Research and Feasibility Study on 3D Printed Homes in Rural Alaska July 2021 Image Credit: Constructions 3D Image Credit: Apis Cor Image Credit: ICON Image Credit: Apis Cor Supported by: Prepared by: a Introduction Alaska Housing Finance Corporation (AHFC) is pleased to present the Research and Feasibility Study on 3D Printed Homes in Rural Alaska. Among AHFC’s values is Leadership. In that regard, we endeavor to “Be a trusted industry expert and resource.” This report is designed to advance a conversation about how exciting new technology may be applied to home construction that’s relevant to the unique challenges our state faces – while also acknowledging the limitations of that technology. As demonstrated in the 2018 Alaska Housing Assessment, rural Alaska housing is overcrowded and inefficient with residents spending a high proportion of their income on housing related costs. The rate of new construction is slow and at current production levels does not meet demand. This study evaluates the use of 3D printing, known as additive manufacturing, as a potential approach to build high-quality, rapidly deployable, and low-cost housing in rural Alaska. The study offers insightful data on the benefits and challenges to build even in Alaska’s permafrost regions. Furthermore, it examines the potential to reduce the cost of materials and the average time to build a home versus the conventional wood framework method. It also outlines the next steps to construct a 3D printed home prototype, which will further define the feasibility of 3D printed homes in rural Alaska. I would like to thank the authors from Xtreme Habitats Institute and the Pennsylvania State University Department of Architectural Engineering and Civil Engineering for their research and authorship as well as their in-kind contributions. I would also like to thank the Denali Commission for their generous financial support and the University of Alaska Anchorage Business Enterprise Institute for their in-kind contribution of time collaborating on this study. AHFC’s mission is to provide Alaskans access to safe, quality and affordable housing. We hope this study proves a useful resource for others working with us overcoming Alaska’s housing challenges and improving the quality of life for Alaskans across the state. I encourage you to read the following study and learn about the feasibility of 3D printed homes in Alaska. With any comments or questions, please contact Jimmy Ord in our Research & Rural Development department at [email protected] or 330-8446. Sincerely, Bryan Butcher CEO/Executive Director Alaska Housing Finance Corporation Team: John Anderson, Director, Research & Rural Development Jimmy Ord, Manager II, Research & Rural Development Michael Spencer, Program Manager, Research and Rural Development Prepared by: Xtreme Habitats Institute Bethesda, MD Bruce Kraselsky Chairman and Dr. Christopher Shove Executive Director With Support from: Pennsylvania State University Departments of Architectural Engineering and Civil Engineering. University of Alaska Anchorage-Business Enterprise Institute, Manufacturing Extension Partnership Funding by: Denali Commission Alaska Housing Finance Corporation Collaborators: Alaska Department of Commerce, Community and Economic Development TABLE OF CONTENTS EXECUTIVE SUMMARY .................................................................................................................... 1 Purpose ....................................................................................................................................... 1 Background ................................................................................................................................. 1 Opportunities .............................................................................................................................. 2 Challenges ................................................................................................................................... 3 Scope of Study ............................................................................................................................ 4 Methodology ................................................................................................................................ 6 Key Findings ................................................................................................................................ 7 TASK 1: ASSESSMENT OF ADDITIVE MANUFACTURING AND RELEVANCE TO LOW-COST HOUSING IN ALASKA .................................................................................................................... 10 TASK 2 RESEARCH AND ANALYSIS FOR 3D PRINTING COMPANIES ........................................ 33 TASK 3: ENGINEERING ANALYSIS OF CONCRETE 3D PRINTED STRUCTURE ........................... 79 TASK 4: MATERIALS ANALYSIS RE: SELECTION AND USE OF GEOLOGIC MATERIAL IN DIFFERENT ALASKAN REGIONS FOR 3D CONSTRUCTION ......................................................... 83 TASK 5: COST / BENEFIT COMPARISON ANALYSIS OF 3D PRINTED HOUSING VS. CONVENTIONAL CONSTRUCTION FOR RURAL ALASKA. ............................................................. 88 Conventional Construction vs 3DCP Construction Cost Per Square Foot Comparison ....... 93 Alaska Conventional Construction vs 3DCP Housing Units Production Comparison ......... 100 TASK 6: PROGRAM PLAN FOR PHASE 2 .................................................................................... 105 APPENDIX A: ................................................................................................................................ 113 Pennsylvania State University AddConLab Design and Engineering Analysis ........................ 113 Appendix B: ................................................................................................................................. 113 Analyses of concrete samples with ingredients and engineering analysis of concrete 3D printed box shaped housing structure ............................................................................................114 Figure 1: Construction 3D Concrete Printing ................................................................................ 1 Figure 2: Conventional Construction House ............................................................................... 12 Figure 3: 3DCP House Designs .................................................................................................... 12 Figure 4: 3D Concrete Printer Types ........................................................................................... 13 Figure 5: 3D Printed Concrete Samples Average Strength by Days .......................................... 15 Figure 6: Concrete Cure Time in Days by Temperature ............................................................. 17 Figure 7: Concrete Curing Time by Temperature ........................................................................ 17 II Figure 8: U.S. NSF Research Center in Antarctica On Pilings .................................................... 18 Figure 9: Alaska Last Frost Day by Region .................................................................................. 19 Figure 10: Native Alaskan House 1909 ...................................................................................... 20 Figure 12: North America Arctic Native Extended Housing Plan ............................................... 21 Figure 13: International 3DCP Buildings & Communities .......................................................... 23 Figure 14: US Government Agencies Research & Development 3DCP .................................... 24 Figure 15: 3D Printed Concrete Wall with Air Pockets Pattern & Added Insulation ................. 25 Figure 16: Diagram of 3D Concrete Printing Process ................................................................ 34 Figure 17: Example of Gantry-Style Printer ................................................................................. 36 Figure 18: Example of a Robotic Arm-Style Printer .................................................................... 37 Figure 19: Images and Summary of Apis-Cor Printer Characteristics ....................................... 39 Figure 20: Images and Summary of Batiprint3D Printer Characteristics ................................. 41 Figure 21: Images and Summary of BeMore3D Printer Characteristics .................................. 43 Figure 22: Images and Summary of Betabram Printer Characteristics .................................... 44 Figure 23: Images and Summary of Black Buffalo Printer Characteristics .............................. 45 Figure 24: Images and Summary of COBOD Printer Characteristics ........................................ 47 Figure 25: Images and Summary of Constructions-3D Printer Characteristics ....................... 49 Figure 26: Images and Summary of Contour Crafting Printer Characteristics ......................... 51 Figure 27: Images and Summary of CyBe 3D Construction Printer Characteristics ................ 52 Figure 28: Images and Summary of Hyperion Robotics Printer Characteristics ...................... 54 Figure 29: Images and Summary of ICON Printer Characteristics ............................................ 56 Figure 30: Images and Summary of MudBots Printer Characteristics ..................................... 58 Figure 31: Images and Summary of SQ4D Printer Characteristics ........................................... 60 Figure 32: Images and Summary of Total Kustom Rudenko Printer Characteristics