A Preliminary Study of 3D Printing Home Designs for Improving Efficiency and Sustainability of Indigenous Housing in Canada

Abstract

Canada has been experiencing a significant housing crisis in recent years, especially in remote and Indigenous communities, yet most of the existing construction approaches have not been rapid, sustainable, and affordable enough to meet community needs. To address this challenge, this study explores the feasibility of 3D printed (3DP) housing and develops a design that is informed by Indigenous housing requirements and is realized through a physical design prototype tailored for the implementation of 3DP homes. Site visits and community engagement were integral parts of the research to help deliver invaluable insights that guided the design process, ensuring cultural sensitivity and inclusivity. The prototyped 3DP design offers efficient and sustainable solutions customized to the unique cultural and climatic needs of Indigenous communities in Canada. The final 3DP design seamlessly integrates traditional Indigenous architectural elements, such as a circular shape inspired by pit houses, with modern construction techniques, yielding a flexible, sustainable, and culturally pertinent home design. Future research work will be focused on how the proposed 3DP design can be adapted to enable mass customization to accommodate the diverse needs and preferences of Indigenous communities across Canada.

1. Introduction

By making construction rapid and flexible, 3D printing (3DP) technology has been gradually accepted as a prospective way to revolutionize home design and construction. For communities in Canada, such as Lytton, Merritt, Whitehorse, etc., where houses need to cater to extreme climates (e.g., uncontrollable wild fires, floods, extreme cold), 3DP construction allows printed concrete to offer the same thermal and strength properties as commonly used yet expensive insulation techniques while retaining a cost and energy saving. According to Statistics Canada, the 10-year “British Columbia Urban, Rural, and Northern Indigenous Housing Strategy” [1] aims to determine housing solutions for over 30,000 Indigenous households in the province. Despite the growing maturity of the 3DP technologies and processes, there has been a lack of a clear understanding of Indigenous housing needs and how 3DP can be adopted to improve housing efficiency and sustainability. Sustainability for Indigenous communities is a complex yet inherent property in many of their lives and practices. Through community engagement and study, the definition of sustainability for Indigenous peoples is structured around independence, growing and maintaining a workforce and population, pride, and education. All with an emphasis on the ability of the community to further define these goals for themselves and adapt their needs to come to a sustainable practice with all that goes into home building and home ownership. Each community may require specific solutions for 3DP homes to address the local climate and cultural environment [2,3]. Therefore, a preliminary investigation of Indigenous housing needs and the suitability of 3DP technology is required not only to reveal the right 3DP design factors but also to provide evidence of how 3DP is aligned with preferred housing designs to improve housing sustainability and efficiency in Indigenous communities, as defined by Indigenous communities.

The current state of housing construction in Indigenous communities can be historically summarized as inadequate. A significant reason for the current state of houses on reserves boils down to the construction methods and materials used, which have resulted in unsustainable conflicts for housing. When reviewing the report “Housing on First Nations Reserves: Challenges and Successes” [4], there are a multitude of counts of poor housing conditions. Some of these problems stem from the inhabitants while others are the fault of the infrastructure itself. With a lack of bylaws in place many reserves are powerless to force contractors to build to a standard. This is just one of the reasons for a lack of properly constructed houses on reserves. Another reason that compounds the poor construction issue is the lack of reliable funding. Many construction projects are put on pause while waiting for funding, and this leaves a half-built structure exposed to the elements, reducing its quality. A further reason why construction quality suffers on reserves, especially in rural and northern areas, is the lack of skilled laborers to build the structures. The extreme costs of transporting materials for construction also lead to lower quality materials being chosen. All these issues lead to the far too common poor construction quality found in Indigenous communities [4] contributing to inefficiencies throughout current practice and highlighting the lack of sustainable options communities have available to them.

Moreover, Indigenous architecture reflects the culture, society, and environment of the region. Building types include igloos, wigwams, longhouses, sod houses, pit houses, and plank houses. Building types are seen across various regions of Canada and are not specific to geographic regions of Canada. Locally, in British Columbia, pit houses were common across the interior Indigenous peoples. Pit houses were typically circular in shape with angled roofs, constructed of earth, timber, pine needles, grass, and bark. It is important to honor the traditional practices of Indigenous communities as architecture can be used as a form of reconciliation [5,6].

Building a structure using 3D printing techniques is an emerging approach to address the various needs and culturally inclusive designs of Indigenous housing. There are many companies and universities at the forefront of this industry, each with its own solution to how 3D printing structures should be implemented [7,8]. For example, a very popular method is based on the Gantry system which gives a nozzle movement in all three directions of Cartesian space. There are also competing methods using a robotic arm to extrude the printing material in the desired location, along with methods where multiple small robots, called aerial robots, extrude the material [9]. Once the structure has been printed the building is finished similarly to the traditional structures being built today. However, such an automation transition is not an easy task for integrating housing where specific design needs need to be defined and integrated with construction automation processes.

To address this challenge, this study developed a comprehensive research framework that includes site visits to Indigenous communities to learn about local housing needs and a prototype 3DP design that integrates traditional Indigenous architectural elements, such as the circular shape inspired by pit houses, yielding a flexible, sustainable, and culturally pertinent home design suitable for Indigenous communities. This study provides first-hand findings and insights into how 3DP technology could be potentially adopted in Canada to alleviate the housing issues across Indigenous communities.

