Hemp fibers were used to build part of the 2022 Olympic facilities. Here’s how.
Some of the venues for this year’s winter games will be hemp-infused, according to the Journal of Commerce by ConstructConnect.
China reportedly ordered large amounts of NForce-Fiber, a concrete reinforcement made with hemp fibers, from Canadian manufacturer Greenfield Technologies last year, to be used in the construction of the bobsledding and luge tracks. The product, launched by Greenfield in 2015, is meant to strengthen concrete and reduce cracks.
Greenfield Technologies’ Vice President Stephen Christenen told the Journal of Commerce the decision to use hemp fibers for these tracks came down to what would create the smoothest, most affordable track in the least amount of time.
While steel, another material used as a concrete additive, is expensive and plastic protrudes from the concrete, making it difficult to finish, NForce-Fiber is relatively affordable, bonds strongly with concrete, and breaks before protruding, making for a smooth surface.
Now, you may be thinking, “Wait, since when was hemp being used in construction?” Here’s your answer:
Industrial hemp products are pervasive across the world, and have been for hundreds of years. Some research even indicates that the Greeks and Romans used hemp for many everyday items. This is because hemp is one of the most durable plants in the world. In fact, the scientific name for hemp, Cannabis Sativa means “useful hemp.”
Hemp has more uses than almost any plant. And, it grows more ubiquitously than most plants as well.
Palm trees, for example, are a very useful and sustainable plant with many uses. But, they can only grow in specific areas and climates. By comparison, hemp grows almost anywhere. It is hardy and resilient, requiring very little care or maintenance.
In a world grasping for more sustainable products, is industrial hemp a solution?
Turns out, some people are already thinking this way.
The same hemp fibers that are being used in the construction of the Olympic bobsledding track this year have been used in numerous structures throughout British Columbia since their release, and hempcrete—a mix of hemp hurds (the core of the plant’s stalk), lime, and sand (or pozzolans) which acts as a construction and insulation material like concrete—is being used in Europe, Canada and, to a lesser degree, in the US to create more sustainable housing.
Hempcrete is different than hemp fiber. While hemp fibers are being used to reinforce concrete, hempcrete is an entirely new type of building material that acts as a replacement for concrete.
But using hempcrete does not come without a cost. First of all, it’s much less strong than concrete, so it shouldn’t be used for the foundation of a structure. On top of that, hempcrete is extremely expensive because of the scarcity of its key ingredient.
Because of the many restrictions of hemp farming in the U.S., industrial hemp is generally imported from Europe and other parts of the world, making it far more expensive than other options. One report says that, in general, the American consumer pays at least $60 more per square foot of hempcrete than they would for concrete.
Overall, there’s no doubt that industrial hemp is growing in popularity. It provides a possible pathway to move away from non-renewable sources to sustainable resources in construction, not to mention the fact that it makes a great luge track. But, with the strict regulations on hemp farming in the U.S. and the restricted uses of hemp-based building materials today, it’s unclear whether it will ever become mainstream.