As cities are growing today, various problems are appearing and created by this growth; and Beirut is no exception. The main outcome of this is investments in land for construction, which leads to lack of open spaces and especially green spaces. Beirut is suffering from the over crowdedness of people and buildings and most importantly the lack of green spaces. On the other hand, rooftops are usually large empty spaces that resemble mostly to the empty lots before the construction of their respective buildings, so they are an urban layer that can make up for the lack of open spaces in the city, ...