The remainder of this study is structured as follows: Section 2 provides a detailed literature review of housing needs in Indigenous communities in Canada, cultural needs in housing, and the new process and viability of 3D printing. Section 3 describes the proposed research framework including survey, site visits, and prototyping of 3DP design. Section 4 presents the findings of the housing needs of three Indigenous communities in BC, Canada, and the performance of a completed 3DP house. Section 5 presents the proposed 3DP design prototype that integrates traditional Indigenous architectural elements, followed by discussions of the potential and limitations of this study in Section 6 and conclusions and future work in Section 7.

2. Literature Review

2.1. Housing Needs in Indigenous Communities in Canada

The complexity of needs in First Nation communities in Canada is vast. To better understand the housing needs of Indigenous communities, the report by the IFSD (Institute of Fiscal Studies and Democracy) [10] was carefully reviewed, as recommended by a member of an Indigenous group involved with this study. The report highlights the gaps in the current housing methodologies practiced in Indigenous communities, why they exist in the first place, what it would take to bridge them, and how, and accounts for nearly half the on-reserve population in Canada. Although a comprehensive understanding of each community, house, or person is subject to their respective uniqueness, a basic understanding of the gaps hindering the First Nation’s growth can help all parties involved understand the factors contributing to the unsustainability and disparity of current practices [5,6]. Gaps in the abilities to construct homes faced by First Nations include acquiring funding, labor shortages, financial literacy, and increasing population. These limiting factors and more are experienced by the communities who had participated in the study, contributing to the well-being of Indigenous communities and being critical to the proceedings of the team’s project. The housing needs are one component of a holistic grassroots approach to the well-being and prosperity of First Nations.

Projects are stunted from the inability to plan around a funding schedule, which is heavily dependent on the timely completion of applications, and even then, there is quite limited guaranteed funding. The uncertainty of funds exacerbates the inability to plan, can affect different communities in a variety of ways, and is typically worse the further away from a main city hub the First Nation is located [11]. Overall, this causes fewer houses to be built per year, heavily contributing to overcrowding in these communities. Minimal funding opportunities also pit projects into a competition of importance, leading to many needs being unaddressed in the built environment of these communities.

Education by the people and for the people of these communities contributes greatly to their sustainability goals. However, a major gap that was witnessed in the sample groups across Canada is the labor shortage [12]. Compounded by the lack of housing mentioned above, population growth is stunted, and the availability of workers shrinks [13]. Additionally, new skilled workers wanting to move back or looking to relocate to reserve land do not see the option as appealing [14]. Or worse, it is the only choice available, and overcrowding cycles continue. Without workers, opportunities for construction become increasingly distant. This is a key component in the cyclical unsustainability of current on-reserve housing, for if there is no one to build homes and no homes or facilities for skilled labor to occupy, there is no capacity to grow.

To help grow the workforce, strategies have been implemented to facilitate learning, pride, and responsibility in working for the community. The implementation of 3DP can streamline construction and cut down on the trades needed to build homes. Overhead planning and design are minimized and adaptable. A relationship with 3DP equipment companies and communities can be fostered to maximize construction windows and minimize material costs. Education on how to input community-relevant data and design using 3DP technology can be similarly workshopped, potentially with experts in each community wanting to use the method.

Overall, the consequences of the gaps in housing are rampant in many First Nations communities and slow progress for the community in one way or another include unsafe infrastructure, family tensions and violence, addiction, poor school performance, rigidity in the face of change, overcrowding, and an inability to plan. All these components compound each other, woven into a cycle unbreakable by many of these communities due to the unsustainable and volatile nature of housing projects and home ownership. Much progress has been made in recent years for First Nations communities in terms of creating a more sustainable method to house people on reserves, showcasing their resilience and adaptability. Progress has evolved to be measurable for each respective nation for their own needs and is First Nation-well-being-centered. Sustainability for many is emphasized as independence and, with the ability to reproduce similar projects in-house, communities are implementing strategies in alignment with self-sustainability such as self-ownership of their housing, fostering homeowner pride and respect with a ground-up approach. Improvements have been made but the data indicates the unsustainability of some of the efforts due to the overwhelming gaps inflicted on them. With the growing and evolving housing requirements, the team looks to leverage the capabilities of 3DP to provide a potential tool and alternative to help disrupt the depraving cycle of housing often experienced on reserves and build relationships to help close the gaps preventing a healthy sustainable life through continuing the progress in replacing the negative feed cycles with sustainable cycles structured around community wellbeing.

2.2. Cultural Needs in Housing in Indigenous Communities

Housing has long been recognized as an essential determinant of health and our sense of home is beyond physical shelter, it is associated with the personal and collective connections we have with the place [15]. However, modern architecture has taken away that connection between people and their homes. Traditional Indigenous architecture, which is based on thousands of years of knowledge and wisdom about the land and the relationship between humans and the environment, may be the best representation of Indigenous interconnected and holistic worldviews in Canada [16]. To implement cultural practices into Indigenous housing, it is important to consider the significance of these structures beyond mere shelter. For instance, incorporating spaces for family gatherings, religious ceremonies, and traditional cooking methods would enable Indigenous communities to maintain and celebrate their cultural practices within the context of contemporary housing [17]. This might involve flexible designs that allow for communal gatherings, outdoor spaces for ceremonies, and kitchens designed to accommodate traditional cooking techniques. The goal is to create housing that not only meets basic needs but also fosters a sense of cultural identity and connection to ancestral practices.

