Abstract
The time and costs associated with HVAC system installation are significant percentages of the total time and cost of construction projects. Furthermore, these systems affect many of the other construction activities. They are complicated, and their installations face many risks, which may lead to time and cost overruns for the project. Therefore, more attention should be paid to how these systems are installed in construction projects. The main objective of this study was to identify the main activities associated with HVAC system installation in construction projects, as well as the risk factors that affect them. Other objectives included conducting an analysis and assessment of the effects of these risk factors on time and cost objectives. Multi-stage field surveys were used in this study. The major risk sources were qualified in terms of their severity, probability of occurrences, and impacts on time and cost objectives. Three activities associated with HVAC system installation were identified: (a) air distribution duct work, (b) chilled water distribution pipe work, and (c) HVAC equipment installation. Fifty-five risk factors that affect each specific activity and that are common to all activities were also identified and categorized into four groups. Two agreement analysis tests and a full statistical analysis were conducted. A high degree of agreement between all partners was obtained. The time and cost percentages of the three activities were determined. A detailed discussion and analysis indicated that approximately 50% of the key risks belonged to common risks that affected all activities, while the most important risky activity was chilled water distribution pipe work. Furthermore, the analysis emphasized that the number of risk factors increased as the expected duration of the activity increased; however, this relationship did not exist in the case of cost. Ultimately, the obtained results indicate that the expected time and cost overruns caused by the effects of risk factors on HVAC system delivery are approximately 10–20% and 5–10%, respectively.
•Identify the main activities associated with HVAC system installation during construction projects.•Identify risk factors affecting the HVAC activities.•Assess the effects of the risk factors on the time and cost of activities of HVAC systems.•Ascertain the key risks that can significantly influence the delivery of HVAC systems in costruction projects.•Identify the time and cost weights of the of the HVAC system activities.