Evaluation of the Impact of the Last Planner System on the Performance of Construction Projects

The Last Planner System of Production Control has been used in many different countries since the mid Nineties. However, most research studies developed so far have emphasized the analysis of qualitative data, based on a small number of case studies. Very few quantitative analyses have been undertaken on the impact of its implementation and on the factors that affect its effectiveness. Based on the construction of a large project database, this article presents the main results of an investigation that aimed to assess the impact of LPS based production planning and control systems on the performance of construction projects in terms of cost and time. This investigation has also analyzed the impact of a set of production management practices on the effectiveness of those planning systems. The database contains the following indicators: PPC, cost deviation, time deviation, and site management best practices index. Several analyses were carried out using regression analysis techniques. As main conclusions, the study provided some evidences on the way production planning and control influences project performance, and the importance of site management best practices on the effectiveness of planning and control. Despite the fact that some of the analyses indicated a fairly low correlation index, due to some limitations on the data available, the regression models produced were very consistent.