Recently, the international community has become increasingly interested in energy efficiency and reductions in carbon dioxide emissions. As part of the efforts, many studies have been conducted on reusable eco-friendly building structures to reflect political direction of the global community and green growth. In particular, the unit modular housing was studied in this study due to its characteristics of disassembly, reusability and recyclability. As one of an eco-friendly building structures, the unit modular housing can be prefabricated in a factory by up to 80%, and completed by assembling it at the construction site. That is, the finishing members of the connective segments of the structure can be disassembled and reused, leading to improvement of the reusability and reduction in both resources and construction waste as well. Thus, this study aims to present an efficiency plan for the integrated construction process that suits the unit modular housing construction system - manufactured in a factory first and assembled at the site later- by which the designer and the builder can collaborate with each other from the design phase.