3D Printing as an Affordable Housing Solution in Alaska

3D Printing as an Affordable Housing Solution in Alaska

Tanaya Srini, Senior Advisor for Innovation, Office of Policy Development and Research

The 3D printer sits on tracks so it can traverse rough terrain and be driven directly to the build site. Here it is pictured ready to begin a demonstration in Fairbanks, Alaska. Photo taken by Tanaya Srini.

I recently joined colleagues from the Office of Policy Development and Research (PD&R) and Public and Indian Housing (PIH) on a visit to Alaska, where we spent a week meeting with stakeholders to better understand housing needs in the state. Our stops on the whirlwind trip included Anchorage, Fairbanks, and two subarctic communities: representatives from PD&R visited Nome and the Native village of Teller, while PIH staff went to Kotzebue and the Native village of Kivalina. Thanks to a packed schedule and the generosity of our gracious hosts, we explored the myriad barriers to housing Alaskans.

Alaska faces unique housing challenges due to its remote location and harsh climate. A common refrain we heard in our meetings was that housing solutions that work in the lower 48 are not easily translated to Alaska. Permafrost thaw, high energy costs, the delays and inflated prices that often accompany imported building materials, and capacity issues facing developers and governments alike are just a few of the factors that make Alaska one of the most challenging contexts for housing development in the nation.

Such challenges illustrate why innovative approaches such as 3D concrete printing (3DCP) may prove crucial not only for overcoming logistical barriers and reducing costs but also for demonstrating a path toward sustainable and adaptable solutions that meet the diverse needs of Alaska's remote and climate-affected communities. To further this goal, PD&R invested in developing the world's first mobile expeditionary 3D concrete printer to test whether 3DCP housing is a viable strategy for addressing the housing needs of the Alaskan subarctic region. PD&R's $600,000 research partnerships grant to the city of Nome has enabled a team of researchers, engineers, and builders to collaborate on the design, engineering, materials research, planning, and development of high-quality, affordable, energy-efficient, sustainable, and resilient 3D-printed housing in the subarctic region.

The printer, designed and manufactured by Penn State University and Xtreme Habitats Institute, sits on tracks so it can traverse rough terrain and be driven directly to the build site, eliminating the need for expensive cranes. Through a partnership with the University of Alaska Fairbanks, engineering students will test the printer, evaluating the effectiveness of different concrete mixtures to determine the best composite material for 3D printing. Students and members of the local construction trade union will also be trained to operate the printer to test which materials create the tightest and most resilient building envelopes. The printer will remain in Fairbanks until the start of the next building season, when it will begin printing housing in the field in Nome. Research will continue even at this point to ensure that this lab-tested technology can perform effectively in its intended context, and PD&R's Affordable Housing Research and Technology division will monitor the project. Our key research questions are listed below and will help us to evaluate the future success of the project.

Can 3DCP dramatically decrease the cost of building housing in Alaska?

According to the Alaska Housing Finance Corporation’s 2021 feasibility study on 3D-printed homes in rural Alaska, the cost of conventionally constructed homes in Alaska is approximately $51 per square foot, which doesn’t take into account recent soaring lumber prices. Thanks to faster construction times (the same study estimates that traditional builders would take 3 months to construct what a printer could erect in 3 days), more accurate techniques, safer working conditions, and less wasted material, the study suggests that 3D printing a similar home could reduce costs to approximately $13 per square foot — a cost reduction of nearly 75 percent. Whether builders can demonstrate these significant cost reductions in the field is a key concern of the research.

Can 3DCP homes decrease Alaska's reliance on imported building materials?

Traditional construction materials cost approximately 75 percent more to procure in Nome than they would even in Fairbanks. An expansion to the Port of Nome is slated to dredge up an estimated 2.5 million cubic yards of rocks, gravel, and sand, which could make locally sourced concrete a viable material from which to construct housing in an area where lumber is not readily available and importing conventional materials is logistically challenging. Although concrete is the largest source of embodied carbon in the built environment, we will be interested in comparing it against the emissions reductions achieved by cutting the region’s reliance on imported building materials.

The printing for this initial structure, a simple shed, was completed in approximately 3 days. Photo taken by Keith Comstock and used with permission.

Can 3DCP homes stand up to the extreme weather conditions of the subarctic region?

Alaska is the most climate-impacted state in the country, and examples of climate change and extreme weather are abundant in Nome. In 2022, Typhoon Merbok battered the coastal city with wind gusts of 60 miles per hour, the city’s highest recorded storm surge in 50 years, and flooding that reached nearly 100 kilometers inland. Temperatures regularly fall below 0 degrees Fahrenheit in Nome, and residents pay extremely high heating costs as a result.

Concrete construction may benefit Alaskans as they adapt to their changing environment; studies demonstrate that concrete can withstand more intense seismic activity and stronger winds than stick-built homes can and that the material itself is more resistant to mold and rot than lumber. More research is needed to understand how the thermal performance of 3DCP homes compares with that of conventionally constructed homes, but some studies suggest that 3DCP homes may demonstrate energy performance similar to conventional construction at a reduced cost. Beyond the material science innovations, we are particularly interested in determining whether 3DCP can generate savings on utilities and maintenance costs for residents.

Can 3D-printed homes respond to local needs?

It's clear that local needs are substantial in Alaska. Even if affordable developers can get skilled builders and needed materials to a remote location such as Nome in time to take advantage of the abbreviated building season — they can reliably plan on 4 months of construction time, if the weather cooperates — the longevity of those homes and the ability of households to reside in them are still open questions. Can their homes' foundations withstand permafrost thawing beneath them? Can their residents afford to heat their homes year round?

With these concerns in mind, we are cautiously optimistic about 3DCP as one element of a multipronged approach to building affordably, sustainably, and resiliently in Alaska. Because Alaska needs to build 27,000 homes in the next decade to meet its supply needs, 3DCP's chief strength may lie in its flexibility. Once a set of design specifications has achieved our stated goals, they can be adapted and improved on indefinitely. We could layer in culturally informed design nuances, for example, or segment the specifications to print components that allow the homes to be disassembled and moved if certain locations eventually become uninhabitable. By leveraging these adaptable solutions in Alaska, we aim to develop insights that could help address the housing crisis nationwide, offering innovative and resilient options for communities nationwide.