Integrated Design and Manufacturing [IDM] Framework for the Modular Construction Industry Bandar Alkahlan Dissertation submitted to the faculty of Virginia Polytechnic Institute and State University in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Architecture and Design Research James R. Jones | Committee Chair Elizabeth Grant Robert Schubert Jaime Camelio Tom Hardiman May 19, 2016 Blacksburg, Virginia, United States Keywords: Modular Housing, Digital Fabrication, Mass Production, Mass Customization, Off-Site Fabrication, Assembly. IRB # 14-781 Copyright 2016, Bandar Alkahlan Integrated Design and Manufacturing [IDM] Framework for the Modular Construction Industry Bandar Alkahlan ABSTRACT If we look at the construction industry, particularly the modular single-family construction industry, we often see that the design stage is distinctly separate from the construction and fabrication stages. This separation has been occurring for some time now, however, there is often a noticeable lack of understanding of the constraints in linking architectural design to modular construction for single-family housing. In addition, no framework exists which seeks to support overcoming these constraints for the architectural design process while simultaneously bringing knowledge of fabrication, materials selection, and modular construction to the early stage of design. Also, there is a lack of knowledge of fabrication and modular construction constraints by many architects. This research intended to focus upon mapping the design and manufacturing processes for a specific scale of projects: residential single-family units. The research also aimed to understand the relationships among design, the role of emerging technologies, and manufacturing within the modular home construction industry in order to develop a design process that is based upon mass customization, rather than mass production. Thus, qualitative research methods based upon a grounded theory approach were used for evaluating, capturing, and structuring knowledge. To achieve the greatest possible amount of useful information, case studies of on-site visits to manufactured housing production facilities and structured, in-depth, open-ended interviews of architects, engineers, production managers, business managers, and other knowledge-holders within the manufactured modular housing industry were performed. The aim of this research was to map the design and modular homes manufacturing processes in an effort to better understand the relationships between these two domains. The Integration Definition (IDEF0) for Function Modeling was used as a graphical presentation technique. The goal of using such a graphical technique was, first, to understand and analyze the functions of the existing “As-is” design-manufacture communication process; and second, to enhance and improve the communication and productivity performances among people working in the design, manufacturing, and production sectors. Using this graphical modeling method assisted with mapping the design and modular manufacturing processes, including organizations, teams, decisions, actions, and activities. Through this mapping process, strategies to improve the emergent relationships were proposed as a new “To-be” design and manufacturing framework for modular single-family housing projects. Dedication This dissertation is dedicated to my parents, Sulaiman Alkahlan and Shikhah Alghanim for their prayers, encouragement, endless love and support throughout my life. Thank you both for giving me the strength to chase and reach my dreams. I am extremely grateful for everything that you have provided me with in the past and continue to provide me today to shape my life. It would not be possible to become the best person I can without your guidance, example, and awe-inspiring wisdom. I also dedicate my work to my mother-in-law Professor Haya Alrawaf and father-in-law architect Faris Alfaris for their unconditional support. Thank you both for taking the burden on and raising and educating such a great daughter throughout my entire academic adventures. I would never be able to pay back the selfless love, care, pain, and sacrifice you both did to make everything I have achieved possible. To those whom I miss the most and have been there for the start of the journey but were not able to see it through. To the memory of my beloved grandmother Norah Alrukban for her extreme strength, courage and love, and to my dear uncle Professor Mohammed Alrasheed for his constant words of encouragement throughout my graduate career. Most importantly, to the equal part in this accomplishment my wife Dr. Nasreen Alfaris who has encouraged and supported me the most during my pursuit of the Ph.D degree making the completion of the dissertation possible. I owe my academic