- Area
- Hertfordshire
- Postcode district
- WD7
- Nation
- England
- Guide price
- From £10,000 inc VAT
- Survey
- Free for installation enquiries
Gas boiler to heat pump in Radlett: what to expect
Homes around Radlett range from older terraces to newer estates, and each needs a different design. That is why we survey before we quote.
Installers in Radlett take out the old boiler and flue and seal the wall opening as part of the job. Households across Hertfordshire moving off gas can have a survey in Radlett that compares running costs on realistic assumptions.
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.
- Combi owners who can find space for a hot water cylinder
- Homes in England and Wales eligible for the Boiler Upgrade Scheme
- System or regular boiler homes with an existing airing cupboard
What's included
- Heat pump cylinder, outdoor unit and weather compensation controls
- 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
- System flush and radiator upgrades where the design calls for them
- Commissioning, MCS certificate and grant application in England and Wales where eligible
If your Radlett home still cooks on gas, we talk through whether to keep the supply or switch to an induction hob.
Grants and rules for heat pumps in England
Homes in Radlett 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.
What to budget for replacing a gas boiler with a heat pump in Radlett
The ranges below are typical installed prices for homes in Hertfordshire, including VAT. A survey sets the exact figure, because two similar-looking houses in Radlett 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 | £10,000–£13,150 | £2,500–£5,650 |
| 2–3 bedroom terrace or semi | 5–7 kW | £11,050–£14,200 | £3,550–£6,700 |
| 3 bedroom semi or small detached | 6–9 kW | £12,600–£16,300 | £5,100–£8,800 |
| 4 bedroom detached | 8–12 kW | £14,700–£18,900 | £7,200–£11,400 |
| 5+ bedroom or larger older house | 11–16 kW | £17,350–£23,650 | £9,850–£16,150 |
Installed, inc VAT: unit, cylinder, controls, minor pipework and commissioning.
Short winter days in Radlett and what they mean
On the shortest day Radlett gets about 7 hours 48 minutes of daylight, with the noon sun around 15° up. The heating season runs from autumn into spring, so a heat pump that is sized correctly and set up with weather compensation does most of its work in steady, cool conditions.
What happens after you enquire in Radlett?
- Tell us about your home: postcode, property type and current heating.
- We book a survey in Radlett; the surveyor measures rooms, windows and radiators and looks at cylinder space.
- The design and quote arrive in writing, including radiator changes and the outdoor unit position.
- On installation days the old system is removed and the new one fitted and filled.
- We commission the heat pump, show you the controls and register the installation.
Replacing a gas boiler with a heat pump in Radlett: questions
How soon can you survey a home in Radlett?
Survey dates depend on how busy installers are in Hertfordshire. We offer the next available dates when you enquire and confirm them in writing.
Where would the outdoor unit go on a Radlett 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 Radlett home.
Do I need new radiators for a heat pump in Radlett?
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 Radlett home gives a room-by-room list.
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.
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.