Various frameworks are delved into that highlight the multifaceted nature of housing, emphasizing its significance beyond a mere physical shelter. The World Health Organization’s (WHO) [18] framework introduces the concept of “healthy housing,” defining it as a shelter that supports complete physical, mental, and social well-being. This holistic perspective includes aspects such as belonging, security, privacy, and community interactions. The UN Human Settlements Program (UN-Habitat) [19] presents a comprehensive housing framework that encompasses environmental, social, cultural, and economic dimensions. This framework acknowledges housing as both a physical and social structure, emphasizing its integration into the broader community infrastructure. A shift from viewing housing as a cost to recognizing it as a foundation for broader social, cultural, and economic prosperity has been made. This literature review underscores the critical importance of housing as a social policy issue for Indigenous peoples, particularly First Nations, and provides a comprehensive analysis of the challenges, costs, and recommended actions to address housing gaps and promote holistic well-being.

2.3. Process and Viability of 3D Printing

Studies have demonstrated the potential of 3D printing processes such as reducing labor and formwork costs [20]. Mainstream 3D printers have been around since the mid-2000’s. Historically, 3D printing for homes is a relatively new concept with it first being used in Canada in 2021. As the construction industry becomes digitized, it has adopted new software such as building information models (BIMs) [21], as well as new building processes like additive manufacturing (AM). According to the ISO/ASTM 52900-15 Standard Terminology [22], additive manufacturing can be understood as “process of joining materials to make parts from 3D model data, usually layer upon layer, as opposed to subtractive manufacturing and formative manufacturing methodologies”. A significant drawback of traditional construction techniques is using more materials than needed. This becomes a big issue when these materials create a large carbon footprint [7]. The 3D models that make 3D printing a possibility are also an important part of innovation that allows for a reduction in waste [23,24]. This reduction in waste helps improve the sustainability of this method by mainstreaming the type of material and minimizing material costs.

The main problems that most studies focused on included the materials used, the lack of insulation research, the structural design of the buildings, and the initial cost of 3D-printed houses. The materials used in 3D printing must have certain qualities to yield a good print [25]. This means transporting large quantities of materials to the building site if they are not available in the community, reducing some sustainability aspects of this method. There has been a shift towards reducing the amount of cement in the print medium and increasing the number of environmentally conscience materials such as alkali-activated geopolymers in the mix [26]. Thermally regulating a building that has been 3D printed is a challenge that has a limited amount of development implemented. The walls do not follow the traditional layering found in most buildings, making it difficult to properly insulate. Research is being conducted on adding insulation material such as aerogels into the print material to reduce thermal conductivity [27].

There is also optimization being carried out to the print structure to allow for the addition of traditional insulation materials as well as a reduction in thermal bridges between exterior and interior walls. With how 3D printing changes how buildings are built, the structural design is also changed. With the lack of traditional structural columns and beams, 3D printed walls become load bearing [28], yet 3D printed pieces are brittle in nature which makes them less suitable for load building applications. Innovations are being pursued to alleviate this problem; one such innovation is adding fibers into the print material to increase its tensile strength. This emerging technology comes with a large initial cost. The current break-even point of 3D printing is much higher than that of conventional construction. With time and continued innovation, it is predicted to reduce to become closer to that of conventional construction. Being an early investor in this technology comes with many drawbacks that have yet to be solved, but it also offers solutions to many issues the construction industry faces.

• Research Gap

While 3D printing technology holds promise for revolutionizing housing construction in Indigenous communities, it must be adopted with careful consideration of local housing needs and cultural design factors to ensure its effectiveness as a sustainable construction practice. However, this area has been inadequately studied in the current body of knowledge regarding Indigenous housing or 3DP technology implementation. To address this gap, this study provides a solid research framework to investigate the Indigenous housing characteristics and how 3DP design can be developed to fulfill such needs explained in Section 3.

3. Research Framework

The research framework (Figure 1) mainly consists of the survey, site visits, and 3DP design prototyping to achieve the goal of a preliminary investigation of housing needs and how 3DP can be adapted to meet the needs of Indigenous communities. First, background knowledge was gained for this study from an extensive literature review and from the OCAP (Ownership, Control, Access, and Possession) training course. This course was developed by the FNIGC (First Nations Information Governance Centre) and was completed by the research team to learn the proper etiquette for engaging with Indigenous communities, as well as the importance of respecting First Nations’ data sovereignty and how to do so. In this study, all the data collected were given to each community’s representative so they not only have access to it but also own it and can do anything they want with it. We used the principles of the OCAP course to minimize the harm of third-party involvement and maximize the benefits to First Nations.

In-person engagement through site visits was used to acquire credible information from our end users, to determine their needs in order to help better reflect them in our design, and that is how we fulfilled the research gap of making construction practices more sustainable, independent, and efficient in Indigenous communities; Section 4.3 provides more details about how this can be achieved.

Data were collected using a survey that was developed by the research team based on the literature review and brainstorming workshops, and further refined by a lengthy review period. The survey was also modified throughout the process based on the respondents’ opinions, with the objective of making the questions clearer, minimizing the time of response, and maximizing the quality of responses. UBC RISe (Research and Information Systems) was involved with the review and logistics of the survey distribution, including a Letter of Consent signed by all participating parties. The survey questions are provided in the Supplementary File, titled ‘Survey Questionnaire’, and it consists of four sections with multiple-choice questions: Housing preferences (questions about the respondents’ opinion on their current homes and cultural aspects related to their housing), Housing conditions (questions about past and current residences respondents have lived in), Socio-demographics (questions about the respondents themselves), and Technical aspects (questions designed to be answered only by housing/construction managers who have more technical knowledge to share about their community housing). The FNIGC report [29] served as a basis for the research team to explore the current housing needs in Indigenous communities in Canada, and was used to validate our main survey results, which are shown in

Table 1. Comparison between FNIGC report results and survey data results.

