Overall Construction Productivity: a new Lean Metric to identify construction losses and analyse their causes in Engineer-to-Order Construction Supply Chains

Construction projects are often unique, time-limited and require a high degree of customization by involving a significant number of Engineer-to-Order (ETO) components. Usually, ETO construction supply chains are composed by a fabrication part off-site and the installation part on-site where different supply chains have to be merged. Generally, many problems are identified during construction on-site and often in a late phase when recovering actions cannot be applied anymore. As a result, construction projects frequently face delays and budget overruns. Owing to these considerations, the paper proposes (i) a framework able to identify the losses and causes of ETO construction supply chains and (ii) a novel metric named Overall Construction Productivity (OCP) supporting the quantification of the overall impact of losses and the implementation of improvement actions. The proposed framework and metric were applied and validated in a medium-sized ETO façade supplier company and a hospital construction project.