Lean construction implementation and its implication on sustainability: a contractor's case study

The lean construction concept has been introduced successfully into the construction industry to reduce construction wastes. While lean concepts require a rethinking of existing construction processes and practices, there is also a need for new tools to implement lean thinking. In addition, while lean can improve project time and cost performance, it may also have an impact on sustainability, which mainly focuses on reducing environmental impact of construction. This paper describes the implementation of lean construction and its implication on environmental sustainability from a contractor perspective through a case study. The study observed waste in both project-level contractor coordination and operation-level construction performance. A vertically-integrated scheduling system that features location-based look-ahead scheduling and graphic weekly work planning was developed to improve project-level contractor coordination. To implement waste elimination solutions at the operation level, construction simulation and 3-D visualization were applied to facilitate lean implementation. Meanwhile, the impact of lean on sustainability were observed and discussed.