Extensive green roofs are lightweight with a shallow layer of growing substrate of less than 200 mm deep requiring minimal maintenance.
Green roofs literal meaning.
Container gardens on roofs where plants are maintained in pots are not generally considered to be true green roofs although.
A green roof or living roof is a roof of a building that is partially or completely covered with vegetation and a growing medium planted over a waterproofing membrane it may also include additional layers such as a root barrier and drainage and irrigation systems.
Green roofs have traditionally been categorised as extensive or intensive.
Although there are no precise definitions of them an extensive green roof has a shallow growing medium usually less than six inches with a modest roof load limited plant diversity minimal.
A green roof can also provide a refuge for insects and birds that have lost their natural habitat due to urban development and the loss of green space.
Green roofs are also known as vegetative or eco roofs.
They generally have lower water requirements and use small low growing plant species particularly succulents.
Some green roofs incorporate urban agriculture and include herbs and vegetables that can be harvested for use by the building s occupants or the community.
Because green roofs require professional design careful structural analysis and multiple layers and systems even extensive green roofs usually start at 8 per square foot significantly more expensive than the 1 25 per square foot for built up roofs burs source.
The initial expense of green rooftops often turns away prospective clients.