Analysis of Causes of Delay and Time Performance in Construction Projects

Activity delays are a common issue in the construction industry and can increase project schedules and costs. Recent research efforts have focused on the quantitative evaluation of delay impacts. The literature suggests that the construction industry is in need of additional research to systematically relate the causes of delays to their impacts. To overcome this limitation, this paper analyzes delay causes in activities that were not completed as scheduled. The paper contributes to a methodology to examine the qualitative (delay causes) and quantitative (time performance) dimensions of the delay issue. The paper proposes two indicators, as follows: (1) reason for noncompliance (RNC) as an indicator that characterizes scheduling failures, and (2) delay index (DI) as a time-performance indicator that describes the impacts of delay on critical and noncritical activities. The paper presents two building projects as case studies, with planning and subcontractors as the primary RNCs that have the greatest impact on time performance. Planning was the most harmful delay cause on time performance.