Horizontal Ground Loop

What is a horizontal ground loop?

A horizontal ground loop is a series of plastic underground pipes filled with a heat-transfer fluid and buried at shallow depths over a wide swath of land. 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 horizontal ground loops installed?

Workers use backhoes or chain trenchers to dig trenches and install the ground loops. The piping is sometimes stacked or coiled into a slinky shape to maximize available space. The installation crew then backfills the trenches.

How much space do you need to install a horizontal ground loop?

An ideal property for horizontal ground loops will have at least ¼ to ½ acre of land available. The loop is installed over a wide area of ground and requires enough space to dig trenches several hundred feet long and 5-10 feet deep.

How much does it cost to install a horizontal ground loop?

It costs an installer on average $1,000-$2,000 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 $5,000 to $10,000 to install just the horizontal ground loops.

Installing horizontal ground loops is generally less expensive than installing vertical ground loops because of the necessary equipment. 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 are.

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 suburban and urban 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 manually dig 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 horizontal ground loops, check out these frequently asked questions.