This is how hemp is being used to build green buildings

When the Pierre Chevet public sports arena opened last year in Croissy-Beaubourg, a small municipality on the outskirts of Paris, it was the first commercial project in France built almost exclusively from hemp blocks.

Many hemp enthusiasts predict that this is just the beginning. Sonia Sifflet, the lead architect on the project for Lemoal Lemoal, a luxury architectural firm in Paris, said she expects to see many more hemp-block projects in France.

“In five years, it will be normal to use hemp blocks,” he said.

Interest in hemp as a viable construction material substitute is growing as developers look for greener options. Hemp can be used in block form, or cast as concrete using “hempcrete,” a combination of lime, hemp fibers, and a chemical binder.

However, building with hemp is hampered by high costs and a supply chain that is not fully formed. And its advocates must overcome resistance to a product that is often mistakenly associated with recreational drug use.

They also claim that hemp offers many environmental benefits that developers and policy makers seek when creating a carbon neutral product that is resistant to fire, mold and weather.

Sifflet added that the hemp blocks do not require special skills to assemble, reducing the number of workers needed on site.

“They come together like Legos,” he said.

Simplicity gives rise to speed: A building made of ready-to-use hemp blocks can reduce the typical production schedule by 20 to 30 percent.

Sifflet said that using hemp blocks raised material costs 30 to 40 percent above that of cement blocks, but the faster production schedule allowed the firm to finish in less time than normal, and the environmental benefits are worth it. some of the higher costs of materials.

In Cape Town, South Africa, the first hemp skyscraper, called 84 Harrington, is built and, at 12 stories, it will be the tallest structure in the world that incorporates mostly hemp construction.

Duncan Parker, co-founder and CEO of Hemporium, a hemp farm in Cape Town, and the owner of the building, noted that the cost of building 84 Harrington was higher because hemp had to be imported from England.

Don Redden is the CEO of Ulmus Development, which is building a mini-warehouse site made of hemp blocks in Kelowna, a city of 130,000 in British Columbia, Canada.

Redden said the building’s carbon equation is tilted to the negative because it will, in fact, draw carbon from the environment. He noted that each block of hemp would isolate about 6 kilos of carbon, more than is emitted in the production and shipping of the blocks.

Rachel Berry, the founder of the Illinois Hemp Growers Association, stated that the first step to increasing hemp construction in the US is to spark the interest of farmers, but the connection of cannabis with hemp may make them reluctant.

By: KEVIN WILLIAMS