From Concrete to Hempcrete
Flavell and David Madera, his partner at HT, which is based in Asheville, North Carolina, see hemp as the way of the future. "It is by far the greenest building material on the market right now," says Flavell. Not convinced? Hempcrete, which consists of hemp, lime, and water, is carbon-negative (the mixture requires carbon from the air to dry and seal it), chemical-free, completely biodegradable, fire- and pest-resistant, and vapor-permeable. Another key benefit is hemp's insulation value, which is greater than virtually any other cellulose plant used in construction.
The drawback? Only 16 states allow the production of industrial hemp. Of those, only Maine and Oregon do not require farmers to obtain permission from the federal government to grow the crop. Permission would do little good anyhow, as the FDA sterilizes all hemp seeds before they're imported, creating a catch-22 for would-be hemp farmers. Thus, constructing with hemp is 10 to 20% more expensive than using other building materials.
But if hemp is so sustainable, so cost-effective, and so natural, why is it illegal? Because the federal government still doesn't recognize a difference between hemp and its black-sheep cousin, marijuana. And there is a difference: Hemp contains only negligible amounts of THC, which gives smokers their high, yet is much higher in fiber than marijuana.
Currently, HT imports its hemp from Europe at about 17 cents a pound. The company is scheduled to complete four home using Tradical Hempcrete by the end of the year. HT also plans to open an office in California by next year, where, hemp could be the perfect material to protect from the state's earthquakes. Why? The seismic resistance of Tradical Hempcrete is stronger than most other building materials.