- Area
- Kent
- Postcode district
- TN14
- Nation
- England
- Guide price
- From £9,800 inc VAT
- Survey
- Free for installation enquiries
Gas boiler to heat pump in Westerham: what to expect
The question for a Westerham home is rarely whether a heat pump can work, but what needs to change to make it work well: radiator sizes, pipework, controls and where the unit goes.
Many gas-heated homes in Westerham have a combi boiler in the kitchen, so the survey starts by finding the right place for a cylinder. Rear gardens and side returns in Westerham usually offer a sensible spot for the outdoor unit, checked for airflow and neighbours.
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.
- Households ready to give up gas entirely and drop the standing charge
- System or regular boiler homes with an existing airing cupboard
- 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
- Capping of the gas pipe at the boiler position where you are giving up gas
- Commissioning, MCS certificate and grant application in England and Wales where eligible
- Removal of the gas boiler, flue and any loft tanks
- Free survey with heat loss calculation and cylinder siting
Semi-detached and terraced houses in Westerham often have an airing cupboard that can be reused for a heat pump cylinder.
Grants and rules for heat pumps in England
Homes in Westerham 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.
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 Westerham
The ranges below are typical installed prices for homes in Kent, including VAT. A survey sets the exact figure, because two similar-looking houses in Westerham 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 | £9,800–£12,900 | £2,300–£5,400 |
| 2–3 bedroom terrace or semi | 5–7 kW | £10,800–£13,900 | £3,300–£6,400 |
| 3 bedroom semi or small detached | 6–9 kW | £12,350–£15,950 | £4,850–£8,450 |
| 4 bedroom detached | 8–12 kW | £14,400–£18,550 | £6,900–£11,050 |
| 5+ bedroom or larger older house | 11–16 kW | £17,000–£23,200 | £9,500–£15,700 |
Installed, inc VAT: unit, cylinder, controls, minor pipework and commissioning.
Designing for Westerham's winters
Westerham sees roughly 7 hours 52 minutes of daylight in late December against 16 hours 36 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.
The steps for replacing a gas boiler with a heat pump in Westerham
- Start online with a guide price or call us.
- A home survey in Westerham gives us the room-by-room heat loss.
- Your written quote sets out the design, the price and the grant position where you live.
- Installation is booked for dates that suit you; most homes take 2–4 days on site.
- After commissioning you get a handover of the controls and settings, plus the certificates.
Replacing a gas boiler with a heat pump in Westerham: questions
Do I need new radiators for a heat pump in Westerham?
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 Westerham home gives a room-by-room list.
How long does a heat pump survey take in Westerham?
A home survey in Westerham usually takes one to two hours. The surveyor measures every heated room, checks windows, walls and radiators, and looks at where the outdoor unit and cylinder can go.
Where would the outdoor unit go on a Westerham 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 Westerham home.
Can a heat pump replace a combi boiler?
Yes, but you need room for a hot water cylinder, because heat pumps store hot water rather than heating it on demand. Most homes find a space in a cupboard, utility room, garage or under the stairs, and compact or combined indoor units help where space is tight. The survey measures the options first, so you know where everything will go before you accept the quote.
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.