Design starts with the load: a heat loss calculation for the building, its occupancy and opening hours, how much hot water it uses and whether any spaces need cooling. From that we propose plant sizes and positions, on a roof, in a yard or in a plant enclosure, with the structural, electrical and noise checks each position needs. Larger plant may need a three-phase supply, which the network operator may need to provide or confirm.
Offices and shops in West Sussex with a flat roof or rear yard often have space for outdoor plant, checked for structure and access. Landlords and managing agents in West Sussex can phase the work to keep tenants and staff comfortable during the switchover. Premises in West Sussex close to homes need careful plant siting and, where required, an acoustic assessment.
Who it suits
- Offices, shops and small commercial premises replacing gas or oil boilers
- Buildings with roof or yard space for outdoor plant
- Landlords and managing agents planning low-carbon upgrades
- Blocks of flats and houses in multiple occupation needing shared or per-flat systems
Grants and rules for heat pumps in England
Homes in West Sussex 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.
Prices
Commercial systems are priced after a site survey and load calculation.
Towns we cover in West Sussex
We cover 14 towns in West Sussex for commercial heat pump installation. Each links to local guide prices and the grant position for England.
| Town | Postcode district | Nearest town | Midwinter daylight |
|---|---|---|---|
| Crawley | RH11 | Horley | 7 h 53 min |
| Worthing | BN11 | Shoreham-by-Sea | 7 h 56 min |
| Bognor Regis | PO21 | Chichester | 7 h 57 min |
| Littlehampton | BN17 | Arundel | 7 h 56 min |
| Horsham | RH12 | Crawley | 7 h 54 min |
| Haywards Heath | RH16 | Burgess Hill | 7 h 55 min |
| Chichester | PO19 | Bognor Regis | 7 h 56 min |
| Burgess Hill | RH15 | Haywards Heath | 7 h 55 min |
| East Grinstead | RH19 | Crawley | 7 h 53 min |
| Shoreham-by-Sea | BN43 | Worthing | 7 h 56 min |
| Emsworth | PO10 | Havant | 7 h 56 min |
| Arundel | BN18 | Littlehampton | 7 h 56 min |
| Midhurst | GU29 | Petworth | 7 h 55 min |
| Petworth | GU28 | Midhurst | 7 h 55 min |
Commercial heat pump installation questions
How much does a commercial heat pump cost?
Commercial heat pumps are priced after a site survey, because cost depends on the building's heat load, the number and size of units, where the plant goes, access, and any changes to the heating system inside. We then give a written quote setting out the equipment, the programme and what is included. There is no reliable guide price for commercial work without seeing the building.
Can commercial heat pumps provide cooling as well?
Some can. Air-to-water heat pumps are mainly used for heating and hot water, but certain units can also supply chilled water for fan coil units. Air-to-air systems heat and cool directly through indoor units and suit offices and shops where cooling is wanted. The survey identifies which areas need cooling and recommends a system to match.
Can heat pumps go on a flat roof?
Yes, flat roofs are a common position for commercial plant. The roof needs a structural check for the weight of the units and their frames, and the installation usually needs a lifting plan, anti-vibration mounts, drainage for defrost water and safe access for maintenance. Pipe and cable routes from the roof into the building are planned at survey.
Can you install without closing the business?
Usually, yes. Outdoor plant, pipework and controls can often be installed while the existing heating still runs, with the switchover planned for a short window, such as a weekend or a quieter time of year. Work inside occupied areas can be phased. The programme in your quote sets out what happens when, so you can plan staff and customers around it.

