Assessment of production planning process in residential construction using lean construction and Six Sigma

The homebuilding industry in the United States is at its peak with the increase in demand for homes. With the projected demand for homes in sight, many companies are preparing themselves to be able to build more and more homes. Hence, it is vital for companies to adopt the best practices of production planning and control. The research aims at providing a production planning process performance assessment tool for the homebuilding industry while exploring the possibilities of using a combination of Six Sigma and Lean Construction principles to achieve the goal of zero-defect in a process. Interviews with professionals from the homebuilding industry were conducted to study the prevalent practices. Data was collected from a homebuilding site and a set of analysis tools was used to analyze the data and find areas of improvement. An assessment tool and a metric for performance assessment of production planning process were developed. A production planning process model was developed based on this study. The model is a combination of the Six Sigma DMAIC methodology and the Last Planner System. The study shows that homebuilding companies generally perceive a higher production yield than actual. Data analysis revealed that task pre-requisites, coordination with suppliers, and overestimating productivity were major causes for unreliable production planning.