	FNIGC Report	Key Data Results from This Study
Population information	A total of 45,662 off-reserve First Nations members were reported as seeking housing on-reserve (4.05% of total population) First Nations population (Government of Canada, 2024): 1,127,010	60 people on waiting list for housing at Indigenous community A (10.7% of total population) Total population: 560
Number of bedrooms	-	37% have 3 bedrooms, 26% have 2 bedrooms
Need of repairs in single units	Need of major repairs: 31.2% Need of minor repairs: 34.4%	Need of major repairs: 33.3% Need of minor repairs: 33.3%
Opinion about the survey	-	Enjoyed taking the survey: 77.8% Survey was creative: 77.8% Survey made them think outside the box: 66.7% Survey was too long: 11.1% Survey was too repetitive: 0% Survey was confusing: 0% Hear about study results later: 61.1%

below. This was achieved by comparing the results from the questions in their report which were similar to the questions in our report. The survey was designed using Qualtrics Software (version 2023). Regarding survey distribution, two methods were used: in-person, using tablets provided by the research team (first conducted at Indigenous community A during a community dinner that was organized by the research team, then conducted at Indigenous community C after meeting with the housing manager at their show home, to both maximize the quality of the engagement experience, our learning about the respondents, and the number of responses, and to minimize any challenges), and online using a link for the survey website or QR code provided by the research team (Indigenous communities also distributed our survey poster on their social media channels and physical copies around their communities to maximize the number of responses).

Four site visits (to Indigenous community A, Indigenous community B, Indigenous community C, and the completed 3DP housing project “Fibonacci”) were conducted as a primary case study method [30] to derive learning on the 3DP design characteristics required to meet Indigenous housing needs. Some of the survey results are presented in Table 1. The preliminary 3DP design was developed from the review of the collected data in addition to the previously documented research. The impact of each site visit on the preliminary design is described in detail in Section 4.

Autodesk Revit was used to create the parametric 3D model and Autodesk AutoCAD was used for the floor layouts and profile drawings, as well as the individual pieces for the third prototype. SolidWorks and two different 3D printers were used to print plastic tangible models.

4. Findings

The Indigenous communities A, B, and C (Section 4.1, Section 4.2 and Section 4.3) were chosen based on their location, housing managers responsiveness via email, the cost for team members traveling to the location, availability to schedule an in-person meeting, and interest in contributing to our research. The main constraints were the budget available for each trip, and logistics for collecting data within the short period of time we had to conduct this study. The same process was used to choose which 3D printing company (Section 4.4) would be visited.

The final subsection (Section 4.5) is a comparative study between all four case studies.

4.1. Case Study on Indigenous Community A

A survey of housing conditions was conducted with community A. The questions were selected such that they could be used to inform a preliminary design of a dwelling. The respondents consisted of adult community members and local housing staff. A total of 29 respondents provided effective responses to the survey questions, including housing managers and residents of community A. Over 77% of the participants enjoyed taking the survey and found it creative, and only 11% considered it too long. The site visit was accompanied by a dinner with the community catered by a member of Indigenous community A. Meaningful engagement and the formation of long-lasting relationships are key goals of the project; the trip to Indigenous community A helped foster a trusting and personal connection with the group and the community.

The advantage of 3DP is its adaptability and efficiency, which is demonstrated in the ability to implement the needs of the community identified from the survey into the design and have the voice of the community steer the design and the 3DP strategy. The needs of Indigenous community A paralleled the gaps underscored in our literature review, based overall on First Nations in Canada, which include the lack of information about Indigenous housing in Canada gathered directly from the communities. The similarities found in Indigenous community A in comparison to large data pools, such as the ones from the IFSD and FNIGC reports [10,29], rationalize and validate some key findings; for example, the number of First Nation members in Canada who are seeking housing on-reserve represents 4.05% of the total First Nations population, according to the report from FNIGC, while our data reported that 10.71% of the total population at the Indigenous community A represents the number of members on a waiting list for housing on their reserve. Another key finding was that about a third of the First Nations houses are in need of major repairs, and another third are in need of minor repairs, according to the FNIGC report, and the same proportions apply to Indigenous community A in particular, according to our data. The third finding to be discussed here was compared to the IFSD study, and it reports the significant need for new homes at the Indigenous community A reserve since 85.7% of the total number of on-reserve houses represent the current amount needed in the community. See

Table 2. Community A details.

Location	Climate Challenges	Community Population	Average Household Size	Main Dwelling Type	Main Building Materials
Lower Mainland Southwest	Wildfires, flooding, low temperatures	590 people	4 people	Single-detached house	Wood and concrete

for more information about community A.

