Although mud and daub type building structures date back thousands of years, interest in concrete made from plant materials has increased due to the interest in sustainable architecture.
Research into more sustainable buildings materials have led to the development of bio-composite concrete of hemp and lime, which has been registered in the United States as Tradical Hempcrete® by American Lime Technology Products company.
This green product is also sold as precast walls with structural framing. The hemp lime product alone had issues with fire safety, rotting under wet conditions, and the lack of ability to perform as a standalone structure due to its poor load-bearing qualities.
Different framing structures have been introduced worldwide to improve the capacity of the building material to be used in larger buildings, although ironically these high rise buildings have been found to be less energy efficient which seems to defeat the purpose of green building.
Hemp or bamboo stalks as the structural frame combined with the hemp/lime concrete mixture are the currently preferred construction materials, and are used by companies such as Hemp Architecture in England, described in an Architectural Review article on alternative building materials.
Growing hemp for construction purposes was never criminalized in in Europe, and hemp-constructed homes as well as businesses have flourished in France and the United Kingdom
Other building projects have continued in the United States, though custom homes using hemp based products such as James Savage’s home in Stuveysant, NY are the exception rather than the rule.
The main impasse to American hemp-based construction was growing hemp was not legal in the United States until recently, and the majority of hemp construction products are imported from Canada. Although these products are fire and pest resistant, as well as economically friendly, the main appeal may be the appeal of the drug culture stigma more than the practicality of the building materials.
