[Image above] The TECLA home by Mario Cucinella Architects and WASP is made using local soil instead of concrete. Credit: Sky News, YouTube
In recent years, governments around the world have started giving more attention to the long simmering affordable housing crisis, which affects both developed and developing countries alike.
The United Nations estimates that 3 billion people, or 40% of the world’s population, will be in need of accessible and affordable residences by 2030. And in the past year, the coronavirus pandemic has only worsened existing housing inequality.
In the past few years, several companies have envisioned using 3D printing to construct affordable homes and communities quickly and at low cost. For example, Texas-based construction company ICON partnered with charity New Story to build a 3D-printed neighborhood in Mexico for local families living in extreme poverty. This year, New York-based construction firm SQ4D listed its first 3D-printed demo house in Riverhead, New York, for 50% below the cost of comparable newly constructed homes in the area.
While the intentions of these companies are noble, many of them rely on using concrete or synthetic materials like plastic to print the homes—materials not always readily available in all parts of the world, especially underserved rural areas. Designing a 3D printing process that uses local materials would help expand the ability to build in some of these underserved areas.
A recent collaboration headed by Italian architect Mario Cucinella aims to design just such a process. Cucinella is a global leader in sustainable architectural practices, and he views sustainability as integral to all parts of the building process. “When we talk about sustainability, I think we need to also think about the process of construction, because construction processes are very high-consuming and (make) high emissions of CO2 (carbon dioxide),” he says in a CNN article.
His architectural company, Mario Cucinella Architects, recently partnered with Italian 3D printer manufacturer WASP to look into 3D printing homes using local materials. Their TECLA project, the name of which is derived both from writer Italo Calvino’s fictional city of Thekla as well as an amalgamation of “technology” and “clay,” involves using Crane WASP printers to 3D print homes out of local soil mixed with water, fibers from rice husks, and a binder.
Cucinella and WASP recently finished the first TECLA prototype, a 60-square-meter (645-square-foot) home located in Bologna, Italy, where Mario Cucinella Architects is based. The fabrication process took longer than comparable projects using quick-drying concrete due to the clay mixture needing more time to dry, sometimes weeks depending on climate. However, the flexibility of using available soil means “You can build this kind of house in many more places when you are not dependent on some specific product,” Cucinella says in the CNN article.
Though Cucinella sees 3D printing with natural materials as an important tool for tackling the housing crisis as well as achieving climate neutrality, he notes that it is not the solution in all situations. For example, the overpopulation crisis in major metropolitan areas, such as in China, would not be solved by small clay buildings. However, “I think the revolution of 3D printing is to give people a degree of freedom in how to do things, without being connected to a big, professional industry,” he says.
See part of the TECLA building process in the video below. The TECLA prototype is currently undergoing structural and thermal performance testing before attempts are made to scale-up the process.