Proper engagement with Indigenous community A was a critical step in our project. Meeting the community was one of the first steps taken in the project and provided a foundation of understanding and respect when contributing to the First Nations’ success and well-being. Firsthand understanding proved useful in the design process when applying the survey results to the design process and understanding the housing needs holistically, and that is exemplified by the size and number of rooms of our final design which consists of 3–4 bedroom and 2 bathroom houses to accommodate the current preference and needs of Indigenous community A for family homes over individual units (1 bedroom, 1 bathroom) identified in the survey results. Discussions with people from the community helped affirm our understanding that the housing crisis does not simply stem from an absence of physical houses but is a system created by current unsustainable cycles and a lack of Indigenous acceptance such as inconsistent funding, insufficient support, and a lack of acceptance and integration of First Nation innovation and methods of housing people on their land.

The housing manager of Community A stressed to the research team that understaffing is not only an issue on the management side but also the construction side, with the labor force shrinking or nonexistent in many fields of work. The community only has only one reliable electrician and one plumber who are typically busy and require advanced scheduling of their skills. These shortages are particularly difficult and amplify the difficulties in communities like Indigenous community A as they are unable to break the many interconnected challenges hindering their ability to build more housing. Cycles such as insufficient short-term housing for the workers who build them while they work or unreliable funding from government-imposed interventions and programs which cause an inability to schedule construction with certainties, demanding more and more capital to overcome, and widen the gap to achieving their housing goals.

4.2. Case Study on Indigenous Community B

Indigenous community B is located east of Calgary and has a population of nearly 7800. In the community, the largest 3D-printed construction project in North America has been taking place. A leading 3DP construction company in Canada was contracted on the project (Figure 2). The project is designed to provide a haven for individuals of Indigenous community B. The project consists of four houses currently being built. Their design is a fourplex and is currently in the process of being finished.

The site visit provided an opportunity to understand how different design elements incorporate the nation’s heritage and tradition. The main takeaways from our trip were how much faster 3DP construction is compared to traditional building techniques, how labor is minimized through this method, and how easily implementable the technology is. In terms of time savings, it only takes 4 working days of printing to finish the walls. In total it takes 2.5 to 3 months for the homes to be fully complete and move-in ready. A detailed timeline of the construction was discussed for the third building that they completed; it took 6 days for printing, a day and a half for tent take down, half a day to take the 3D printing machine down, one day to erect the roof (the roof is made of a timber truss and is built on the ground then craned on top after construction of the walls), and 2–3 days for windows and doors to be installed. In total, it takes 2 and a half weeks to arrive at a fully enclosed shell that is insulated. Drywall and steel studs take another week of labor followed by 3 weeks for interior finishing and MEP. It was emphasized that moving the printer was not a complicated process and it would only take 4 h for the team to move it to the next site. The labor reductions are evident from the fact that on a printing day, the team consists only of the project manager, print operator, pump operator, and 1–2 laborers for printing the concrete.

The design of the homes consisted of 3D printed exterior floor heating and high insulation in the walls with an R-value of R32, and the roof has R50 insulation. The houses are over-insulated to make customers comfortable with the product first then the standard will be brought down to normal. In terms of the concrete that is being used, it is batched on site with a ready-mix truck to bring the cost down. The concrete mixture being used is not different from traditional concrete, the slump is at 80–90 mm which is a bit different compared to normal concrete, and 7–8 mm aggregate is used, but otherwise, it is the same as normal concrete. A plasticizer and accelerator at the tip head are used to make application at the nozzle smooth.

The houses are made to be fire and extreme-weather resistant, the area in which the project is situated sees a high number of tornadoes and heavy winds, and the 3D-printed homes are the perfect solution to that. Indigenous community B is looking to build 50 more homes with the 3DP company, a project funded by the federal and provincial government, and First Nation community brings in a third of the project funds (Figure 3).

See

Table 3. Community B details.

Location	Climate Challenges	Community Population	Average Household Size	Main Dwelling Type	Main Building Materials
East of Calgary (Alberta)	Wildfires, flooding, low temperatures	Over 7800 people	3 people	Single-detached house	Wood and steel

for more details about community B.

4.3. Case Study on Indigenous Community C

An important component of site visits is to understand the inclusion of specific Indigenous cultural aspects the community might value in their house designs; for example, the shape of the house, the color, materials used for construction, and ceremonial rooms that should be added. However, the data we collected reported that Indigenous community A nowadays does not prioritize their traditional background when it comes to designing their homes. In that case, the housing manager from Indigenous community A introduced the D-homes project to the research team, at Indigenous community C, located west of Kamloops, BC.

See

Table 4. Community C details.

Location	Climate Challenges	Community Population	Average Household Size	Main Dwelling Type	Main Building Materials
West of Kamloops (British Columbia)	Wildfires, very dry weather	242 people	2 people	Single-detached house	Wood and steel

for more details about community C.

D-homes (Figure 4) is an Indigenous-owned business that offers 12-sided building system kits containing timber columns and beams, structurally insulated panels (SIPs), metal roofing, and roof skylights. The kits are manufactured at Indigenous community C and delivered to customers for assembly. The 12-sided design with a center skylight intends to mimic the old pit houses.

The current design is affordable, energy efficient, quick, and ready to assemble for climate-conscious homeowners. They intend to create opportunities for other Indigenous communities to be self-sufficient (using a sustainable construction method) when building their own houses once they are trained to do so. Training and lack of a workforce are some of the first challenges faced when assessing the implementation of their project; therefore, they depend on their own building crew to assemble for their customers. However, if the communities interested in the project invest in training their own community members to do the job, they will be able to build a lot more houses in a shorter period of time, which is the main goal of most communities in need of houses. The other current challenge relates to the shape of the dwelling because, with traditional construction techniques using timber, it is nearly impossible to build homes in a perfectly circular shape, which is their desired shape. The third challenge is related to resiliency against wildfires that are common not only in British Columbia but in many areas in Canada; a timber structure is not currently the most reliable option for housing in those areas.

