Measuring Activity-Level Construction Productivity

Activity-level productivity measurement often overlooks losses due to poor construction flows - that is, the flows of workers, materials, and equipment. Using data from 138 locations and 33 crews, correlation and regression analyses were conducted on several flow metrics. The results showed that excess work-in-progress time, representing handoffs among crews, and work discontinuities, representing stoppages between locations, had the most significant association with productivity. These findings led to the development of a novel framework for measuring activity-level construction productivity. In this framework, productivity is decomposed into efficiency (measured through work sampling) and effectiveness (measured as increased output). We applied our framework to a building construction project featuring four structural work crews operating across multiple levels. The results indicate that productivity losses due to crew handoffs and work discontinuities decrease as work becomes more repetitive. Additionally, inefficiencies or idling occur when moving equipment is unavailable, whereas ineffectiveness occurs with high rework. Our framework enables the identification of various sources of productivity loss. It also helps understand that the direct work rate is just one component of overall productivity.