INTRODUCTION Increasing urbanization and industrialization has caused the urban environment to deteriorate. The urban climate and the environmental efficiency of buildings are influenced by the deficiencies in proper development control (Santamouris, 2001). As a consequence of changes in the heat balance, air temperatures in densely built urban areas are higher than the temperatures of the surrounding country. This phenomenon, known as the urban heat island (UHI) effect, is a reflection of the totality of microclimatic changes brought about by man-made alterations of the urban surface (Landsberg, 1981). UHI was first identified by Luke Howard in 1820. He found out that in London, nights were 3.7°F warmer and days were 0.34°F cooler in the city than in the country. Heat island intensity differs in different parts of the city – the greatest intensity usually being in the

most densely built areas. In high-latitude cities with cooler weather, heat islands can be an asset in reducing heating loads, but in mid-and low-latitude cities, heat islands contribute to urban dwellers’ summer discomfort and significantly higher air-conditioning loads.