Surveying Green roof's Components

In recent years, there has been a great attitude toward creating green roofs in the world and our country. To fulfil consumer expectations different green systems has being introduced. As a result, there are variety of ways in order to implicate green roofs that can make it hard to decide which one to choose. In this paper after surveying and introducing some of the most used ways of creating a green roof and their components, indispensable layers of a green roof were identified and a generalized scheme of them was introduced and shown. These essential layers were respectively: roofing membrane, waterproof membrane, drainage, soil filter, growing medium or soil, and plants. At the end, given that the cost of creating a green roof is one of the important obstacles in its’ propagation, some solutions were offered. Introducing variant layers and their applications will help to choose a suitable structure for a green roof. This choice must be taken according to local conditions like climate.