If the land area available is limited, a vertical loop may be installed for the geothermal piping.
Vertical installations might also be used where the land is too rocky for trenching, for existing buildings, and for large commercial or educational facilities.
To install a vertical loop, a contractor will bore holes into the ground. Long, hairpin-shaped loops of pipe are then inserted. The hole is backfilled, plugged or grouted, and the pipes are connected to headers in a trench leading back to the building.
The drilling depth is determined by the lowest total cost based on the conditions at the job site. A typical borehole depth is 150 to 250 feet.
The objective of a vertical borehole is to install a specific amount of pipe, not to reach a certain depth. If 600 feet of pipe are required, three 200-foot boreholes are acceptable and may be more cost-effective.
Drilling boreholes for geothermal loops is much simpler than drilling to find well water. The borehole is generally smaller, which reduces drilling time, and no casing is required because the hairpin-shaped loop is the casing.
Learn more about: Designing a Vertical Loop System