Green Roofs

A green 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.

There are two types of green roofs:

  1. Extensive green roofs have less growing medium and have a limited plant palette therefore they can be very lightweight, require less maintenance and are more economical.

  2. Intensive green roofs have a deeper engineered growing medium and support a wider variety of plants, shrubs and trees. They are heavier, require more maintenance, and are costlier.


  • Reduction in storm water runoff that affects quality of local water resources which supply drinking water, are used for swimming, and serve as fish and wildlife habitat
  • Reduction in energy consumption
  • Reduction in the urban heat island effect and associated cooling costs
  • Creation of more natural green spaces, habitats for birds and urban biodiversity.
  • Opportunities for local food production
  • Doubles or triples lifespan of the roof membrane