The 3D-concrete printing phase has been completed on Los Angeles County’s first approved 3D-printed home, marking a milestone for both the project and the resident who lost her home in the 2025 Eaton Fire.
The project is being led PCI Builders in collaboration with RIC Robotics and Stone River Dynamics. (You may recall RIC from our previous coverage, including its 20-foot-tall Zyrex construction robot and 3D printing a 5,000-square-foot Walmart expansion in seven days.)
The concrete wall system provides an alternative to conventional wood-framed construction and highlights the broader potential of 3D concrete printing in wildfire-prone areas.
The 3D-printing process allows material to be placed precisely where it is needed, reducing formwork, excess material, construction waste and the on-site footprint associated with conventional concrete construction. It can also support advanced material formulations, including fiber reinforcement and geopolymer-based mixes, that may enhance durability, structural performance and thermal behavior.
RIC Robotics and Stone River Dynamics both printed separate portions of the home. To watch the home printing in action, check out the video from Stone River Dynamics below.
Plumbing and electrical work are now progressing through inspection, and roof trusses are on site as construction continues, according to RIC Robotics. The completed home will also incorporate Sonic Fire Tech’s waterless, sound-based fire-suppression technology as part of a layered approach to fire protection.
Powered by“Losing my home in the Eaton Fire was devastating, but I knew I wanted to rebuild in a way that felt safer and more forward-looking,” said homeowner Cindy Lopez. “This home represents more than my own recovery, I hope it helps other families see what is possible while encouraging local governments to recognize and invest in 3D-concrete printing as a meaningful option for communities facing increasing wildfire risk.”
Lopez’s home was one of more than 9,000 structures in the community destroyed by the Eaton Fire.
“When Cindy lost her home, our goal was not simply to replace what had been there, but to help her rebuild with greater confidence in the future,” said Allison Allain, founder and CEO of PCI Builders. “By bringing together thoughtful design and 3D-concrete printing, we are showing that building for resilience does not mean sacrificing design, character or individuality."
RIC Robotics and Stone River Dynamics worked to ensure the robotic 3D concrete printer could navigate the home’s complex Spanish-style architecture with intricate features, including arched windows, sills and headers.
"This project demanded creativity, patience and a willingness to solve challenges in real time," said Ziyou Xu, Founder of RIC Robotics. “Our team was committed to preserving the design Cindy envisioned, further demonstrating that robotic construction can support architectural expression rather than limit it."
Stone River’s Sidekick 3D concrete printer features a compact footprint and lightweight design, making it easy to maneuver around the jobsite and precise enough for delicate sections.
RIC Robotics calls its RIC-M1 Robot its “most popular model for single-story residential construction — and one of the most cost-efficient full-scale house-printing solutions on the market.” It has a build envelope of 29.5 feet by 19.7 feet by 9.8 feet and a maximum speed of 1.9 inches per second.
The team established a construction approach that was technically feasible and acceptable to Los Angeles County, while navigating constructability, permitting and inspection requirements for an emerging residential building method. The project serves as a real-world case study for the advanced technology and could help inform future 3D concrete-printed projects in Altadena and other communities.
