- Area
- Greater London
- Postcode district
- SW13
- Nation
- England
- Guide price
- From £10,650 inc VAT
- Survey
- Free for installation enquiries
Gas boiler to heat pump in Barnes: what to expect
Every property in Barnes is different, so the design starts from measurements rather than a rule of thumb. That keeps the system the right size and the running costs predictable.
Rear gardens and side returns in Barnes usually offer a sensible spot for the outdoor unit, checked for airflow and neighbours. Semi-detached and terraced houses in Barnes often have an airing cupboard that can be reused for a heat pump cylinder.
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.
- Boilers that are old, unreliable or due for replacement
- Homes in England and Wales eligible for the Boiler Upgrade Scheme
- Combi owners who can find space for a hot water cylinder
What's included
- Removal of the gas boiler, flue and any loft tanks
- Commissioning, MCS certificate and grant application in England and Wales where eligible
- System flush and radiator upgrades where the design calls for them
- Free survey with heat loss calculation and cylinder siting
- Capping of the gas pipe at the boiler position where you are giving up gas
Households across Greater London moving off gas can have a survey in Barnes that compares running costs on realistic assumptions.
Grants and rules for heat pumps in England
In England the Boiler Upgrade Scheme gives £7,500 towards an air source heat pump (£9,000 if it replaces oil or LPG, from 21 July 2026 to 31 March 2027), and since 28 April 2026 a valid EPC is no longer needed. The grant is applied for by the MCS-certified installer and shown as a deduction on your Barnes quote.
Installing heat pumps is zero-rated for VAT across the UK until 31 March 2027. Since 29 May 2025, permitted development in England allows up to two air source heat pumps on a house, each up to 1.5 m³, with no blanket 1 m boundary rule — the installation must still meet the MCS planning standards, including the noise check. Listed buildings, flats and some conservation-area positions need extra consent, which we check at survey.
Gas boiler to heat pump costs around Barnes
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 Barnes 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.
Designing for Barnes's winters
Barnes sees roughly 7 hours 50 minutes of daylight in late December against 16 hours 38 minutes in June. Milder southern winters suit heat pumps well, though the system is still sized for a cold snap rather than an average day.
How installation works in Barnes
- Send your postcode and a few details, or use the guide price tool.
- A surveyor visits your Barnes 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 Barnes: questions
What size heat pump does a Barnes home need?
It depends on the heat loss, not the postcode. As a rough guide, a 3 bedroom semi often needs 6–9 kW, but the room-by-room survey sets the actual size for your Barnes home.
How soon can you survey a home in Barnes?
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.
Do I need new radiators for a heat pump in Barnes?
Often some, not all. Heat pumps run best at lower water temperatures, so rooms with small radiators may need larger ones. The survey of your Barnes home gives a room-by-room list.
Should I have my gas meter removed?
If gas is used for nothing else, removing the meter ends the gas standing charge, which is about £108 a year at the October to December 2026 price cap. If you still cook on gas or have a gas fire, you will need to keep the supply. Meter removal is arranged through your gas supplier, usually once the heat pump is running; the pipe at the boiler position is capped during the installation.
Is there a grant to replace a gas boiler with a heat pump?
In England and Wales, the Boiler Upgrade Scheme gives £7,500 towards an air-to-water heat pump that replaces a gas boiler, for eligible owners of existing homes. The MCS-certified installer applies to Ofgem and deducts the grant from your quote, and Ofgem contacts you to confirm. Scotland has separate Home Energy Scotland funding, and Northern Ireland has no dedicated homeowner grant at present.

