How Deep Is the Borehole for a Ground Source Heat Pump?

Typical Borehole Depths Explained

Vertical borehole systems are the most space-efficient option for ground source heat pumps. The depth required depends on your heating needs and local geology.

Factors Affecting Borehole Depth

• Heat demand: Larger or less efficient homes need more heat extraction capacity
• Ground geology: Rock conducts heat better than clay, affecting required depth
• Multiple boreholes: Sometimes 2-3 shallower boreholes are more cost-effective
• Groundwater: The presence of groundwater can improve heat transfer efficiency

Borehole Drilling Process

Professional borehole drilling typically takes 2-3 days per borehole. The process involves:

1. Site survey and geological assessment
2. Drilling rig setup (requires approximately 6m x 4m access)
3. Drilling and casing installation
4. Loop pipe insertion
5. Grouting and sealing
6. Connection to heat pump system