grasses, mosses and flowers grown on shallow low-nutrient substrates. They are also naturally self-sustaining with the
guidance of nature for water, food and sunlight etc. and require minimal maintenance with no irrigation or fertilisation
required. Likewise, extensive green roofs tackle a wide range
of environmental concerns by improving the city’s air, water
and noise quality by filtering harmful pollutants whilst capturing around 60% of rain that falls on them, making them a natural rain absorber13. As such, these roofs are not intended for
recreational use and are commonly cheaper to install than its
counterpart. An example of an extensive living roof is located in Canary Wharf Estate, London.
RECREATIONAL ROOFS These roofs are designed especially for recreation and amenity purposes such as ball games and sunbathing, which
mean they contain neither substrate nor have any intention of growing vegetation. In addition, they have minimal effect on
climate change and no biodiversity value. Examples of recreational roofs are located in Hanover School Islington and Springbok Works in Hackney, London.
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