using Industrial hemp byproducts in construction
The fiber from hemp stalks and the hurds from the stalk’s inner lining continue to show promise in the residential and commercial construction industries. Industrial hemp byproducts can be used in blocks / insulation / landscaping mulch / deck staining oil, often in a more environmentally friendly way than current product offerings.
Industrial hemp is not a load-bearing material, so it is used in conjunction with many products already used in modern construction like lumber. Hemp byproducts also function as concrete reinforcement and thermal and sound insulation.
“Hempcrete” is a bio-composite material combined with a bonding agent, often lime. Other possible bonding agents include gypsum and cement.
The hemp plant is very strong, so it’s fibers are suited for a variety of purposes. Hemp also is acknowledged to sequester carbon dioxide, which is appealing from an environmental perspective. It is also said to be lighter, potentially more resistant to fire, mold, and moisture than regular concrete.
The Ellora Caves in India have been preserved more than 1,500 years thanks to the use of hemp in the building process, a testament to hemp’s longevity.
In 2021, a Sports Center built with hemp byproducts opened in Paris, France.
France has a special place in the modern use of industrial hemp, dating to the 1980’s. While in the process of renovating important buildings that were hundreds of years old, it was discovered that using Portland cement caused moisture to get trapped in the timber frames, rotting and ruining the old buildings.
A study by the French government discovered that a combination of hemp (high silica content) and lime allowed moisture to pass through the building without being trapped, preserving the valuable timber of the historic French buildings.
In addition to European construction, modern hemp homes have been built in places like India and the United States.
The world of architecture has been paying attention.
It is estimated that for a 3,500 square foot home, approximately 2.5 acres of hemp is needed.
While optimism rightfully abounds, there are hurdles for the plant to contend with before it is accepted self-evidently as a construction byproduct. As mentioned above, the product cannot bear the load of a ceiling, so it must be used in concert with other materials.
Hempcrete usually takes about 6-8 weeks to dry completely, so that needs to be taken into consideration for construction projects.
And of course, there is the matter of profitability. The agriculture sector in the United States has spent billions of dollars for developing the optimal growing conditions for corn, soybeans, wheat, cotton, and other products. Adding hemp into the product rotation will be a gradual process.
Despite challenges, investment in industrial hemp as a building material continues.
The largest independent hemp grower in Europe, a Netherlands company called Hemp Flax, has purchased a German natural fiber insulation producer.
In Canada, the Global Hemp Group bought 800 acres of land in Hayden, Colorado, for its HAIZ project to build affordable hemp homes.
