The effect of height and orientation of buildings on thermal comfort

Abstract

The purpose of this study is to investigate the climatic and natural capabilities to optimize open spaces. Two physical indicators, the ratio of the height of buildings to their distance from each other (H/W) and the orientation of buildings towards the street, were examined as the most critical factors affecting outdoor comfort conditions. Regarding the aspect of H/W, ratios of 0.5, 1, 1.5, and 2 were selected, which represent buildings with 3 to 13 floors at a distance of 20 m from each other. Also, about the orientation factor, angles of 135° to 200° clockwise from the north were examined. This study was conducted in Tabriz with a dry climate, cold winters, and relatively hot summers. For simulating different scenarios, Envi-met and Rayman were used. Three factors of air temperature (Ta), mean radiant temperature (Tmrt), and physiological equivalent temperature index (PET) were examined as essential factors of thermal comfort. For validation, local and field data on a simulated day were compared with the data extracted from the software. The results show that considering summer and winter, the ratio of H/W = 1.5 and the angle of 135° from the north are the most suitable.