Ground-source heat pump for a barn
Build-cost bands are the site's own indicative model, inflated to a Q2 2026 footing via the ONS Construction Output Price Index (April 2026). Class Q rules current to the 21 May 2024 GPDO amendment.
GSHP installed cost for a 200 m² barn lands at £22,000 to £35,000 after the £7,500 BUS grant. A horizontal slinky array needs ~250-400 m² of ground; vertical boreholes need 2-3 holes at 80-120 m depth.
Slinky vs borehole
- Horizontal slinky: trench-laid loops at 1.2-1.8 m depth. £4,000-£8,000 in ground works. Needs significant garden / paddock area.
- Vertical borehole: 2-3 boreholes drilled to 80-120 m. £8,000-£16,000 in ground works. Best where land is scarce or wet.
Why GSHP is more expensive
The ground array is the cost differential. The heat pump itself is similar to an ASHP. The pay-off is a higher seasonal coefficient of performance (typically 4.0-4.5 vs 3.0-3.5 for ASHP) and quieter operation.
BUS grant
The Boiler Upgrade Scheme grant for ground or water-source heat pumps is £7,500, identical to ASHP. Installer must be MCS-certified.
Sources cited on this page