Icon—a winner of Fast Company’s 2020 World Changing Ideas Awards—has built a 3D printer so large it can print the walls of a house in 24 hours.
Later this year, in a remote part of Southern Mexico, 50 families will move into the world’s first 3D-printed community. And on the outskirts of Austin, Texas, six people who were formerly homeless will move into small 3D-printed homes this May. The two projects are the first large-scale proof that 3D printing technology could be a viable way to quickly build affordable housing.
“If we want to get our hands on the global housing crisis, not across hundreds of years but in tens of years, we need a highly scalable solution, which 3D printing will be,” says Jason Ballard, cofounder and CEO of Icon, the company that created the massive 3D printer that built the new homes. The company is the winner of the general excellence category in Fast Company’s 2020 World Changing Ideas Awards.
The startup’s printer, at 33 feet long, works like a giant version of desktop 3D printers, squirting out a custom concrete mixture in layers like frosting on a cake. The process builds the walls of the house, with other parts, including the roof and windows, added later. “The wall system is typically the most laborious, expensive, error-ridden, wasteful part of the construction process,” Ballard says. The system combines the installation of multiple components, including insulation, into one process, and the company’s engineers are now experimenting with adding plumbing and electrical wiring into the 3D print.
The company partnered with New Story, a nonprofit focused on finding better ways to build affordable housing, as it developed the technology. In Mexico, the team is building homes for some of the poorest residents in a rural area near the city of Nacajuca. The homes will be donated to families who are currently living in makeshift shacks that flood every time there’s heavy rain and that would be likely to collapse in an earthquake. While the shacks had single rooms—with a patchwork of scraps over holes on walls and roofs—the new houses have two bedrooms, a kitchen, and a living room. For most families, it will be the first time they have access to indoor plumbing and electricity.
The process made it faster to build a house; the walls can be printed in 24 hours, meaning that total construction time for the whole house may be cut in half. In areas where there’s a shortage of construction workers, it can help fill that gap. The reduction in labor, combined with affordable materials, also makes it less expensive to build. The materials are more rugged than standard construction in the area and better able to withstand disasters like hurricanes. “Almost all other approaches to building use inherently nonresilient material that you have to mitigate with treatments or coatings or extra cost,” he says. “But we’re starting with a resilient material.” (The material, called Lavacrete, is a custom mix that can flow easily but can also set precisely as the machine pumps it out.)
The first houses in Mexico were completed in December 2019; in Texas, the first few smaller homes were finished in March. The company continues to develop the technology. On the site near Austin, it attempted printing multiple homes at once. “We designed an experiment: What if we line up the printer and print three houses at a time? Would that help us go even faster and reduce costs even further? The answer turns out to be yes, absolutely. That’s another subtle way that we’re able to attack cost, by being more efficient with our materials use.”
The company hasn’t yet shared manufacturing costs since the technology is still at an early stage. But the goal, Ballard says, is to have a system that makes it possible for anyone to download a design and print a house in half the time of regular construction—at half the cost.
[Photos: courtesy Icon]