The use of concrete in place of a wood panelized structure would increase the resiliency of the building, and timber can still be implemented in the interior since the material itself is valuable for the community. The use of a 3D printer would decrease the need for labor for the construction itself, additionally opportunities to further sustainability such as training are sometimes provided by companies such as the one studied in the case study on the 3DP housing project—the Fibonacci house described below—which sells the 3D printers. Strategies such as training and combining the effort of communities help alleviate the lack of construction labor in these communities, and the time for construction would be a lot lower than the time needed for traditional construction, and finally, they could easily design the exact shape they want.

4.4. Case Study on 3DP Housing Project—Fibonacci House

The fourth site visit was conducted to a 3DP facility in Procter, British Columbia. The project is the Fibonacci house (see Figure 5), completed by another leading 3DP company. The home is fully functional and serves as a unique example of the capabilities of 3D printing technology for the group to showcase.

The general method of construction used was not in-place printing with gantry cranes but prefabricated in a job shop and placed at the site and grouted together with the same concrete material used when printing. For example, the Fibonacci house had pieces printed at the in-house facilities and the strategy to maximize the use of the printer and work most efficiently was to print multiple sections in one print (see Figure 6). This involved designing “cut-away” or waste sections to field fit the pieces once installed.

The machine used to print the Fibonacci house was the LEONARDO-2 (see Figure 7), a stationary printer used for prefabricated projects. However, a unique and potentially more advantageous machine for the team’s project is the TILIKUM-3, a printer that can be hauled by a light-duty vehicle (see Figure 8). The TILIKUM-3 is a medium-sized portable printer, and the transportability of the printer opens more opportunities for the team with respect to rural locations. A portable option increases the feasibility and adaptability that 3D printing brings to the construction landscape. With a more portable machine, communities on reserves in rural areas become reachable and the costs of transporting equipment are minimized.

The 3DP company also offers a training program accompanying their products. Training helps contribute to the sustainability of First Nations housing by building up their skilled workforce and minimizing third-party construction involvement in their projects. Part of the process when purchasing a printer is a training session hosted by the TAM team. A tailored training program is delivered to the client ranging from instruction on how to use the software for the printer to how to set up the machine. All packages include a material handling system for mixing concrete, the printer, and a training session to prepare the users. The training ensures consistency in the product and contributes to the creation of a skilled workforce in Indigenous communities.

The pinnacle of the team’s experience was being able to stay for two nights in the Fibonacci house to experience living in a 3D-printed home. The opportunity was used to determine the livability and functionality of the house. During the stay, the research team did not feel as though any amenity or functionality was lost when compared to traditionally built homes or our day-to-day living needs. The case study helped prove the possibilities of 3D-printed concrete homes and helped define the extent of the scope of work to be undertaken by the team as well as demonstrating the capabilities of 3D printing and the many possible fields of engineering 3D printing can affect.

4.5. Overall Results

This subsection is a comparative study between the previous case studies. Each case study had its own purpose for this research. They were conducted with the purpose of complementing each other according to each of our research needs. All case studies were conducted in-person.

The first need was to establish strong relationships with communities from British Columbia and Alberta to learn directly from them about their current housing needs and challenges, as well as to introduce the possibility of a design involving 3D printing technology. From the case study in community A, we collected the data needed, shared information about this research, and established a long-term trustful connection to share more information about this study in the future.

The second need was to visualize a similar project being built and to learn about the steps needed to make such construction come to life. From the case study in community B, we not only collected some data from the community members, but we also learned about the construction steps and challenges, community challenges and budget, and 3D printing techniques in a remote area from the people responsible for the project (housing and project managers).

The third need was to find ways to include cultural aspects in our design. The case study in community C was the inspiration for the outer shape of our design, also discussed in Section 5 below. The in-person contact with the community members initiated another strong relationship to further discuss construction projects, based on the results of this research.

The fourth need was to dive deeper into 3D printing with concrete. For that, the last case study was crucial to our feasibility study so we could add the final details about the type of printers that could be used in remote communities, the logistics of such projects, and more details about the cost and labor of such projects. The last case study also fulfilled the fifth and last need of our research prior to finalizing our design, which was to experience what it feels like to be in a 3D printed construction, including the temperature in the house and aesthetics; these conclusions we draw from personal experience on top of the findings from literature reviews.

5. Proposed 3D Printing Home Design

Based on the findings, the final design was fully developed in Autodesk Revit in Figure 9. Autodesk Revit was chosen because it is a useful BIM authoring tool to provide parametric design capabilities and the potential to integrate with building performance analysis [31]. The design consists of 3D-printed walls using reinforced concrete in a circular shape, a steel and timber circular roof slightly sloped, with a conical-shaped skylight in the center; doors and windows are made of wood. The house has an entrance to the living room right in the center, the living room is directly connected to the kitchen, creating an open-concept environment, and the bedrooms and bathrooms are located around the circle in the center. There are two larger bedrooms, one of them being a master bedroom with a bathroom in it; there are two bathrooms, one for the master bedroom and the other one connected to the living room; there is a smaller bedroom which can also be an office, according to the owner’s choice, and there is a laundry room next to the kitchen. The second entrance is through the kitchen door.

