Critical Factors Influencing the Labor Productivity of Mass Housing Construction

Construction productivity has declined in most countries because construction projects are complex systems, and their performance levels are constantly changing under the influence of multiple interacting factors. During the last decades, most countries have sought to improve the construction sector because it is of great importance in developing the economy and creating job opportunities. To improve the construction industry, it is necessary to increase the productivity of construction workers and ensure that a decline does not affect the work plan and schedule or cause any delay or financial losses by identifying and studying the factors that affect construction productivity. To identify the most important factors affecting the productivity of construction workers, the research identified 60 factors that were collected by reviewing previous studies. The factors were divided into seven groups, namely worker numbers, supervision, contractors, materials and equipment, working conditions, project, and external factors. Because every country has different conditions due to population growth, economic crises, and housing shortages, this research aims to identify and evaluate the most important factors affecting labor productivity in mass housing projects in Iran. To achieve this objective, a field survey was conducted using a questionnaire where 250 questionnaires of important factors affecting the productivity of mass projects were distributed among people who are from institutions with rich experience, with 123 returned valid and analyzable questionnaires. The questionnaire data were analyzed using commercially available software, and the factors were ranked using the relative importance index (RII). The results showed that the five most important factors affecting productivity are in the following order: 1 = incomplete design, 2 = lack of equipment and tools, 3 = delay in payment of workers' salaries, 4 = worker's experience and skills, and 5 = lack of materials.