A one-of-a-kind 3D printed house mixes concrete and wood
Casting layers of concrete like rows of toothpaste, an industrial-sized 3D printer this week continued to add a second story to a Houston home that will be the first multi-story printed structure in the United States.
In addition to this achievement, the designers Leslie Lok and Sasa Zivkovicassistant professors of architecture at the College of Architecture, Art and Urbanism (AAP) and co-directors of the HANNAH design officesay the two-story single-family home demonstrates innovative construction processes that can be extended to multi-family and mixed-use developments, helping to address housing shortages.
Their hybrid design, the first of its kind, connects structural elements composed of 3D-printed concrete to a conventional wood frame representative of most American residential construction. The combination shows how each material can be used where it works best, with minimal waste, to create buildings that are efficient, resistant to increasingly intense weather events and potentially more affordable.
“Our hybrid building approach creates a building system that is structurally efficient, easily repeatable, and materially responsive,” Lok said. “The project also highlights the exciting design potential of mass-customized architectural components to meet owners’ needs and to simplify the integration of building systems.”
Zivkovic added, “These design efforts aim to increase the impact, applicability, sustainability, and cost-effectiveness of 3D printing for future residential and multi-family buildings in the United States.”
On September 12, members of the media were invited to observe the progress of the printing of the three-bedroom, three-bathroom home which will also include a two-car garage and a 40-foot chimney – making the home l one of the tallest structures printed on Date.
The house is built in partnership with PERI 3D Construction, which has produced six 3D printed structures in the United States and Europe; CIVE, a Houston-based engineering and design-build contractor; and other building industry partners. The project team continues to seek industry collaborators and sponsors.
For Lok, who runs the Rural and Urban Buildings Innovation Lab at AAP, and Zivkovic, who runs the Robotic Construction Lab, the project is the latest to emerge from years of research into the potential of 3D printing to enable “mass customization” without driving up costs. They have already experimented with a hybrid design using 3D printed concrete and recycled wood for the Ashen Cabin project in upstate New York. Lok’s HoloWall installation on the Arts Quad explored customization using non-uniform building materials and digital modeling tools. Zivkovic’s past research involves developing new methods of printing concrete and robotically fabricated wooden components.
The 4,000 square foot Houston project is progressing to a larger scale, which will require another American “first” – relocation of the large gantry supporting the printer, which measures approximately 60 feet long, 30 feet wide and 30 feet wide. high, to complete the structure.
Across various systems – from spray foam insulation to a heating, ventilation and air conditioning system more common to commercial buildings – the designers say the home incorporates design and construction processes well suited to multi-family developments that will be needed to increase housing capacity in fast-growing cities like Houston.
The designers said their approach could also speed up construction times and reduce costs because concrete printers can be operated by as few as three or four people. It also minimizes waste, as the material can be mixed on demand and printed only for structurally important sections, and can integrate timber framing more efficiently into a modular design.
“Besides printing technology, integrating printing with building design and construction materials, and streamlining the construction process are important aspects in realizing such a project,” Zivkovic said. . “We are using this project to demonstrate how 3D printing is not only market-ready, but also capable of building well-designed, high-performance architecture.”
For the Houston home, printed material is sourced locally and uses low-carbon-footprint cement, a mixture that can include fly ash, slag and other industrial by-products. Designers are collaborating with colleagues at the College of Engineering on research related to environmentally friendly building materials, including concrete’s potential to store methane, a potent greenhouse gas. Timber framing, on the other hand, is a renewable resource but is often the product of forest monocultures and can be transported over long distances.
Lok and Zivkoviv said the Houston home optimizes the use of both materials while making better use of their design potential than many structures limited to just one.
“There’s no design there,” Lok said, “that thinks of multi-family housing using those two systems together.”