THESE CANNABIS CONSTRUCTIONS ARE GUARANTEED NOT TO GO UP IN SMOKE
Entrepreneurs are turning to hemp as an alternative material for building homes
It started with Hurricane Katrina: the flooded houses in New Orleans festering with mould, many uninhabitable to this day. Then came the earthquake in Haiti: thousands dead, crushed by homes that should have been their sanctuaries. James Savage, then a Wall Street analyst living on Central Park West, grew disturbed about the conditions he saw on television and in the newspapers.
“There has to be something better we can do than this,” he recalled thinking as he sat at the kitchen table inside his new home on a cliff overlooking the Hudson River in Stuyvesant, about 200km north of New York City.
The solution he has come up with is not some space-age polymer or recycled composite but a material that has been in use for millennia, though it is more often demonised than venerated in the US.
“Who knew hemp would be the answer to what we were looking for?” said Mr Savage, who started a company to create building materials derived from cannabis.
Now that the forbidden plant is enjoying mainstream acceptance, Mr Savage is hoping to put hemp to use not in joints but between joists. His first project has been his own 1850s farmhouse, though he says he believes hemp-based building materials could transform both agriculture and construction throughout New York.
While cannabis has had a long history as a fibre used in ropes, sails and paper products — presidents George Washington and Thomas Jefferson both grew it — Mr Savage is among a small number of entrepreneurs who have instead turned to a novel application known as hempcrete.
Hempcrete is made using the woody, balsa-like interior of the Cannabis sativa plant (the fibre for textiles comes from the outer portion of the stalk) combined with lime and water. Though it lacks the structural stability its name might suggest, hempcrete does provide natural insulation that is air-tight yet breathable and flexible. It is free from toxins, impervious to mould and pests and virtually fireproof.
“I know, I know, everyone talks about our buildings going up in smoke, but the joke is on them,” Mr Savage said. In England, some insurers actually provide a discount for hempcrete because of its durability.
And because the material is grown rather than mined, like traditional cement, or manufactured, like fibreglass, it gives new meaning to green building. Mr Savage envisions a “hemp basket” stretching across New York’s rugged farmlands supplying locally sourced insulation throughout the northeast.
What hemp is not, as advocates constantly remind people, is a drug.
“You could smoke a telephone pole’s worth of our stuff and still not get high,” said Ken Anderson, whose company, Original Green Distribution, based in Minneapolis, makes a hempcrete marketed as Hempstone.
The strain of plant grown for hempcrete contains no more than 0.3% of THC, the active ingredient in marijuana. That is compared with 5-10% found in the hallucinogenic and medicinal varieties.
“It’s like the difference between a wolf and a poodle,” Mr Savage said. “Same species, totally different animal.” Even so, both were outlawed starting in the 1930s.
Though the illicit aspects of hemp may have held it back in the US, marijuana’s growing popularity could finally be helping hemp’s spread. “Some people thought hemp might help get marijuana accepted, but it’s going the other way around,” said Eric Steenstra, executive director of the Hemp Industries Association. “I don’t think you’d see quite the same excitement if we were building with flax or jute.”
Yet federal regulators remain dubious, with virtually no domestic hemp production. It is legal to use it, but generally not to grow it. The farm bill passed last year began to allow for hemp-farming pilot projects, and while New York and Connecticut have both begun programmes, no crops have been planted. At the moment, all raw material must be imported, and last year, Canada alone shipped $600 million of hemp to US businesses.
A bigger hurdle may be getting hemp-lined homes past building inspectors.
“If you show them two-by-fours filled with fibreglass, they know what they’re dealing with, but you mention hemp, and they scratch their heads,” said Tim Callahan, an architect in Asheville, North Carolina. He has worked on about a dozen hempcrete structures, including what is thought to be the first home in this country to use hempcrete, built in 2010.
Yet hempcrete presents its own issues, particularly the need for thicker insulation than traditional materials.
Even in Brooklyn, where it would seem a natural fit, hempcrete has been a tough sell for Gennaro Brooks-Church, a contractor who specialises in green building. “When a client is spending $2 million [68 million baht] on a brownstone and sinking in another $1.5 million on renovations, you’ll be hard pressed to get them to sacrifice even an inch of space,” he said.
For his part, Mr Savage was never able to bring his product to Haiti — he blames Haitian fears of US law enforcement — and an effort in Mali failed because of a 2012 coup. Around that time, the first marijuana decriminalisation laws began to pass in the United States, so he turned his focus closer to home.
To foster wider acceptability, Mr Savage and his three-year-old business, Green Built, which he runs out of his hemp-lined home office, is working toward developing a panelised system. Akin to drywall, it would be easier to market and install than poured hempcrete, he says. And, combining housing trends, he is developing a 37-square-metre “tiny house” made up of two or three circular, shippable hempcrete modules.
His only project so far has been turning his red brick farmhouse into a hempcrete laboratory, where many of the walls have been insulated with it, eliminating his need for air conditioning.
Mr Savage said his hemp rooms even smell different, though not the way most people might expect. “It has a freshness to it,” he said.