heat pump delivers for each unit of electricity it uses. A COP of 3.0 means the system produces three kilowatt-hours of heat for every one kilowatt-hour of electricity consumed.
COP varies with conditions — it is higher in mild weather and lower when the outside temperature drops. That is why the more useful figure for comparing systems is the Seasonal Coefficient of Performance (SCOP), which averages efficiency across an entire heating season.
What SCOP Numbers to Expect
- Air source heat pump: SCOP of 2.5 to 3.5 (meaning 250 to 350 percent efficient across the year)
- Ground source heat pump: SCOP of 3.0 to 4.5
By comparison, a modern condensing gas boiler operates at roughly 90 to 94 percent efficiency. Even a modest ASHP with an SCOP of 2.8 is roughly three times more efficient than a gas boiler.
When comparing quotes, always ask installers for the predicted SCOP rather than the peak COP, as this gives a far more realistic picture of real-world performance.
Planning Permission and Noise
Permitted Development
Most domestic air source heat pump installations fall under permitted development rights, meaning you do not need to apply for planning permission, provided you meet these conditions:
- The unit is at least one metre from the property boundary.
- Only one ASHP is installed on the property.
- It is not installed on a pitched roof, a wall or roof fronting a highway, or on a building within the curtilage of a listed building.
- The installation complies with the MCS planning standards, including noise limits.
Ground source heat pumps using horizontal trenches almost always qualify under permitted development. Borehole installations may need additional checks depending on the local authority.
If you live in a conservation area, national park, Area of Outstanding Natural Beauty, or the Broads, additional restrictions apply and you should check with your local planning department before proceeding.
Noise
Modern ASHPs are designed to be quiet. Most models produce between 40 and 50 decibels at one metre — comparable to a quiet conversation or a household refrigerator. At the property boundary, this typically drops to 30 to 35 decibels, well within permitted limits.
To stay within noise regulations:
- Position the unit away from bedroom windows and neighbouring properties where possible.
- Ensure the unit is mounted on anti-vibration feet or a concrete pad.
- Avoid enclosing the unit in a way that restricts airflow, which can actually increase noise.
Your MCS-certified installer will carry out a noise assessment as part of the design process.
Running Costs
Running costs depend on your home's heat demand, the heat pump's efficiency, and the electricity tariff you are on. Below are illustrative annual figures for a typical three-bedroom semi-detached house.
| Heating system | Annual fuel cost (approx.) |
|---|---|
| Gas boiler (90% efficiency) | £650 – £900 |
| Air source heat pump (SCOP 3.0) | £450 – £650 |
| Ground source heat pump (SCOP 3.5) | £380 – £550 |
| Oil boiler (85% efficiency) | £900 – £1,400 |
| Direct electric heating | £1,500 – £2,200 |
How to Reduce Running Costs Further
- Use a time-of-use tariff — tariffs such as Octopus Go or Economy 7 offer cheaper overnight electricity, and heat pumps can be set to pre-heat the home during off-peak hours.
- Maximise insulation — better insulation means a lower heat demand, which directly reduces running costs. Start with loft insulation if you have not already.
- Set flow temperatures correctly — running the heat pump at a lower flow temperature (35 to 40 degrees Celsius) improves efficiency significantly.
- Use weather compensation — most modern heat pumps have a weather compensation feature that adjusts output based on outside temperature, avoiding unnecessary energy use.
- Add a smart thermostat — smart controls can learn your schedule and optimise heating patterns, saving an additional 10 to 15 percent.
Frequently Asked Questions
How long does a heat pump installation take?
An air source heat pump typically takes two to three days to install. A ground source system can take one to two weeks, depending on whether trenches or boreholes are used.
Will a heat pump work in an older home?
Yes, but you may need to improve insulation and upgrade some radiators first. A thorough home survey will identify what changes are needed. Many Victorian and Edwardian homes are now running heat pumps successfully after insulation improvements.
Do heat pumps work in cold weather?
Modern ASHPs are rated to operate at temperatures as low as minus 15 to minus 25 degrees Celsius. The UK rarely experiences sustained temperatures below minus 5, so performance is reliable throughout winter.
Can I keep my existing radiators?
In many cases, yes. Your installer will calculate the heat output needed for each room. If some radiators are undersized for the lower flow temperatures a heat pump uses, only those specific radiators will need to be upgraded.
What maintenance does a heat pump need?
Heat pumps require minimal maintenance. An annual service check by a qualified engineer — similar to a boiler service — is recommended. This typically costs £100 to £200. Keeping the area around the outdoor unit clear of leaves and debris is the main thing you can do yourself.
Check Your Eligibility for a Grant
The Boiler Upgrade Scheme could cover a significant proportion of your heat pump installation cost. Use our free checker to see what funding you may qualify for.
Check your grant eligibility
Use our free tool to find out if you qualify for UK energy efficiency grants including the Boiler Upgrade Scheme, ECO4, and the Great British Insulation Scheme.
Check your eligibilityPractical Next Steps
- Check your EPC — if your home is rated E or below, consider insulation improvements first.
- Get three quotes — always use MCS-certified installers, as this is required for the BUS grant.
- Ask about SCOP — request predicted seasonal efficiency figures, not just peak COP.
- Explore financing — some installers offer interest-free finance, and the BUS grant reduces the upfront cost substantially.
- Read our related guides — dive into specific topics with our articles on installation costs, heat pump vs gas boiler costs, pros and cons, and available grants.
