A 3D-printed home builder demolished a house before it was complete. Here's why.

• A 3D-printed home in Iowa was demolished before it could be completed.
• Construction 3D-printing startups say they could build homes faster and cheaper than traditional methods — but when?
• Alquist's CEO says the budding construction-tech industry is facing issues like expensive materials.

If construction 3D printing startups can fulfill their promise of creating faster, cheaper, and better homes, the US homebuilding industry could be upended and changed for the better.

The question is: What will it take to achieve this?

Over the last few years, 3D-printed projects that seemed impossible only a decade ago now exist around the US as proof of the tech's capabilities. And progress is happening fast: In 2018, construction-tech startup Icon said it had built the country's first permitted 3D-printed dwelling, a 350-square-foot unit. Five years later, the Texas-based company is now working with construction giant Lennar to create the world's largest community of printed homes.

In Virginia, Alquist built a Habitat for Humanity home using a printer. And in Maine, the University of Maine printed a fully recyclable tiny house.

These budding startups are making big promises amid the US' ongoing housing affordability crisis

Compared to traditional homebuilding methods, 3D printing proponents say the tech can build high-quality natural disaster-resistant homes cheaper and faster while reducing waste and labor.

If startups can fulfill this promise, the growing industry could increase Americans' access to affordable homes. But to get there, companies paving the way will have to reckon with several pain points.

Printing a home isn't as easy as copy-paste

Like the mass implementation of any new tech, startups spearheading this new market could face an inevitable learning curve plagued by expensive materials, varying construction requirements, and a still-developing workforce.

In the fall, Alquist began building a set of 10 homes in Muscatine, Iowa. The first of these, a roughly $300,000 1,300-square-foot house, would have had walls built using RIC Technology's robotic arm printer and Quikrete's printing mix.

This development was nothing new for Alquist — the startup already has several successful projects, including the Habitat for Humanity home. Despite this experience, the company hit a roadblock in late November: It decided to demolish the first of these 10 homes before it could be completed.

The three-bedroom unit didn't meet the 5,000-psi (pound-per-square-inch) target, igniting structural engineers' concerns about the strength of the printing mix, Zachary Mannheimer, the startup's founder and chair, told Business Insider.

He believes the unit would've been structurally sound if it had been finished. The company previously used this same material to successfully build two homes, but "there are different requirements, climates, and structural engineers everywhere you go," Mannheimer said.

So instead of continuing discussions between the engineers and material suppliers, Alquist decided to demolish the home. The fate of the development is now unknown.

"We're inventing a brand new industry," Mannheimer said. "There are successes and mistakes made during the process that everybody's going through."

Companies at the forefront of this are sorting through complicated moving parts

The cost of using printers is currently equal to or a bit higher than conventional construction methods, Philip Lund-Nielsen, cofounder of 3D printer manufacturer COBOD, told Business Insider in October. He believes this price will drop as the tech continues to advance, likening its progression to the history of mobile phones.

For all printed homes to become significantly cheaper than their traditionally built counterparts, Alquist's founder says the industry needs to make four changes: better printing efficiency, decreased material costs, increased workforce development, and the ability to print several homes at a time.

The materials and equipment needed on construction 3D printing sites have sky-high price tags. Many printing mixes cost more than everyday concrete at an average of about $800 to $900 a yard, Alquist's founder said.

But there's no use for a printing mix without a printer. If you want to buy one of the most popular ones on the market, COBOD's BOD2, it'll cost at least $500,000 to $600,000.

The shipping fee for a printing system of this size then becomes another financial beast. So does the workforce training needed to mass implement this tech. (After all, not everyone in construction knows how to use a 3D printer.)

And when everything has been acquired, there could still be on-site issues related to the equipment, weather, material, or labor.

However, Alquist's founder says the company is working on solutions to many of these glaring issues, and "to have an industry that's only a few years old, almost there, is pretty amazing."

The startup is now developing a less expensive "non-cementitious" printing mix that could be ready in the spring of 2024. Next year, Alquist also plans to partner with more companies "to help them with an inexpensive pathway" into the market, Mannheimer said. "If you're not using local crew and material, there's virtually no way to make printing houses as affordable as everybody wants."

Despite Alquist's recent setback, Mannheimer seems hopeful for the future of the industry: "I think 2024 is going to be a pretty amazing year for the industry. Next summer, I think you're going to see this thing begin to take off, not just for us, but for all the companies."