Houses of Hemp

In the U.S. alone, the construction of buildings account for thirty-eight percent of carbon emissions, fueling a demand for carbon neutral and zero footprint alternatives. Now, innovative builders have found a modern solution in an ancient material.

“Since the beginning of time, hemp is the only plant that can feed you, house you, clothe you and heal you,” says Cliff Thomason of Oregon Hemp Company, who grows industrial hemp for thousands of uses.

Once banned with marijuana, hemp contains only trace amounts of THC and is not intoxicating. The plant can be grown and harvested on bad soil over and over again in the same space very quickly, unlike precious trees.
They don’t call it “weed” for nothing.

It is the waste part of the plant that is used in construction, spelledH U R D, “hurd” is the woody core leftover after the fiber’s been extracted. Ten times stronger than concrete and one sixth the weight, “hempcrete” is an all-natural material made of nothing but hemp pulp, a lime binder and water. It doesn’t require power tools and it’s nontoxic, making it easy and safe to work with.

When mixed, hemp hurds produce a fluffy, dry “concrete” with a sawdust consistency that is poured and manually tamped down in place, using boards to mold the walls. Once it’s dried, the boards are pulled away and the thick walls are covered in a lime plaster that will enable them to last hundreds of years.

Hempcrete is mold resistant, rot resistant, pest resistant, and fire-resistant, making it a green-building favorite over cob or adobe.

And amazingly, this ancient, once illegal plant, creates buildings that are not only energy efficient, they actually trap carbon, making our world a cleaner and healthier place for all.