Living Roofs are human-made vegetated areas on the top of buildings that entail a number of social a environmental benefits.
Living Roof systems, also called Green Roofs or Sky Gardens, date back to the pre-mediaeval days in Europe when sod roofs in Scandinavia were commonly used to keep country homes warm and dry. In fact it could be claimed that the oldest surviving green roof is on New Grange, county Meath in Ireland.
Today’s green roof technology has been a proven solution to energy conservation and storm water runoff since the 1960’s. Typically green roofs conserve 50-70 % of building energy use for heating and cooling. They also hold back and slowly release storm water, providing approximate 85% reduction in immediate runoff.
Other benefits of a green roof are provision of habitat to support local biodiversity, creation of green open space in urban areas, and reduction in the overall carbon footprint of a business and its building. Green Roofs are divided into two principle types: extensive and intensive.
The extensive roof is covered by a series of waterproofing membranes, a specially formulated soil mix, and a mat of living plants, commonly sedum species, which can take a lot of variation in moisture and temperature and remain low growing and attractive year round. Extensive roofs normally have limited access, primarily for semi-annual maintenance.
Intensive roofs are probably more what people image when they think of Sky Gardens. These are designed to hold a greater depth of soil, fenced for safety, and planted with garden plants selected to thrive under the variable conditions of a rooftop habitat. Intensive roofs can be used for relaxation and recreation, growing food, as outdoor rooms, and other functions of a garden area.
Living Roofs are the perfect location for composters, roof water harvesting systems and greywater filtration or Living Machines. By integrating the different technologies, considerable savings can be made on energy use, carbon budgets and resources.
Photo made by TonyTheTiger.