Air Source Heat Pump Installation

For grant bands, costs by property size and the county coverage map, see heat pumps Cornwall. A typical air source heat pump installation costs between £8,000 and £14,000 before the grant, depending on system size and property requirements. Indicative Cornwall pricing by property: a 1–2 bed flat or small terrace needs roughly a 5kW unit at £8,000–£9,500 before grant (£500–£2,000 after the £7,500 BUS), with annual running cost around £450–£650; a 3-bed semi typically needs an 8kW unit at £10,000–£12,000 before grant (£2,500–£4,500 after BUS), running around £650–£950 a year; a 4-bed detached usually needs 11–14kW at £12,000–£16,000 before grant (£4,500–£8,500 after BUS), running around £900–£1,300 a year. The average homeowner pays around £5,000 after the grant (government statistics, July 2025). Prices include the heat pump unit, hot water cylinder, any necessary radiator upgrades, controls, and full MCS certification. The up-to-£9,000 Boiler Upgrade Scheme grant applies to BOTH air-source and ground-source heat pumps; to qualify you need a valid EPC (no minimum rating), must own the property, and must be replacing a fossil-fuel heating system. We check your eligibility during the free home survey; the MCS-certified installer applies for the grant and it comes off your invoice. Domestic heat-pump installations also benefit from 0% VAT until March 2027.