Residential buildings are limited to four stories above street level and if possible another four stories below, according to the Greater Amman Municipality regulations. The buildings are covered with thick white limestone or sandstone. The buildings usually have balconies on each floor, with the exception of the ground floor, which has a front and back yard. Some buildings make use of Mangalore tiles on the roofs or on the roof of covered porches. Hotels, towers and commercial buildings are either covered by stone, plastic or glass.