The choice of designing a family home and the number of rooms was based on our survey results that is showed that most houses currently needed in the Indigenous communities are two or three-bedroom houses, which is why the third bedroom in our design can also be an office. The circular shape came from Indigenous community C’s interest in a design that is similar to the pit houses, so they can integrate part of their culture into their homes; similarly, the skylight on the roof intends to bring the cultural aspect but with the purpose of adding more natural light to the living room, so that way we keep the building well insulated. The circular shape of the living room represents the unity, connection, and equality within the family, as it represents some of the values of Indigenous communities.

The design provides flexible options for 3D printing (different printers and printing techniques), and that was based on the visits to the two 3DP companies. The symmetry of our design allows you to easily change the number of rooms in the house and the size of each space by just moving the walls around the circular living room. Finally, the size of the house can be easily scaled to accommodate people’s needs.

5.1. Prototype

The first prototype (Figure 10) was built in Revit and 3D printed in plastic using a thin layer. Once we saw the first print, we noticed that we would need thicker walls to represent the concrete walls, a different color for better visualization, and a higher slope for the roof as well. We also noticed some errors in the space between windows/doors and walls. This prototype has a 10 cm diameter.

After making adjustments based on our first prototype, we built our second prototype (Figure 11) using SolidWorks (version 2023); the second prototype was printed in plastic by a better-quality 3D printer. It has thicker walls, and it has a 20 cm diameter. Since this prototype satisfied our needs for the official design, we handmade a roof that fits it, and we added a wood floor to it as well.

Once the second prototype was ready, further iterations of the design were completed to show the flexibility of our design, and how the walls could be printed separately instead and connected later. Since we printed the walls separately, we were able to create a larger prototype that had a 40 cm diameter. The outside walls were printed ¼ at a time and are 2 cm thick. For the inner circle, we chose the same thickness as the outside walls to make it easier to attach the straight walls to it; we designed two different sizes of walls for this circle so people could choose how big they want each room. For the straight walls, we designed three different lengths so they can reach the connection hole they are supposed to reach. The connection holes were designed to fit the connection pieces from the straight walls with an angle that allows a large rotation of each piece. The inner walls ended up being loose because we considered a big margin of error that could be caused during the print; however, they worked well to allow enough rotation. The purpose of the extra holes on the outside walls is to provide more options to fit the walls in different places, but they are not realistic, and they would not exist in a real design. The floor of this prototype was handmade using a felt bag, and Velcro strips were glued to the bottom of each wall piece so we could attach and detach them easily (Figure 12).

5.2. Design Considerations

A list of design considerations has been developed for implementation when designing a 3DPC house. The considerations are summarized below.

• Minotaur (HVAC);
• Heat recovery ventilator (HVAC);
• Radiant floor heating (heating);
• TILICUM-3 (3DP apparatus);
• Leonardo-1 (3DP apparatus);
• Fly ash concrete (building material);
• Hempcrete (building material);
• Batt insulation (building material);
• Bamboo reinforced concrete (building material);
• Power bank walls (energy efficiency);
• Smart window technology (energy efficiency).

Details of the use cases and advantages and disadvantages of each of the design considerations are included in Appendix A in

Table A1. Technical Design Considerations.

Equipment	Purpose	Use Case	Advantage	Disadvantage
Minotair	HVAC	Residential homes Apartments and condominiums Offices and commercial buildings	(1) Controls ventilation, temperature, and humidity (2) Multifunctional: filters, dehumidifies, heats, cools, and renews indoor air (3) Energy-efficient operation	(1) Initial cost of installation and maintenance may be high (2) Requires regular filter replacement every 3 months (3) Requires proper maintenance for optimal performance
TILICUM-3	3D printing	Printing in rural areas and harder to reach areas	(1) Transportable by vehicles as small as LDV’s (2) More affordable level equipment	Only useful for small-scale projects
Leonardo-1	3D printing	Printing in a warehouse or larger projects at site	(1) Can print larger scale projects (2) Can be situated in a more permanent setting	(1) Costs more than other concrete 3D printers (2) Must be shipped in pieces to site
Fly Ash Concrete	Building material	Residential buildings Commercial structures Infrastructure projects	(1) Reduces carbon footprint by utilizing industrial byproducts. (2) Enhances workability and reduces heat of hydration. (3) Improves long-term durability and strength.	(1) Requires careful handling due to fine particles. (2) Longer curing time compared to traditional concrete.
Hempcrete	Building material	Residential buildings and structures	(1) Renewable and biodegradable material (2) Provides excellent thermal insulation properties (3) Absorbs carbon dioxide during curing process	(1) Lower structural strength compared to traditional concrete. (2) Limited availability and higher cost compared to other green concrete options
Batt Insulation	Building material	Residential buildings Commercial buildings Industrial structures	(1) Relatively affordable compared to other insulation types (2) Easy to install, making it suitable for DIY projects and professional applications (3) Provides thermal and acoustic insulation benefits	(1) Requires careful installation to ensure proper coverage and effectiveness (2) Can lose insulation value if compressed or improperly installed
Power Bank Walls	Energy Efficiency	Residential buildings	(1) Provides power during power outages (2) Reduction in peak power draws	(1) High initial cost
Smart Window Technology	Energy Efficiency	Residential buildings Commercial structures	(1) Reduction in heating needs up to 30%	(1) High Cost
Radiant Floor Heating	Heating	Residential buildings Commercial structures Infrastructure projects	(1) Low-cost operation (2) Helps prevent slab cracking during construction in cold weather.	(1) Relatively expensive installation (2) Must be carried out in early stages of construction.
Heat Recovery Ventilator (HRV)	HVAC	Humidity control	(1) Cost effective (2) Energy saving (3) Impact on Environment is lower than traditional methods	(1) Requires routine maintenance (2) Learning curve on using in homes for residence
Bamboo Reinforced Concrete	Building material	Low-rise buildings and structures	(1) Renewable reinforcement material (2) High tensile strength and flexibility	(1) Limited availability and suitability for certain structural applications (2) Requires proper treatment to prevent degradation

.

