Air-source heat pump for a barn conversion
ASHP installed cost for a 200 m² barn lands at £11,000 to £18,000 after the £7,500 Boiler Upgrade Scheme grant. High-volume vaulted barns push capacity into 12-16 kW territory.
Sizing for a barn
A typical 200 m² well-insulated barn loses around 5-8 kW at design conditions; a poorly-insulated vaulted barn can hit 12-14 kW. ASHP capacity is matched to the heat-loss calculation produced by an MCS-certified installer; under-sizing leads to electric immersion top-up; over-sizing cycles the unit and shortens life.
BUS grant
The Boiler Upgrade Scheme pays £7,500 toward an air-source heat pump for English and Welsh properties. The dwelling must be your private property at the date of completion; the installer applies for the grant on your behalf. Barn conversions qualify once they have a postcode and EPC at completion.
An enhanced £9,000 grant runs from 21 July 2026 to 31 March 2027, but only where an off-gas-grid property is replacing an existing oil or LPG heating system. A newly converted barn has no system to replace, so the standard £7,500 applies; do not budget the higher figure.