If someone said the word “hemp,” the first thing to spring to mind probably wouldn’t be home construction. But if you’re looking for a strong, green, energy-efficient building material that’s resistant to pretty much everything, hemp might be your best choice.
This is the concept being pitched by Greg Flavall and David Madera, owners of an Asheville-based business called Hemp Technologies. They’re some of the first to build with the material in the United States, where industrial hemp hasn’t seen the rise in popularity it enjoys in other countries, thanks to a federal ban on U.S. production.
Its recognition is slowly ramping up, though, due in part to its benefits over standard concrete. The third house in the country to be built with the technology is going up now, in the mountains above Lake Junaluska.
Roger Teuscher, the homeowner, said he was turned on to the idea by his first architect, who suggested the plant as a cleaner, greener alternative to standard homebuilding supplies. Tuescher, who lives most of the year in Florida, said he was drawn not only to the cost savings gained by increased insulation, but by the product’s recyclability.
“The whole house can be recycled,” said Teuscher. “The house itself you can take down, grind it up and put it back into another house.”
And that’s a far cry from standard concrete homes. But Flavall, whose company is providing the hemp for Teuscher’s home, said that with hemp-built homes, it’s unlikely that he’d ever need to do that. While standard American homes have a shelf life of about 80 years, hemp-made homes will last much longer. The oldest known hemp structure, said Flavall, is a Japanese building that’s been standing for just more than three centuries.
For most customers, though, the real selling points are the product’s environmental friendliness and energy efficiency.
Because the hemp is mixed with lime to create the hempcrete that makes up walls, floors and ceilings, it is actually carbon negative – meaning it takes carbon from the air and locks it up into the fabric of the building. In the simplest terms, lime needs carbon to continue existing and hemp is a breathable substance, so hemp buildings will suck significant amounts of carbon from the air during the building process and will continue to breathe for the life of the structure.
Flavall said that this, combined with high levels of resistance to things like fire, mold, termites and other insects and the plant’s extreme capacity for insulation, make it the ideal building material.
Flavall, a Canadian-educated New Zealand native, said he and partner Maderan stumbled across the glories of industrial hemp four years ago, while on a quest for sustainable materials. Now, he’s practically an evangelist for the plant and its benefits.
“It’s a miracle plant,” said Flavall. “In Canada they grow it as a break crop [to relieve the soil between crops] and they are getting a 27 percent increased yield after the hemp crop, because industrial hemp puts nitrogen back into the soil.”
And it’s true that industrial hemp has a variety of uses, both in and out of the ground for things beyond just building.
But industrial hemp in the U.S. isn’t all sweetness and light. It is around 10 to 15 percent more expensive to build a house out of hemp than via traditional methods. The price hike is thanks to all that pesky importing; although 16 states have granted permission for the growth of industrial hemp, the federal government still has a ban on bringing in the seeds to get the crop going.
For the sake of clarity, it begs explaining that industrial hemp isn’t the same as that other, more mind-bending variety of hemp that has garnered a bad reputation and a Schedule I Controlled Substance label from the Drug Enforcement Agency. It’s a biological cousin of that plant, but is missing the key ingredient — THC — which is the chemical that causes a high.
Flavall said that it was really lobbying in the early 20th century that kept industrial hemp out of American farms, and he is now doing his own lobbying to get those federal laws changed. He sees hemp as a potential boon to the nation’s economy, especially in areas such as Western North Carolina, where the money once raked in by tobacco has long since begun to dry up.
“It’s easier to get a license to grow medical marijuana than it is to grow industrial hemp,” said Flavall. “But there’s enough pressure now with thousands of people around the nation advocating for famers to be able to grow. America imported $350 million of industrial hemp product (last year).”
Another downside to the product is time; the process is more time-consuming, takes longer to mix and longer to apply, said Vinny Cioffi, the Waynesville contractor in charge of building Teuscher’s new home.
“It was a little more labor intensive and it’s a little more expensive,” said Cioffi. “But I hope it catches on because it’s more energy efficient and because of all the other benefits of it.”
And Flavall thinks it’s really only a matter of time before that happens. The technology has been widely used across Asia and Europe for several decades to fairly wide approval, thanks to the cost-savings it’s introduced. In the United Kingdom, the Adnams Brewery was able to build a large distribution center without an air conditioning system because the hempcrete was insulation enough to cool the stored beer, and it saved the company £400,000, just more than $640,000.
Meanwhile, Flavall and his company will stick to importing, trusting that the benefits to the environment and the wallet will continue to bring them clients eager to claim those benefits for themselves.