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High-Density Polyethylene (HDPE)

What is HDPE?

High-density polyethylene is a versatile plastic valued for being both lightweight, strong, inexpensive, and easy to recycle. Today, it’s the world’s most widely used type of plastic.

Why is HDPE so popular?

HDPE has a few properties that make it so popular:

  1. It’s malleable – it can be easily molded into any shape or form.
  2. It’s strong – it’s hard to tear, hard to burst, and hard to damage.
  3. It’s long-lasting – it resists mold, mildew, rotting, strong acids, and most chemicals found in even harsh cleaners and detergents.

What things are made with HDPE?

So many! Some examples include milk jugs, cutting boards, toys, soda bottles, traffic cones, and cereal box liners. Our personal favorite is, of course, geothermal ground loops.

Why are geothermal ground loops made with HDPE?

HDPE ground loops are extremely robust against corrosion and chemical damage, which means the normal (or abnormal) movement of water and fluids underground will virtually never harm them. High-density polyethylene (HDPE) and crosslinked polyethylene (PEXa) are the only materials formally approved for closed-loop geothermal systems by the International Ground Source Heat Pump Association (IGSHPA).

Geothermal ground loops made from HDPE last 50+ years — even up to 100 years! Once installed, the buried ground loop will be a permanent fixture on the property for as long as there is a building to heat and cool.