Prioritize and analyze barriers for rooftop greening in Tabriz, Iran

A green rooftop is a novel element in modern architecture, inspired by the sustainability concept developed for urban environment. It is used for increasing green space per capita, improving environmental quality, and sustainable urban development. Meanwhile, some factors hinder the development and utilization of these architectural elements in cities. In line with this research problem, the main objective was to identify and to prioritize the factors, limiting green rooftop development in Tabriz city, Iran, to recommend operational procedures and a method for sorting out the limitations and obstacles. According to the literature, reviews and experts' opinions through Delphi technique, first of all, five pivotal obstacles (factors), restricting green rooftop development, have been determined including "cost and investment" factor, "cultural and educational" factor, "scientific and technical" factor, "climatic and ecological" factor and, finally, "legislation and management" factor. Then, a sub-situated group of factors was prioritized within each of the major pivotal factors, using the analytical hierarchy process. Afterward, each factor has been investigated according to its effects and statistical significance for Tabriz city. Finally, the statistical significance (priority measures) was determined for the major factor sets. The final set of factors have been compared to the alternatives, considered around the world. This research attempted to spot out and identify major and serious bottlenecks facing green rooftop development generally in Iran and particularly in Tabriz. Some practical and concrete solutions were presented in this paper, especially offered for the developing countries.