success to my best friend, the love of my life, and companion in this journey my loving wife Nasreen whose unwavering support, patience, and trust in me are beyond anything I have ever experienced. Last, but foremost, I dedicate this dissertation to the person that has given the greatest sacrifice for this work to be completed, my daughter Ghazal. I would like to specifically thank her for giving me up throughout her childhood over 11 years of her life to provide me the chance to purse my dreams. The years that we have lost being apart have reaped their fruits and I am very excited to starting my new journey with you and finally being your dad. iii Acknowledgements First and foremost, I would like to express my deep appreciation and gratitude to my advisor, Professor James Jones, for the exceptional experience, patient guidance and mentorship he provided me, since our first meeting and throughout the completion of this degree. He has exceeded every positive expectation I had for my advisor and I believe that his unique qualities have made him the perfect fit for my interests and aspirations. On a personal level, Professor Jones’s support, understanding, and compassion over the duration of my studies have rendered him a close friend and confidant. His support has not only benefitted me but has touched my entire family and for this we will be eternally grateful. I would also like to thank my dissertation committee members, Professors Robert Schubert and Jaime Camelio, Dr. Elizabeth Grant, and Mr. Tom Hardiman for all their guidance, suggestions, and valuable comments and feedback which they generously offered over the Ph.D. years. I would also like to express my deepest and sincere gratitude to my uncle Dr. Abdullah Alrasheed for his unrelenting support and encouragement throughout my academic career. I must acknowledge my dear friend for twenty years, Dr. Anas Alfaris for being such a great source of motivation and inspiration. Thank you Anas for being available always especially during those moments when you were needed the most. To my siblings, Bashar, Abeer, Reem, and Maram thank you all for being encouraging, supportive and showing belief in me and my work. I am grateful to many friends who shared their memories and experiences during my journey. I cannot list all the names here, but you are always on my mind. Finally, I would like to thank my sponsor, King Abdulaziz City for Science and Technology (KACST), for funding and supporting this research project and for giving me the chance to pursue my Ph.D. degree in an area that I am passionate about. I look forward to my return and contributing to research at KACST. iv Table of Contents 1. Introduction 1.1 Background 1 1.1.1 Motivation 1 1.1.2 Architect Involvement 2 1.1.3 Issues of Modular Housing 2 1.1.4 Barriers between Design, Fabrication, and Construction 6 1.1.5 The Role of Technology In Support of a Paradigm Shift 7 1.1.6 New Tools for Design, Fabrication and Construction 11 1.1.7 Proscriptive and Prescriptive Theory 12 1.2 Research Approach 15 1.2.1 Goals and Objectives of the Research 15 1.2.2 Problem Statements 16 1.2.3 Research Limitations 17 1.2.4 Research Contributions 18 1.2.5 Overview of Research Methods 19 1.2.6 Thesis Structure 21 Literature Review 2.1 Introduction 22 2.2 Current Design Methods 22 2.2.1 Digital Design and Analysis Processes 26 2.2.2 Modeling Using CAD 36 2.2.3 CAD Systems in Architecture 39 2.2.4 The Design Process 42 2.2.5 Information exchange between CAD/CAM 53 2.2.6 Building Information Modeling for Collaborative Design 54 2.2.7 Sequential vs. Concurrent Design Processes 57 2.2.8 Learning from Other Industries 59 2.3 Current Prefabrication, Pre-Assembly and Off-Site Fabrication 61 2.3.1 Digital Fabrication 65 2.3.2 From Mass Production to Mass Customization 65 2.3.3 Fabrication Techniques 65 2.3.4 Design for Manufacturing 69 2.3.5 Design for Assembly 73 v Table of Contents 2.3.6 Types of Off-Site Fabrication 77 2.3.6.1 Non-Volumetric Off-Site Fabrication 77 2.3.6.2 Volumetric Off-Site Fabrication 78 2.3.6.3 Modular Building 79 2.3.7 Sources and Causes of Construction Waste 80 2.3.8 Materials Selection 83 2.3.9 Material properties 83 2.3.10 The CES Material and Process Selection Software 83 2.4 Transportation 86 2.4.1 Truck 87 2.4.2 Trailers 89 2.4.3 Modular Transport 90 2.4.4 Rail Transportation 90 2.5 Assembly 91 2.6 Summary 92 2.7 Suggested Strategies 93 Methodology 3.1 Introduction 96 3.2 Immersive Study - Grounded Theory Approach 98 3.3 Literature Review 100 3.4 The Case Study as a Research Tactic 101 3.5 Interviews as a Research Tactic 103 3.5.1 The Pilot Test 104 3.5.2 Avoiding Bias 106 3.5.3 Questionnaire Structure 107 3.6 Triangulation and Information Validity 108 3.7 Modeling Methodology – IDEF 108 3.8 Framework Development 110 3.9 Summary 112 4.