Key takeaways
- Cole Klein Builders and HiveAsmbld are developing Houston's first 3D-printed housing development with 80 affordable single-family homes priced in the $200,000s.
- The hybrid construction model uses a robotic arm to print cement walls for the first floor before traditional stick-building completes the upper level.
- The proprietary cement mix developed by Eco Materials Technologies dries in minutes and has 90% lower carbon emissions than traditional Portland cement.
About 20 minutes south of downtown Houston, just off Highway 288, lies roughly 10 football fields’ worth of gravel. At the back of the lot, new condo buildings are nearly finished. Nearby, cleared parcels and signs for LGI Homes and D.R. Horton developments line Martindale Road.
But turning off into a development called Zuri Gardens, home to 13 acres of gravel, a bit of imagination is required to envision how the barren land will soon become the city's first-of-its-kind housing.
In about 18 months, the lot is expected to be the site of 80 hybrid 3D-printed homes — affordable, single-family residences that would make Zuri Gardens one of the country's largest 3D-printed housing developments.
On Thursday, at a groundbreaking ceremony for the development, Cole Klein Builders and HiveAsmbld revved up the robotic arm responsible for building the homes’ first levels. The homes will then be finished with human framers through traditional stick building and sold in the mid-to-high-$200,000s.
It’s called a hybrid model for using both the innovative robotic building technique cropping up around the country and traditional construction for the second floor.
In an industry known for its slow adoption of technology, 3D printing has exploded as a means to faster home delivery and more affordable homeownership.
The first owner-occupied 3D-printed home was built in 2021 by Alquist 3D and Habitat for Humanity. The largest development in the country, consisting of 100 homes printed by Icon and developed in partnership with major homebuilder Lennar, is just 186 miles from Zuri Gardens. It wrapped up in March.
Developer Vanessa Cole of Cole Klein Builders described the Zuri Gardens homes as “modern farmhouse” spanning about 1,360 square feet with two bedrooms, two and one-half bathrooms, an office and a covered outdoor patio.
The printed first floor is a means to transition the market into the new technology and bodes well for homeowners whenever flooding in Houston happens, protecting the first floor entirely, said Cole.
“You just wipe your walls. You may have to replace some furniture, but then you go back to your standard of living,” she told Homes.com in an interview.
The robotic arm pushes cement out to create a hollow shell, which is then filled with another cement mix that serves as insulation and encloses the mechanicals, plumbing and electrical system. As the first layers were poured at Zuri Gardens, construction workers built a rebar structure to support later additions.
A solution is in the works to make remodeling easier, according to HiveAsmbld, but for now, the system limits what buyers can do to the homes.
“The beauty of an indestructible structure is that it’s indestructible,” Robert Spiegel, chief development officer at HiveAsmbld, told Homes.com in an interview. “Future renovations are difficult. They’re not impossible.”
That first floor won’t require sheetrock inside like a traditional home or siding and weatherproofing on the exterior, either. The walls of cement — that dry with ridges revealing its printed technique — serve both functions. It can be painted, plastered or drilled into to hang artwork like any old wall, though.
As for permitting and inspections, the homes are set to be treated as if they were built with cinder blocks.
Affordability and resistant housing meet
Zuri Gardens utilizes $1.8 million in tax increment reinvestment zone funding from the city of Houston to offer prices $100,000 less than the national median price of a single-family home.
That investment requires the project to follow affordable housing guidelines, with lenders also offering up to $125,000 in down payment and closing cost assistance for eligible buyers making less than 120% of the area median income.
Alongside the attainably priced trait of 3D printing, a component of many large printed developments, Zuri Gardens’ technology offers the same features that most cement-based homes do: resistance to extreme weather, pests, rot, mold, fire, and, most pertinent to Houston, flooding.
Tim Lankau, founder and co-CEO of HiveAsmbld, told the groundbreaking ceremony crowd that he calls the structures literal "forever houses.” The cement was noted to have superior strength — the average pressure resistance for a street would be about 4,000 PSI compared to Zuri Gardens’ 6,500 PSI.
“Archaeologists are going to dig up these houses in 1,000 years and wonder what they were,” Lankau said. “And they’ll plan out what Houston looked like based on these 6,500 PSI concrete walls that no bug can eat, no storm can blow over, no water can damage.”
The resistance to flooding is a big bonus for Houston homebuyers, agent Maria Bonilla told Homes.com in an interview. Sales have begun, and two buyers have already started applying for the unprinted properties.
“They don’t want stress. They want comfort, and knowing that it would never flood … they don’t have to worry about that,” Bonilla said. “It’s also energy efficient. We’re seeing that it’s usually $50 or less a month on utilities, even in the summer.”
The technology behind this 3D-printed development
What makes Zuri Gardens' technology different from its predecessors, the builders say, is its proprietary cement, developed by Eco Materials Technologies, that includes more additives.
As the robot spits out wet cement layer upon layer, the material must dry in minutes to support the layers being added, according to HiveAsmbld co-CEO and inventor Ethan Wong. That's significantly faster than the days-long drying period for other concrete structures, such as sidewalks.
The mix is also touted as the most environmentally responsible and cost-friendly 3D-printed material for its low carbon footprint. The carbon use is 90% lower than what's known as Portland cement, the most commonly used type, according to Eco Materials Technologies.
“We want to build these homes and 100 years from now, we want kids taking their first steps in it and the next generation and next generation,” said HiveAsmbld co-CEO Lankau. “That’s concrete. That’s why Rome still looks like Rome.”