This versatile, green building material is banned from commercial production in the U.S.
By Jon Walton, Construction Digital
The farcical war on drugs that has incarcerated millions, cost taxpayers billions, and led to the deaths of untold numbers of domestic and international civilians, is also smothering an industry with the potential to reduce the carbon footprint of the building sector, one of the largest polluters on the planet.
Hemp, the fibrous material from low-TCH strains of the Cannabis plant, has uses ranging from food to medicine, clothing, paper, and even construction. When hemp is combined with lime, you get a carbon-negative building material with greater flexibility and only 15 percent of the density of traditional concrete. Called hempcrete, this insulating and moisture regulating mixture is hard to come by in the United States, as the Cannabis plant is currently federally prohibited from being used in industrial production.
Hempcrete lacks the compressive strength of traditional concrete, however, and requires an additional framing element to support vertical loads – but its other properties would make it an attractive alternative building material, if not for hemp’s legal status.