Evaluation of factors affecting productivity in the UAE construction industry

Productivity rates of construction trades is the basis for accurately estimating time and costs required to complete a project. This research aims at developing regression models for predicting changes in productivity, when the underlying factors affecting productivity are varied. These factors were broadly categorized as general work environment, organizational work policies, group dynamics and interpersonal relationships and personal competence of the employees as applicable to the construction industry in the United Arab Emirates (UAE). The most significant factors amongst these were determined through three surveys using the Severity Index and Chi Square computations for significance. The factors were regrouped into factors that afforded practical variation at site and productivity data was collected using different combination of the most significant factors of Timings, Supervision, Group Dynamics, Control by Procedures, Climate and Material Availability. Construction activities such as Excavation, Formwork, Reinforcement, Concreting, Blockwork, Plaster and Tiling were studied and the increase or decrease in productivity obtained was compared to the actual site average productivity; then analyzed statistically using the MINITAB 15 software, and linear regression models established. Validation was undertaken at four sites and it was observed that the regression models arrived at were capable of predicting productivity changes within ±15%.