The additive construction (AC) sector is really beginning to bloom and, while 3DPrint.com Executive Editor Joris Peels has qualms with the idea, 3D printed houses in particular are becoming the key demonstrator for it. The latest AC home comes from the University of Maine Advanced Structures and Composites Center (ASCC). Dubbed BioHome3D, it is described as “the first 3D-printed house made entirely with bio-based materials.”
BioHome on the Range
The prototype home measures 600 square feet and features 3D-printed floors, walls and a roof made up of wood fibers and bio-resins. Not only that, but it features 100 percent wood insulation with customizable R-values. That is, the resistance to the conductive flow of heat can be customized. According to the team, the house is completely recyclable and construction waste was almost entirely eliminated due to the precision of the printing process.
“Many technologies are being developed to 3D print homes, but unlike BioHome3D, most are printed using concrete. However, only the concrete walls are printed on top of a conventionally cast concrete foundation. Traditional wood framing or wood trusses are used to complete the roof,” said Dr. Habib Dagher, ASCC executive director. “Unlike the existing technologies, the entire BioHome3D was printed, including the floors, walls and roof. The biomaterials used are 100% recyclable, so our great-grandchildren can fully recycle BioHome3D.”
The home was made off-site using locally sourced wood fiber feedstock combined with a wood fiber-PLA composite from NatureWorks, a company that is jointly owned by Cargill, the largest privately owned company in the U.S., and the Thai state-owned oil and gas business PTT Public Company Limited. The team 3D printed the house as four modules that were then assembled on site in half a day. It took just two hours for electricity to flow through the home, with only a single electrician required. Located on a foundation outside ASCC, the structure is outfitted with sensors that track the environmental, thermal, and structural information of the home as it weathers Maine’s winter season.
Bio vs “Bio”
The label of BioHome3D as “the first” 3D printed home made from bio-based materials seems somewhat tenuous, given the fact that, in 2019, WASP 3D printed a tiny house called GAIA that was made from soil and agricultural waste. This was followed by the TECLA home in Italy and DIOR store in Dubai, also made from locally sourced natural materials.
To clarify, the BioHome3D team told 3DPrint.com, “The definition we use for 100% Bio-based materials are those raw materials derived from living organisms including for example wood, crops (such as corn, hemp), or algae. The WASP project used local sand/soil obtained from near the site, which are not bio-based materials. Although locally found, these are mostly minerals; while they are abundant, they are either bio-based nor renewable.”
It is interesting to note that a biopolymer like PLA is traditionally unable to be degraded outside of an industrial composting facility. It also cannot be recycled without losing some of its mechanical properties. In contrast, raw earth can be reintegrated into the natural environment as well as reused as a building material indefinitely.
Nonetheless, the BioHome3D is a unique AC implementation and Tiziana Teghini, Marketing Advisor at WASP, suggested that improving the world through AC will take diverse approaches, telling 3DPrint.com: “Our ultimate goal is that we can build a better world for the planet. In my opinion, it’s not about what’s best or who did it first… it’s about changing the culture and fighting for the greater good.
Collaborating with ORNL
Developed with funding from the U.S. Department of Energy’s Hub and Spoke program, UMaine and Oak Ridge National Laboratory (ORNL) worked with MaineHousing and the Maine Technology Institute to make it happen. ORNL had previously used a variation of the Big Area Additive Manufacturing system from Cincinnati Incorporated to 3D print a home in 2015. This project was made using the MasterPrint polymer 3D printer developed by ORNL with UMaine and Ingersoll. It is most well known for its 3D printing of a boat hull in 2019, then the world’s largest 3D printed boat and solid object.
At the home’s unveiling were Maine Governor Janet Mills; U.S. Sen. Susan Collins; Jeff Marootian, senior advisor for energy efficiency and renewable energy for the U.S. Department of Energy; Rebecca Isacowitz, acting chief of staff for the office of energy efficiency and renewable energy at the DOE; Steve McKnight, acting advanced manufacturing office director for the DOE; and Xin Sun, associate laboratory director for energy science and technology with ORNL.
Additive Construction and the Housing Crisis
Like many 3D printed homes, BioHome3D is being touted as a demonstration of AC as a solution to a global housing crisis. The project team cites the fact that Maine lacks 20,000 housing units with almost 60 percent of low-income renters in the state spending over half their income on housing. This is further exacerbated by unemployment and material price increases driven by supply chain issues.
“Our state is facing the perfect storm of a housing crisis and labor shortage, but the University of Maine is stepping up once again to show that we can address these serious challenges with trademark Maine ingenuity,” said Gov. Janet Mills. “With its innovative BioHome3D, UMaine’s Advanced Structures and Composites Center is thinking creatively about how we can tackle our housing shortage, strengthen our forest products industry, and deliver people a safe place to live so they can contribute to our economy. While there is still more to be done, today’s development is a positive step forward — one that I was proud to support through my Maine Jobs & Recovery Plan and my budget. I extend my congratulations and thanks to the University of Maine and its partners, and I look forward to continuing to tackle these problems with innovative solutions.”
“With today’s production of the world’s first ever 3D-printed house made from recycled forest products, the University of Maine continues to demonstrate its global leadership in innovation and scientific research,” said Sen. Collins. “This remarkable accomplishment was made possible by the tenacity and expertise of Dr. Habib Dagher, his team and students at the UMaine Advanced Structures and Composites Center. I commend them on pioneering this new market opportunity for Maine’s forest products industry, which could help alleviate our nation’s housing shortage. Their groundbreaking work will lay the foundation for the future of affordable housing and help create new jobs across our state.”
However, as we learned from Peter Cohen is the Co-director at the Council of Community Housing Organizations (CCHO) in San Francisco, AC alone is not a panacea for providing shelter to the population at large. A potentially more energy- and resource-efficient solution to the housing crisis could be to commandeer existing buildings, such as unused apartments belonging to investors abroad, and convert them into public housing. Such an attempt to de-commodify real estate is likely impossible in the current social, economic, and political reality.
Technological approaches, however, are much more apt to receive positive press and funding from public and private entities. AC, along with additive manufacturing as a whole, has the primary benefit that it automates production. This makes it possible to address the labor issue by circumventing it. This may be one of the reasons it’s being so heavily pushed by the United Arab Emirates, where strikes are particularly pernicious in the construction sector.
UMaine’s Future Additive Construction Endeavors
To scale its AC research, ASCC is opening its Green Engineering and Materials (GEM) research Factory of the Future. The facility will serve as a basis for AI-enabled, large-scale hybrid manufacturing. In part meant to revitalize the state’s economy, the GEM site will also be key to creating the new Maine College of Engineering, Computing and Information Science’s (MCECIS), which integrates engineering and computing education and research.
GEM is being driven by $25 million in direct investment, including including $15 million through the Maine Jobs & Recovery Plan and $10 million in federal funding. Almost $40 million more in other federal funds are being pursued by the state’s senators.
All images courtesy of the University of Maine.