The first 3D-printed house in Michigan is on the market. Asking price: $224,500.
The tidy cottage a few blocks from the Belle Isle Bridge is hard to miss.
It’s brand new and modest — just 988 square feet — in a neighborhood of aging houses that reflect the outsized wealth of mid-century Detroit.
Its walls were squeezed like toothpaste out of a nozzle on a robotic arm, one thin layer at a time.
And it’s priced far above the city’s estimated average sale price of $82,000.
Is this an expensive oddity, or the first shot in a homebuilding revolution that will drive down housing costs and change the way our homes look and feel?
Citizen Robotics, the nonprofit behind the project, believes that automation will eventually drive down home prices if the technology becomes widespread.
That’s a big “if,” but we don’t want to write off any attempt to tackle Detroit’s housing affordability problem, even when the fix seems far off. Plus this spot looks kinda cozy! Here’s what you need to know.
How Citizen Robotics prints a house
The company’s 10-foot robotic arm, which it bought secondhand, sits in the center of a warehouse in Southwest Detroit. A few feet away, a tower of machinery sits ready to mix a special concrete blend and pump it to the tip of the robotic arm.
The walls of a 3D-printed house start as a two-dimensional shape and grow upward. A wall might begin as a rectangle with rounded corners.
To build the wall, the robotic arm repeatedly traces this shape. Following a digital blueprint, it adds another narrow bead of wet concrete with each pass, leaving gaps for electrical outlets. The specially formulated material dries quickly, and the wall rises 10 to 15 millimeters with every new layer. (Fancier machines can speed up the process by adding new layers to several walls at once.)
Completed wall sections are shipped to the new home site, where they are connected. The roof, plumbing and electrical wiring are added through more conventional methods by tradespeople.
Why 3D-printed houses could be the future
One word: Cost.
Citizen Robotics, the nonprofit that built the new cottage, envisions a world where robots construct the walls of a house from a digital plan in a matter of days. Only a handful of workers would be required to operate the equipment and double-check quality.
Faster production and fewer workers means lower building expenses — and, hopefully, lower home prices.
Cost is what’s fueling the hype train, even as fans of 3D printing see many more benefits — from new design possibilities to reduced environmental impact.
Gov. Gretchen Whitmer, whose administration funded much of the Detroit project, called it a “cutting-edge endeavor with the potential to change the affordable, attainable housing landscape in Michigan.”
A developer in Austin, Texas, secured funding to construct 100 homes in the world’s first 3D-printed neighborhood. Dubai is prioritizing 3D-printed concrete in new construction. Montana adopted the method into its building code. NASA held a design competition for houses that could be 3D printed on Earth or Mars. (The winner looks like a lava lamp.)
Cost isn’t the only benefit, said Evelyn Woodman, Citizen Robotics’ co-founder and communications director, adding that 3D-printed walls are stronger, less fire-prone, less wasteful and easier to insulate than typical wood construction.
Concrete is carbon-intensive and is viewed as a tough-to-solve climate change problem, but 3D-printed homes use it more efficiently than other concrete-based construction, and some engineers say it could allow for new concrete mixtures that would reduce the material’s global carbon footprint.
The method also makes design features like curved walls more accessible.
Woodman gestured to a wavy wall in the company’s warehouse. In conventional building methods, “it would be handcrafted. But for us, (with a 3D printer)… it’s trivial.”
Why 3D-printed houses might not catch on
“Printed” housing seems unlikely to stick — much less make a difference in Detroit — unless the cost is at least competitive with standard building methods.
Michigan’s first 3D-printed home doesn’t offer proof of concept on that front. Building it took a year and cost about $36,000 more than the $242,500 asking price.
The Michigan Housing Development Authority, which funded the project with a mix of grants and loans, set the final price.
This kind of construction needs scale to achieve cost savings — think of the 100-home development in Austin.
“It’s a fool’s errand to build just one house,” Woodman said.
A much larger project wouldn’t just give the company more chances to refine their methods. It could also provide enough economic heft to get the attention of tradespeople who are needed to finish the house, and who rely on big jobs for higher, steadier wages.
Once they had the method down, the walls of the house were printed in five days with two people monitoring the machinery.
“A lot of the past year wasn’t construction time,” Woodman said. “It was us waiting around, pleading with tradespeople to give us a quote.”
The tradespeople who weren’t answering calls from Citizens Robotics may have had an issue with the very idea of 3D-printed housing.
This technology is a form of automation that could eliminate jobs and concentrate wealth in the hands of the technology’s owners. Society — from politicians and voters to workers and corporations — is responsible for making sure productivity gains from 3D printing are equitably distributed.
The list of barriers goes on. Michigan’s building code doesn’t allow load-bearing walls that are 3D printed. Citizen Robotics reinforced their walls with concrete columns, which added to construction costs. Getting the state code changed — which happened last year in Montana — would be expensive and time-consuming, said Fernando Bales, build lab manager for Citizen Robotics.
Like any technology innovator, Citizen Robotics is trying to create the chicken and the egg at the same time. 3D-printed homes won’t be affordable unless they’re widespread, and might not become widespread if they’re not affordable.
“The price point will come down over time — if you reach adoption,” Woodman said.
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