3D-printed houses poised to go mainstream



Joann Muller
Mon, October 25, 2021

3D-printed cement houses are about to take off, offering a cheaper, more efficient way to provide homes for those who need them — as long as they can be built in ways that don't worsen climate change.

Why it matters: Developers of 3D-printed homes think they can take on multiple challenges: the affordable housing crisis, the shortage of skilled labor and rising material costs.

At least one is also adapting its technology to mass-produce homes without releasing too much carbon into the atmosphere.

What's happening: A handful of companies are erecting new subdivisions featuring 3D-printed houses.

Instead of conventional materials like steel, aluminum and lumber, 3D-printed structures are built by a robot squeezing a cement mixture out of a nozzle, layer upon layer, like a soft swirl ice cream cone.

It's the same additive manufacturing process used to make everything from dental implants to airplane parts — just on a much, much larger scale.

Only a few dozen 3D-printed homes have been built, or proposed, so far in the U.S., but that's about to change.

What they're saying: "After years of R&D, the market is nearing a tipping point as companies are moving beyond pilots and demonstration projects," according to market researchers at Guidehouse Industries.

"Considering current tight construction margins and labor shortages, 3D printing has the potential to revolutionize construction," they wrote, adding that widespread adoption is still years away.

Where it stands: Among the early pioneers is Austin, Texas-based ICON, which has delivered more than two dozen 3D-printed homes in the U.S. and Mexico and just raised $207 million to expand.

The company prints homes on-site, using its Vulcan construction system, with a gantry-mounted nozzle that lays down the house's walls, layer by layer.

Its proprietary Lavacrete cement mix is "a closely guarded secret" that combines ordinary Portland cement with "advanced additives" for structural integrity.

The homes are designed to be energy-efficient and withstand extreme weather and earthquakes, ICON says.

Mighty Buildings, a competitor, offers an alternative that focuses equally on the housing and climate crises.

The San Francisco-based company aims to become carbon neutral by 2028 — more than two decades ahead of the rest of the construction industry.

"We make houses as tools to fight climate change," co-founder Sam Ruben tells Axios.

How it works: Mighty Buildings uses 3D printing to produce modular panels in a factory, then delivers them to the lot for assembly.

The panels are a synthetic stone made from a polymer composite and include a steel frame, insulation and even gypsum board, or drywall, for the interior walls.

With robotic tools, the panels can be milled for the desired look, like stucco or siding.

Mighty Buildings started out printing "accessory dwelling units" — small guesthouses that are one answer to the housing shortage.

It's now marketing 3D-printed home kits — similar to the Sears catalog's mail-order home kits in the early 20th century — for $349,000.

It is also partnering with a developer, Palari Group, to build two subdivisions in California.

Their 15-unit neighborhood in Rancho Mirage, near Palm Springs, will be "the first 3D-printed, net-zero-energy community," the companies say.

With built-in solar panels and storage batteries on-site, homeowners won't spend a nickel on electricity, says Ruben.

Yes, but: Construction is a major contributor to climate change. It takes enormous amounts of energy to produce cement, a key ingredient in concrete, the ubiquitous foundation of our built world.

The cement industry alone is responsible for 8% of global CO2 emissions, according to the World Wildlife Fund.

That's one reason Mighty Buildings is partnering with a company that figured out how to trap those emissions in an innovative low-carbon cement.

The bottom line: It's too early to say whether 3D-printed houses will meet the test of time, says Henry D'Esposito, construction research lead at JLL, a real estate services firm.

"We've never seen one of these at 20, 30, 40 years old," he tells Axios.

Like this article? Get more from Axios and subscribe to Axios Markets for free.