An integrated method to valuate the function of green roofs in absorbing air pollutants; Case study: Tehran

Abstract

Tehran is the capital city of Iran and its inhabitants are suffering from air pollution.<br />Green roofs can be one of the choices to deal with this problem. In this paper, ability of<br />green roofs in absorbing four air pollutants (PM10, SO2, NO2, and CO2) in Tehran was<br />valuated. First, the potential of 1 m2 of a hypothetical green roof in Tehran in absorbing<br />PM10 and SO2 during 1 year was estimated using a dry deposition model. Absorbing<br />potential of green roof for NO2 and CO2 was taken from other studies. Next, the reduction<br />of each air pollutant was valuated using replacement cost method. Then, results were<br />generalized to the total roof areas of the residential buildings in Tehran for the green roofs<br />life span. Estimations showed that value of green roofs covering an area of 94,093,625 m2<br />in reducing PM10, SO2, NO2, and CO2 during 50 years in Tehran will be 506,361,775 $.