FACTORS MODEL FOR THE STUDY OF THE PRODUCTIVITY IN MASS CONSTRUCTION OF HOUSING

Abstract

The theoretical basis for the application of The Factors Model in labor productivity studies in the construction industry is presented in this paper. The model was applied in mass production housing projects for the low-income sector. Measurement of the work made by a crew of masons building walls of concrete blocks were carried out. The foundation of the labor productivity evaluation theory is founded on the base line of each project, which is related to the design complexity. This relationship is established by means of a statistical regression model. Two attributes are defined in order to measure the quality of the work execution: The Disruption Index (DI) and the Project Management Index (PMI). The fust measures the percentage of abnormal or low productivity work days, and the second removes the influence of design in productivity measurement in order to show the effect of project organization and administration. A methodology for performance comparison between two projects is developed using the accumulated DI and PMI probability curves. The comparison is based in computing the probability of finding other projects with intermediate DI and PMI values with respect to the two evaluated projects.