A construction crew evaluation model to improve craft productivity

This research develops a tool that contractors can use to diagnose and improve craft productivity and presents the Construction Crew Evaluation Model (CCEM) to be used for that purpose. This model represents the ideal practices and procedures of a general contractor who performs work with their own forces rather than exclusively using subcontractors. The CCEM decomposes eight factors that site management can control to influence labor productivity. Also known as performance factors, they are: design, team, tools/equipment, method, material supply, area of operations, goals/feedback, and planning information. Detailed attributes and subelements are identified for each factor using an IDEF1X modeling technique. Factors are hierarchically decomposed until a level of detail is reached where attributes can be quantified and evaluated on site. Three case examples are used to verify and clearly define these factors as well as to pretest the model. A detailed procedure is developed to quantify and evaluate the as-found condition of each performance factor for a crew. This procedure utilizes structured interviews to question site personnel and direct site observation to verify this data. The CCEM was tested on crews completing cast-in-place concrete forming operations on five projects. Crews were ranked based on the closeness of fit between the as-found site conditions and the CCEM. A second ranking was done based on crew productivity, and these two sets of ranked data were compared. In every case, the crew with the best productivity was the crew where the as-found site conditions most closely matched the CCEM. It was also found that site management could improve the productivity of their crews by altering the as-found site conditions to more closely match the CCEM. A procedure which was developed to aid in this process was implemented on eight crews. Crew productivity improved from between 48% and 88% in these cases.