Abstract

Reliability of planning commitments at operational level is one of the key factors to improve project performance. The Last Planner System (LPS™) is a tool designed to improve planning reliability in construction industry, however, the improvements in planning reliability are often limited due to the fact that the decision-making processes in construction, including those related to planning commitments, are mainly based on experience and intuition. The Rational Commitment Model (RCM) presented in this paper is a tool that helps to overcome this situation by introducing decision-making aids based on analysis of field data, which allows developing more reliable planning commitments using statistical models. RCM allows forecasting planning commitments for short term-periods using field production data such as labor available, buffer size, and planned progress. Several case studies have demonstrated the RCM forecasting capabilities and its practical use to improve reliability of planning commitments and project performance. The RCM also contributes to solve the well-known workloadcapacity problem and provides useful insight into lean production performance issues.