Semester of Graduation

Fall 2023


Master of Science in Industrial Engineering (MSIE)


The Department of Mechanical and Industrial Engineering

Document Type



A Net Zero Energy Modular (NZEM) home provides an opportunity to achieve the quality and cost savings benefits of modular construction of zero energy homes. Compared to traditional code-built homes, the NZEM home has a better insulation system, leakage-proof envelope system, energy efficient lights and appliances, high-performance windows, and solar plus storage (SPS) system. The onsite construction industry is scrutinized for its poor productivity and quality standards compared to other sectors. In NZEM construction, the factory environment removes issues that can arise during onsite construction, including weather delays and material damage, leading to higher production costs. Most factories currently use a quality control (QC) checklist called the traveler document, in which detailed inspection checkpoints and testing requirements are assigned to each module. However, NZEM home production involves additional design elements not typically addressed by current quality practices.

Additionally, the feasibility of conducting SPS installation in the factory for NZEM demands an updated QC protocol of its own, which, at present, seems lacking. This thesis aims to identify the QC challenges faced by the NZEM home manufacturers, provide recommendations for its improvement, and document the QC practices for in-factory SPS installation on NZEM homes. The objective of this thesis is achieved with the help of two papers. Paper 1 evaluates the QC protocol gap and challenges for NZEM home manufacturers and provides potential improvements in QC practices. This study was conducted via surveys and interviews with experts from modular construction companies. The survey contains four sets of questions on product and operational information of the factory and the offsite and onsite QC practices and problems. The findings provided valuable insights on prominent QC issues, identified the areas in the construction process where those issues occur, and provided potential improvements in QC practices for modular builders of NZEM homes. Paper 2 explores the QC measures NZEM home manufacturers could follow to ensure the highest level of SPS installation in their factories. This study was conducted via a case study of a manufacturer based in the northeast of the United States of America (USA). The findings from this study helped to draft a new QC traveler document that is focused on the in-factory SPS installation of NZEM homes.



Committee Chair

Isabelina Nahmens

Available for download on Monday, October 28, 2024