Insights Into Flow Planning in Construction: The Benefits, Challenges and Implementation

Despite the productivity gains associated with Lean Construction over the past three decades, the construction industry is still far from the improvements seen in other sectors. One aspect that has been misunderstood and poorly harnessed in construction is flow due to the differing nature of construction projects compared to manufacturing, diverging comprehension of flow, variable production rates across trades, complex logistics for tools, labor, and equipment, and the lack of a holistic model to assess flow on construction projects. This paper discusses the benefits, challenges, and procedural steps for flow planning and implementation on construction projects by interviewing 12 construction subject matter experts. The key flow planning benefits include finishing the project under schedule, improved labor efficiency, and greater work predictability. In contrast, the flow planning challenges were informational issues (incomplete design, owners making changes during construction, and not providing timely decisions), lack of experience with flow planning, material delays and defects, and contemporary issues in construction. The key prerequisites for effective flow planning include early trade partner engagement, buffer management, coaching and training, and continuous improvement. Compared to traditional schedule planning, the unique flow planning and implementation steps comprise identifying the flow scopes, planning the work zones and production math to balance production across various trades, and validating and perfecting the flow plan.