Hempcrete Homes Get the Green Light in the United States
The International Code Council (ICC) has approved the construction of homes in the United States using hempcrete, a building material made from a mixture of lime and the woody core of hemp stalks.
Hemp Growers Achieve Approval for Cannabis-Based Building Material
In 2022, demand for hempcrete surged across Europe. According to George Popov, a client of the Canxchange marketplace where cannabis products are sold, this building material is now difficult to find due to low supply. Hempcrete has become extremely popular primarily because of its affordability—a ton of the mixture costs between 200 and 450 euros (approximately $215 to $485).
However, in the US, hempcrete was not previously included in the list of approved building materials and therefore was not widely used. To address this, the US Hemp Building Association petitioned the ICC to approve the use of hempcrete. The agency granted the request, which means that starting in 2023, hempcrete can be used in the construction of single-family and two-family homes, as well as townhouses, throughout the United States.
Architect Ana Konopitskaya from Pennsylvania commented on the news: “From an architect’s perspective, including hempcrete in the list of approved materials is extremely important. This will allow architects like me to make this product a part of the construction industry in all American municipalities.”
The Advantages of Hempcrete
Hempcrete is very easy to produce. To make it, lime (which acts as a binder) is mixed with hemp hurds in a 1:4 ratio. By adding one part water and mixing thoroughly, you get a liquid mixture that can be poured into molds to create blocks used for various structures or for insulation.
Builders have embraced hempcrete because it:
- Is fire-resistant
- Contains no harmful chemicals
- Retains heat well and withstands temperature fluctuations
- Efficiently absorbs and releases moisture
- Is highly resistant to insects
- Requires less water to mix than traditional concrete
Hempcrete is considered a carbon-negative material because hemp absorbs more carbon dioxide during its growth than is released during its production. In contrast, traditional concrete accounts for 8% of global CO2 emissions. Switching to hemp-based concrete could significantly reduce carbon emissions.