Exploring the Causes of Delays in Construction Industry Using a Cause-and-Effect Diagram: Case Study for Iran

Abstract

Delays in achieving projects' objectives according to the planned schedule are considered one of the main sources of conflicts in Iran's construction industry. A precise and structured methodology and baseline to properly evaluate the root causes of delays and present guidelines has not been established, to the best of the authors’ knowledge. Therefore, there are limited perspectives on the effects of delays on the projects, creating an inefficient approach to deal with construction delays. The purpose of this study is to identify the most significant causes of construction delays, categorize and rank them to determine the root of delays, and provide a suitable solution. After extracting the main causes of delays through a comprehensive literature review and interviews, a structured questionnaire was designed to rank the delays in terms of three indices of importance, occurrence probability, and impact. In addition, when the causes of delays were identified and classified, the causes were split into eight main groups including the contractor, owner, design, procurement, equipment, consultant, labor, and miscellaneous, and the results were depicted using a cause-and-effect diagram. The findings show that the fundamental group causing delays was the contractor category, and the most critical cause was the contractor's financial problems. The primary conclusion of this study is that financial matters play a critical role in project delays in Iran's construction industry, and it is recommended that owners should take more meticulous measures to choose the most qualified contractor with strong financial backgrounds and they need to define and phase the project to their financial resources and determine an efficient financial plan for payments.