- Area
- Hertfordshire
- Postcode district
- AL8
- Nation
- England
- Guide price
- From £10,000 inc VAT
- Survey
- Free for installation enquiries
Before you book: air source heat pump installation in Welwyn Garden City
In Welwyn Garden City, as anywhere in the UK, the heat pumps that perform well are the ones designed around low flow temperatures and sized from a proper heat loss calculation.
Terraced streets in Welwyn Garden City often mean a compact unit position at the rear, so siting and sound levels are checked carefully. Many homes in Welwyn Garden City have a side passage or rear garden with room for an outdoor unit, and the survey checks airflow and distance from neighbouring windows.
We survey your home, design a heat pump system around its real heat loss, and manage the installation from the first visit to the MCS certificate.
- Houses with reasonable insulation, or a plan to improve it
- Homes replacing a gas, oil, LPG or electric heating system
- Households with room for a hot water cylinder
What's included
- Commissioning, handover and a walk-through of the controls
- Outdoor unit, hot water cylinder and weather compensation controls
- System design, unit sizing and a written quote
- Boiler Upgrade Scheme application in England and Wales where eligible
- Free home survey and room-by-room heat loss calculation
Homeowners across Hertfordshire can arrange a survey in Welwyn Garden City for a room-by-room design and a written quote before committing to anything.
Grants and rules for heat pumps in England
Homes in Welwyn Garden City 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 air source heat pump installation in Welwyn Garden City
These are guide prices for Hertfordshire, 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 | £10,000–£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.
Designing for Welwyn Garden City's winters
On the shortest day Welwyn Garden City gets about 7 hours 46 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.
How installation works in Welwyn Garden City
- Send your postcode and a few details, or use the guide price tool.
- A surveyor visits your Welwyn Garden City 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.
Air source heat pump installation in Welwyn Garden City: questions
What size heat pump does a Welwyn Garden City 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 Welwyn Garden City home.
How soon can you survey a home in Welwyn Garden City?
Survey dates depend on how busy installers are in Hertfordshire. We offer the next available dates when you enquire and confirm them in writing.
How long does installation take in Welwyn Garden City?
Most installations take 2–4 days on site. Jobs with several radiator changes or new pipework take longer, and your quote for a Welwyn Garden City home states the expected time.
Will an air source heat pump be noisy?
Heat pumps are designed to run quietly, but where the unit sits makes a real difference. The survey looks for a position away from bedroom windows and neighbours, with clear airflow, and the installation must pass the MCS noise assessment. The fan is most noticeable on very cold days when the unit works hardest, and a little vapour during the periodic defrost is normal.
Do I need new radiators for a heat pump?
Not always; many homes keep most of their radiators and change only a few. Because a heat pump runs at a lower water temperature than a boiler, each radiator gives out less heat, so the survey checks every room against its heat loss. Rooms where the existing radiator falls short get a larger one, with a guide price of £250–£450 each, installed and including VAT.

