CNN report on eco friendly sustainable hemp house built in Asheville, NC. Benefits include carbon negative construction, breathability, and reduced cost of heating and cooling. Imagine you had a building material that was energy-efficient, non-toxic and resistant to mold, insects and fire. The material may even have a higher R-value, or thermal resistance, than concrete, a claim that is still being investigated.The only problem? The base of the Hempcrete creation is hemp, which comes from the cannabis sativa plant -- the same one that produces marijuana, which is a federally banned substance. Because of this, industrial hemp production is illegal in the United States.Still, the Hempcrete mixture of hemp, lime and water is being used to some extent for construction jobs across America. One of the companies working with Hempcrete is Hemp Technologies, a construction company based in North Carolina that is adamant about the advantages of building using Hempcrete. They’ve built homes out of hemp in Hawaii, Texas, Idaho and North Carolina, where they are currently working on a project known as “NauHaus.”Throughout Europe, the use of hemp for construction purposes has spread across many countries. "We got started about three years ago and I was looking for sustainable building products, Hemp Technologies co-founder David Madera told GOOD Design. [Co-founder Greg Flavall] was in Europe, found Hempcrete and we basically did a tour of Europe and looked at everything that they had done in the U.K., France, Belgium, and Switzerland. We did our first seminar in 2009, and it was the most important thing that helped promote it.”Seeing Hempcrete as a more efficient and sustainable building material has led to some dubbing it as a gateway product. The people behind the U.K.-based Tradical Hemcrete are using their hemp based product to create a carbon negative thermal walling material. Hempcrete can be used for everything from roof installation to flooring to wall construction. The creators of the Carson, California-based HempTraders.com, distributors of “fine hemp products”, sell Hempboard. Hempoboard is a medium density fiberboard made from 100 percent hemp hurds and can be used to make environmental furniture, counter tops, walls and shelving.