A construction-estimating toolkit, in the Supplementary Materials Section, has been developed as a starting point for communities to begin the estimating process. The tools are a unit price sheet, a cost breakdown sheet, and a schedule manager sheet. They were developed in Excel to be a seed, in the case of communities with no process for estimating projects in place, to grow into a system that works for them. The tools can be changed by the user and tailored to their needs and doing so is encouraged. Aspects such as energy consumption, thermal gaps, and other sustainability goals relevant to the community can be measured with existing software such as the ones offered by Autodesk and integrated with the tool kit and design. If a community already has a process in place for estimating projects, this section may not be as useful as it is aimed at communities who may be starting to build their framework for their estimating process. Additionally, the toolkit does not contain all the components to estimate a project but provides a foundation to start from and a tool to better assess the starting costs and future costs associated with 3D printing for a clearer path forward and strategy for building homes.

6. Discussion

The construction industry has been facing significant challenges including a shortage of materials and, therefore, automation and supply chain innovations are needed to revamp the current processes of projects. Three-dimensional printing processes allow for the construction of buildings without molding and formwork like in traditional construction, which provides digital fabrication capacity [32] and increased flexibility in the design of a house. This is because the construction is not constrained by the shape of the structural elements, such as the straight and flat nature of dimensional lumber used in traditional home construction. Three-dimensional printing gives the option to design curved spaces and “hide” structural columns or shear (lateral stability) elements into the wall structure. The Fibonacci house shown in Section 4.4 is designed with the Fibonacci curve as the lateral support and the column of the buildings are mono-casted into the wall structure. The ease of customization of 3DP is a significant advantage over conventionally built houses; to achieve a similar level of individuality in a structure would require complex coordination with the architecture and engineering teams.

Based on the site visit and conversations with the project staff, the 3DP buildings’ walls are insulated with R32 to deal with the cold climate. This insulation rating is above the Canadian building codes guideline of R20. Achieving this level of insulation using traditional construction methods requires the frame to be a 2 × 6 construction, adding cost over 2 × 4 construction; this is not the case for 3DP houses as they lack in-wall cross members (studs). Additional advantages of 3DP houses are that the insulation is not interrupted by the studs at regular intervals as seen in traditional stick-frame houses, better insulating the structure.

The communities uphold a very rich cultural and traditional practice, but many homes in First Nations communities are not designed to sustain traditional and lifestyle cultural practices. There is a need to incorporate culturally appropriate design elements when building new homes in these communities. Design elements are unique to each individual community, but some common ones are the use of local materials like natural wood, logs, and appropriate colors, the use of yards and porches to foster interaction with neighbors, the development of community gathering places and outdoor spaces like community gardens, trees and Indigenous plants, providing ample access to natural light, providing a community kitchen that can be used for traditional food processing and feasts, providing outdoor access to potable water for fish and traditional food processing and lastly incorporating Indigenous artwork into the design of the homes.

In this study, the ability to construct homes with unique geometries is especially important to accommodate for cultural considerations of Indigenous community homes. Three-dimensional printed construction could operate under extreme weather conditions compared to traditional construction methods since using a formwork setup would be very costly and difficult in comparison to the advantages of 3DP. Using innovative technology completely changes the way our society is constructed today, facilitating immense time and cost savings in construction and opening a door for innovation and creativity in structural design [7,33]. Also, 3DP homes allow for easier input from the owners in comparison to traditional building methods. This is due to the relatively simple construction method; a single material, concrete, placed layer by layer. This provides a promising opportunity to realize complex design options without inflating costs.

7. Conclusions and Future Work

To alleviate the housing crisis, researchers and practitioners have explored the potential of 3D printing (3DP) technology to revolutionize construction practices and offer efficient and resilient houses to meet the specific cultural and climate needs, particularly of Indigenous communities. This study developed a systematic research framework and preliminary feasibility analysis of 3DP housing construction for Indigenous communities to identify its potential to address local housing and cultural needs. The proposed 3DP design prototype was produced based on the understanding of Indigenous housing needs and an associated design “tool kit” was developed for implementing 3DP homes. Through extensive research, site visits, and community engagement, this study provides valuable insights that aided our design process and ensured cultural sensitivity and inclusivity. The final 3DP design integrates traditional Indigenous architectural elements, such as the circular shape that is inspired by pit houses, with modern construction techniques to meet the housing needs on flexibility, sustainability and culturally relevancy in communities.

Building upon this basis work, future research will focus on refining and scaling the implementation of 3DP homes within Indigenous communities, ensuring widespread accessibility and long-term sustainability. This would include a component of economic feasibility analysis of 3DP technology adoption in Indigenous communities. Additionally, future research will explore innovations in digital supply chain processes, construction materials, and techniques, with the ultimate goal of continuously improving the efficiency, resilience, and cultural relevance of housing solutions.