Startup Stories: Building Houses with Printers
A conversation with Nick Callegari ’25, whose startup Impact3D has reimagined the 3D printer as a tool to create more affordable and sustainable housing.
In this series, Karen Guzman talks to student and alumni entrepreneurs about how they are making an impact with their startups.
Founder: Nick Callegari ’25
Venture: Impact3D is developing a construction 3D printer that creates sustainable, affordable housing materials. Functioning without a gantry framing structure, the printer uses upcycled materials to create complete walls with electrical harnessing, plumbing, and insulation.
What was the moment when you had the idea for this startup?
I left my role as a mechanical design engineer at SpaceX to come to SOM and start a venture in the social impact space, but at first I didn’t know what to focus on. I wanted to use my engineering skills to tackle some of the world’s most pressing problems. Participating in TSAI City’s Climate Innovation Intensive piqued my curiosity about construction methods. I later discovered construction 3D printers that use polylactic acid (PLA) filaments, which are similar to printers I had used in previous engineering roles. These devices have so much potential to alleviate the affordable housing crisis, and yet adoption seemed stagnant. My first reaction when seeing these printers was, “Wow, these look a lot like the PLA plastic filament printers I’ve used.” I wondered why, given that they were producing very different end products—structural housing versus plastic components.
I realized that the approach to creating construction 3D printers could be improved if a first-principles approach was taken to design printers focused on a housing product, rather than trying to adapt existing models to fit housing needs. After sketching some designs, I realized I could create a more efficient printer capable of producing cheaper, more structurally sound, sustainable structures.
What’s the problem you’re trying to solve or the gap that you’re trying to fill?
Society is facing a two-sided problem when it comes to housing: costs are too high, and the impacts of construction on the environment are too great. Roughly 1.8 billion people worldwide are facing housing insecurity, and 582,000 are facing houselessness in the U.S. alone. Meanwhile, current building processes have contributed to 11% of global greenhouse gas emissions. Looking at the New Haven community, we see that over 50% of all households in New Haven are cost-burdened, meaning they spend at least 30% of their total income on housing costs. That’s absolutely insane! We need to disrupt the housing market. At Impact3D, we’re developing a paradigm-shifting construction 3D printer that will print sustainable, affordable housing for those experiencing housing insecurity.
What was the most important resource Yale SOM contributed to your startup?
At Yale SOM, I have access to some of the top minds in social entrepreneurship and innovation. Jennifer McFadden is an advisor to Impact3D through SOM’s Founder Practicum course, and her guidance has been instrumental in getting us off the ground. Conversations and classes with professors like Teresa Chahine, Judy Chevalier, and Kate Cooney have helped me understand the nuances of social entrepreneurship and create an organizational structure that preserves the Impact3D social mission while giving us ample opportunity to scale. The Program on Entrepreneurship staff, and my peers in the space, have also been valuable resources helping me work through ideas and brainstorm strategies.
What’s the biggest milestone your startup has hit since starting Impact3D?
This summer, the Impact3D team designed, analyzed, and started manufacturing a small-scale prototype to demonstrate the feasibility of our gantry-less construction 3D printer. We went from having little more than an idea to having a scalable design with hundreds of parts that can withstand all the predicted loads and perform the complex operations for printing a wall without a gantry. We’re thrilled that we’ve hit this design milestone, and we’re even more excited about the next milestones on the horizon.
Nick Callegari is a recipient of the Selby Family Entrepreneurship Innovation Award at Yale SOM.
