- Area
- Greater London
- Postcode district
- SW4
- Nation
- England
- Guide price
- From £10,650 inc VAT
- Survey
- Free for installation enquiries
Gas boiler to heat pump in Clapham: what to expect
A heat pump suits most Clapham homes, but the details decide how efficiently it runs. Our survey looks at insulation, radiators and hot water use room by room.
Many gas-heated homes in Clapham have a combi boiler in the kitchen, so the survey starts by finding the right place for a cylinder. Installers in Clapham take out the old boiler and flue and seal the wall opening as part of the job.
Moving from mains gas to a heat pump means finding cylinder space, deciding what happens to the gas supply and comparing running costs on realistic assumptions.
- Homes in England and Wales eligible for the Boiler Upgrade Scheme
- Boilers that are old, unreliable or due for replacement
- Combi owners who can find space for a hot water cylinder
What's included
- System flush and radiator upgrades where the design calls for them
- Commissioning, MCS certificate and grant application in England and Wales where eligible
- Capping of the gas pipe at the boiler position where you are giving up gas
- Removal of the gas boiler, flue and any loft tanks
- Free survey with heat loss calculation and cylinder siting
Households across Greater London moving off gas can have a survey in Clapham that compares running costs on realistic assumptions.
Grants and rules for heat pumps in England
Homes in Clapham can use the Boiler Upgrade Scheme, which takes £7,500 off the cost of an air source heat pump when it replaces fossil-fuel or electric heating. Replacing oil or LPG heating qualifies for £9,000 for installations from 21 July 2026 to 31 March 2027, and air-to-air systems for £2,500. The MCS-certified installer named in your quote applies for the grant and deducts it from the price.
There is no VAT on installing a heat pump anywhere in the UK until 31 March 2027. In England most houses can have an air source heat pump under permitted development, provided the unit meets the MCS noise and siting standards; the old 1 m boundary limit was removed on 29 May 2025. We flag listed buildings, flats and sensitive conservation-area positions at survey.
Guide prices for replacing a gas boiler with a heat pump in Clapham
The ranges below are typical installed prices for homes in Greater London, including VAT. A survey sets the exact figure, because two similar-looking houses in Clapham can need quite different radiators and pipework.
| Home | Typical size | Installed guide price | After £7,500 grant |
|---|---|---|---|
| 1–2 bedroom flat or small terrace | 4–5 kW | £10,650–£14,000 | £3,150–£6,500 |
| 2–3 bedroom terrace or semi | 5–7 kW | £11,750–£15,100 | £4,250–£7,600 |
| 3 bedroom semi or small detached | 6–9 kW | £13,450–£17,350 | £5,950–£9,850 |
| 4 bedroom detached | 8–12 kW | £15,700–£20,150 | £8,200–£12,650 |
| 5+ bedroom or larger older house | 11–16 kW | £18,500–£25,200 | £11,000–£17,700 |
Installed, inc VAT: unit, cylinder, controls, minor pipework and commissioning.
Winter daylight and heating in Clapham
On the shortest day Clapham gets about 7 hours 50 minutes of daylight, and the winter sun reaches only around 15° above the horizon at noon. Winters this far south are milder than in most of the UK, which helps a heat pump run at low flow temperatures for much of the season.
The steps for replacing a gas boiler with a heat pump in Clapham
- Send your postcode and a few details, or use the guide price tool.
- A surveyor visits your Clapham home, measures every room and checks where the outdoor unit can go.
- You receive a heat loss design and a fixed written quote, with any grant shown where it applies.
- Installers fit the unit, cylinder and any radiator changes, typically over 2–4 days on site.
- The system is commissioned, set up with weather compensation and handed over with the paperwork.
Replacing a gas boiler with a heat pump in Clapham: questions
How soon can you survey a home in Clapham?
Survey dates depend on how busy installers are in Greater London. We offer the next available dates when you enquire and confirm them in writing.
Can you service a heat pump in Clapham that someone else installed?
Yes. We arrange servicing and repairs for most air source heat pumps in Clapham, whoever fitted them. Tell us the make and model when you book.
Where would the outdoor unit go on a Clapham house?
Usually at the side or rear, on a level base with space around it for airflow and servicing, away from bedroom windows where possible. The surveyor checks positions at your Clapham home.
What if my gas boiler is fairly new?
A newer boiler can still be replaced, but the timing is worth weighing. Some owners switch when the boiler needs a major repair; others prefer to plan the change for a convenient time. Across the UK, heat pump installation is zero-rated for VAT until 31 March 2027. A hybrid system, which keeps the boiler alongside a heat pump, is another option, though it is not eligible for the Boiler Upgrade Scheme in England and Wales.
Will my hot water run out with a heat pump?
Not if the cylinder is sized properly for your household. The survey asks how many people live in the home, how many bathrooms you have and whether you prefer baths or showers, then sizes the cylinder to suit. The heat pump reheats the cylinder on a schedule, often overnight and again during the day, and an immersion heater acts as a backup.