What is a vertical ground loop?
A vertical ground loop is a series of plastic underground pipes filled with a heat-transfer fluid and installed in one or more boreholes about 200 to 500 feet deep in the ground. The loop connects to an indoor geothermal heat pump and uses the ground as a heat source or heat sink.
It’s also a type of closed-loop geothermal system. That means the heat-transfer fluid continuously circulates: no fluid can escape, and no outside materials can enter.
How are vertical ground loops installed?
A contractor uses well-drilling equipment to bore one or more 6-8 inch diameter vertical holes in the ground 200-500 feet deep. A single pipe loop with a U-bend at the bottom is then inserted in the bore hole. The hole is filled with grout from bottom to top.
If your home needs more than one hole, they’re drilled about 20 feet apart.
How much space do you need to install a vertical ground loop?
Vertical ground loops are ideal for suburban or urban areas where space is limited. Each borehole is small in diameter, so the only potential limiting factor is adequate space for large, heavy drilling equipment.
How much does it cost to install a vertical ground loop?
It costs an installer on average $1,600-$4,250 per heat pump ton to install the ground loop.
If a typical 2,000 sq. foot home requires a 5 ton heat pump, it might cost an installer about $8,000 to $21,250 to install just the vertical ground loops.
Installing vertical ground loops is generally more expensive than installing horizontal ground loops because the necessary equipment for vertical installation is more expensive. Horizontal ground loops are long but shallow, so installers use a backhoe or a chain trencher to dig them. Vertical ground loops require a drill rig to drill one or more holes several hundred feet deep and a grout machine to fill in these holes. Trenchers and backhoes are simply more affordable to acquire and operate than drill rigs.
Which is better: vertical or horizontal ground loops?
The loop type that’s best for your home is the one you have space for! Horizontal loops are a good option for vast, rural properties. For many homeowners, though, vertical ground loops are the best and only option due to space constraints and local geography. For example, it can be challenging to trench through but relatively easy to drill through layers of bedrock.
When properly sized, designed, and installed, vertical and horizontal loops are equally effective at keeping your home comfortable.
To learn more about vertical ground loops, check out these frequently asked questions.