No space for green in cities
Most cities in the world share on common problem: a lack of greenspaces. Some do better in terms of parks and trees than others, but mostly cities consist of concrete plastered over enourmous amounts of area. Globally, around 580,000 km² fall under the category of being such a concrete-plastered area. As established by the National Oceanic and Atmospheric Administration (NOAA), this is the amount of total impervious surface area in the world, which includes features created by man such as roads, buildings, parking spaces, pedestrian paths, driveways and similar structures. [1]
Living roofs or green roofs
While many of these structures and their appeal can be considered a matter of taste, roofs of buildings in particular are often space that goes unused. Apart from the obvious usefulness of providing shelter, they often fulfil no other function where they could have so many. One of them is made use of by establishing living roofs, also called green roofs.