Green roof

Green roof at the British Horse Society headquarters

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.[1] Container gardens on roofs, where plants are maintained in pots, are not generally considered to be true green roofs, although this is debated. Rooftop ponds are another form of green roofs which are used to treat greywater.[2] Vegetation, soil, drainage layer, roof barrier and irrigation system constitute the green roof.[3]

Green roofs serve several purposes for a building, such as absorbing rainwater, providing insulation, creating a habitat for wildlife,[4] and decreasing stress of the people around the roof by providing a more aesthetically pleasing landscape, and helping to lower urban air temperatures and mitigate the heat island effect.[5] Green roofs are suitable for retrofit or redevelopment projects as well as new buildings and can be installed on small garages or larger industrial, commercial and municipal buildings.[1] They effectively use the natural functions of plants to filter water and treat air in urban and suburban landscapes.[6] There are two types of green roof: intensive roofs, which are thicker, with a minimum depth of 12.8 cm (5+1⁄16 in), and can support a wider variety of plants but are heavier and require more maintenance, and extensive roofs, which are shallow, ranging in depth from 2 to 12.7 cm (13⁄16 to 5 in), lighter than intensive green roofs, and require minimal maintenance.[7]

The term green roof may also be used to indicate roofs that use some form of green technology, such as a cool roof, a roof with solar thermal collectors or photovoltaic panels. Green roofs are also referred to as eco-roofs, oikosteges, vegetated roofs, living roofs, greenroofs and VCPH[8] (Horizontal Vegetated Complex Partitions)

  1. ^ a b Rodriguez Droguett, Barbara (2011). Sustainability assessment of green infrastructure practices for stormwater management: A comparative emergy analysis (Thesis). ProQuest 900864997.
  2. ^ Özyavuz, Murat, B. Karakaya, and D. G. Ertin. "The Effects of Green Roofs on Urban Ecosystems." GreenAge Symposium 2015.
  3. ^ EPA (2017) Green Roofs. U.S. EPA. Available from: http://www.epa.gov/heatisland/strategies/greenroofs.html
  4. ^ "Benefits of Green Roofs". www.greenroof.hrt.msu.edu. Archived from the original on 4 July 2018. Retrieved 1 November 2018.
  5. ^ Vandermeulen, Valerie; Verspecht, Ann; Vermeire, Bert; Van Huylenbroeck, Guido; Gellynck, Xavier (November 2011). "The use of economic valuation to create public support for green infrastructure investments in urban areas". Landscape and Urban Planning. 103 (2): 198–206. Bibcode:2011LUrbP.103..198V. doi:10.1016/j.landurbplan.2011.07.010.
  6. ^ "System Overview : Planted Roof : GSA Sustainable Facilities Tool". sftool.gov.
  7. ^ Volder, Astrid; Dvorak, Bruce (February 2014). "Event size, substrate water content and vegetation affect storm water retention efficiency of an un-irrigated extensive green roof system in Central Texas". Sustainable Cities and Society. 10: 59–64. Bibcode:2014SusCS..10...59V. doi:10.1016/j.scs.2013.05.005.
  8. ^ "Aurélien P. JEAN". Archived from the original on 24 August 2011. Retrieved 19 May 2011.