The small plastic models sat on the table with the 3D printer while the large machine trundled to life in the Jefferson neighborhood.

Instead of plastic, the machine was using a specific cement mix to create the walls for 1,200-square-foot, three bedroom and two bathroom house compared to the miniature.

Corrine Mann, 32, excitedly walked around the construction site of her home and spoke with onlookers, Habitat for Humanity Peninsula and Greater Williamsburg staff and Alquist 3D builders.

“I think it’s going to be the future,” said Mann, a lab technician and single mother with an 11-year-old daughter named Aubrey.

3D printing a home is not too different from a typical build for a house, said Zachary Mannheimer, founder and CEO of Alquist 3D.

“Really the only difference between a 3D printed home and a regular home is the walls are made out of concrete instead of wood — that’s it,” he said.

The advantages are less expensive materials and less labor for building the walls for the home, which result in lower costs, Mannheimer said. For example, 3D printing of the walls would be done within 20 to 25 hours. Additionally, the homes can withstand most major storms, don’t burn and use 50% less energy than traditional stick-build homes, he said.

“But other than the walls, everything’s the same,” Mannheimer said.

That means trade work is still needed, such as plumbing and HVAC. Mannheimer said 3D printing could attract more workers to the construction industry because of the use of a large machine and the advanced nature of the technology throughout the process.

For a 3D printed home, the foundation is poured as normal, then the printer arrives, Mannheimer said. The raw material then goes into a silo, is mixed with water and then pumped through a hose to the nozzle of the machine, which goes around layer by layer to print the home based on a design programmed into the machine, he said.

Technically, the machine could use any concrete, but Mannheimer said they use a specialized mix for their home printer that can withstand 10,000 PSI, which is almost four times as strong as traditional concrete.

Though the mix is cheaper than lumber today, sourcing mix components more locally would be a way to bring down the price further, he said.

“Something we’re looking at heavily here is using fly coal ash from Appalachia in the mix, which solves two problems,” Mannheimer said. “One, it’s low-cost and we can use it in the mix. And two, there’s a big problem with coal ash in Appalachia; there’s millions of pounds just sitting there, and nobody knows what to do with it. So this would help with an environmental concern as well.”

Janet Green, executive director of the Habitat chapter, said this is the second 3D printed home Habitat for Humanity is buying, and next to Mann’s house, another home will be 3D printed by Alquist with help from Habitat staff.

“Any means that we can continue building more affordable housing is so critical,” Green said. “And if we can do it faster, cheaper, safer, why wouldn’t we try? So I like to say it’s another tool in our toolbox for affordable housing.”

Mann, who grew up in Hampton, said she has talked with friends and neighbors about how expensive the region has grown over the years and was shocked to see prices when she was looking for a place to live in Newport News.

“It’s crazy to hear some stories,” she said.

For one place, she’d need to raise her credit score and make more money to live there. So, she began working on finances as she applied to Habitat for Humanity and was accepted for the group’s usual 30-year, no interest loan to buy the 3D printed home.

Green said the 3D printed homes are up to 15% less expensive to build.

“If we can build these houses faster and have more people have the stability of affordable housing, that’s a win-win for our community,” Green said.

In addition, the group saves time in construction.

“We’re hoping to shave off at least six weeks with the 3D house,” Green said. “Because it’s still a new technology, we’re going slower than we normally would to make sure that everything is done consistently.”

Last year, the group printed its first 3D home in the summer, and by December, a family moved into the first Habitat for Humanity 3D printed home in James City County.

Mann said she enjoyed watching the home come together in real time as the symphony of machinery made its rounds and the home’s walls crept up toward the sun.

When people are puzzled that she will be living in a 3D printed house, Mann tells them to look it up on the internet and learn more — just like she did. Mann hopes they also came away as amazed as she was.

“I feel really good about it,” she said. “And I’m glad I made this decision.”