Hemp is turning a new leaf. The plant fiber, used to make the sails that took Christopher Columbus' ships to the New World, is now a building material.
In Asheville, N.C., a home built with thick hemp walls was completed this summer and two more are in the works.
The hemp home was built for $133 per square foot, not including land and excavation costs, at the top of a mountain.
Dozens of hemp homes have been built in Europe in the past two decades, but they're new to the United States, says David Madera, co-founder of Hemp Technologies, a company that supplied the mixture of ground-up hemp stalks, lime and water.
The industrial hemp is imported because it cannot be grown legally in this country — it comes from the same plant as marijuana.
Its new use reflects an increasing effort to make U.S. homes not only energy-efficient but also healthier. Madera and other proponents say hemp-filled walls are non-toxic, mildew-resistant, pest-free and flame-resistant.
"There is a growing interest in less toxic building materials, says Peter Ashley, director of the U.S. Department of Housing and Urban Development's Office of Healthy Homes and Lead Hazard Control.
"The potential health benefits are significant," he says, citing a recent study of a Seattle public housing complex that saw residents' health improve after their homes got a green makeover.
The U.S. government has not taken a "systemic approach" to studying chemicals in homes and instead addresses problems such as asbestos, lead, arsenic and formaldehyde only after people get sick, says Rebecca Morley, executive director of the National Center for Healthy Housing, a private research group.
She says green building so far has focused mostly on the environment, not the health of the people inside.
Ashley agrees that federal attention has been "sporadic", but says an interagency group began meeting last year to tackle the issue more broadly. He says HUD is funding more research on the health and environmental benefits of eco-friendly homes.
Some green-rating programs, such as the one run by the private U.S. Green Building Council, give points for indoor air quality.
"We are taking the next step in green-building, " says Anthony Brenner, a home designer with PUSH design, who created Asheville's first hemp home. "We're trying to develop a system that's more health based."
Brenner says he's been searching for non-toxic materials because he wants to build a home for his 9-year-old daughter, Bailey, who has a rare genetic disorder that makes her extremely sensitive to chemicals. "We have to keep her away from anything synthetic," he says, or she'll have seizures...
Continue reading
A waterhole contaminated with heavy oil slick - allegedly from coal seam gas exploration on the Western Downs between Tara and Chinchilla. 
