- Area
- Greater London
- Postcode district
- DA5
- Nation
- England
- Guide price
- From £10,650 inc VAT
- Survey
- Free for installation enquiries
Gas boiler to heat pump in Bexley: what to expect
Every property in Bexley 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.
Installers in Bexley take out the old boiler and flue and seal the wall opening as part of the job. Many gas-heated homes in Bexley have a combi boiler in the kitchen, so the survey starts by finding the right place for a 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
- Combi owners who can find space for a hot water cylinder
- Households ready to give up gas entirely and drop the standing charge
What's included
- Heat pump cylinder, outdoor unit and weather compensation controls
- Free survey with heat loss calculation and cylinder siting
- Removal of the gas boiler, flue and any loft tanks
- Capping of the gas pipe at the boiler position where you are giving up gas
- System flush and radiator upgrades where the design calls for them
Semi-detached and terraced houses in Bexley often have an airing cupboard that can be reused for a heat pump cylinder.
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 Bexley 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.
What to budget for replacing a gas boiler with a heat pump in Bexley
These are guide prices for Greater London, installed and including VAT. Your final price is fixed in a written quote after the survey and depends on the heat loss of the house, the radiators that need changing and where the unit goes.
| 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 Bexley's winters
On the shortest day Bexley 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 Bexley
- Send your postcode and a few details, or use the guide price tool.
- A surveyor visits your Bexley 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 Bexley: questions
Do I need new radiators for a heat pump in Bexley?
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 Bexley home gives a room-by-room list.
Do you cover Bexleyheath as well as Bexley?
Yes. We arrange surveys and installation in Bexleyheath, which is about a mile north of Bexley, and across Greater London.
Where would the outdoor unit go on a Bexley 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 Bexley home.
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.
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.