It sounds like a headline from the future: the weekend before Thanksgiving, a bulldozer came for the first example of a printed home that was supposed to help the housing crisis in the city of Muscatine. Fortunately, it hadn’t been completed and sold yet.
Printing of this first house began in May 2023, and nine more were to be completed by the end of the year. The house was being constructed from Hempcrete, which a biocomposite of hemp hurds, and either lime, sand, or pozzolans that is used in Europe and Canada.
In tests, the hempcrete was capable of reaching a compressive strength of 6,000 to 8,000 PSI. But in actuality, it didn’t even meet the 5,000 PSI minimum required for the project.
The project is a collaborative effort between the Community Federation of Greater Muscatine (CFGM), Muscatine Community College, and Alquist 3D. Although not as proven a printing material as traditional concrete, Hempcrete was chosen in part because Muscatine Community College has Iowa’s only hemp program. One of the goals for the project was to have students research hemp’s properties, and launch a 3D printed construction curriculum in partnership with Alquist 3D.