A green wall is a wall partially or completely covered with vegetation that includes a growing medium, such as soil. Most green walls also feature an integrated water delivery system. Green walls are also known as living walls, BIOboards, biowalls, ecowalls, or vertical gardens.

Such walls may be indoors or outside, freestanding or attached to an existing wall, and come in a great variety of sizes.

Green walls have seen a recent surge in popularity. Many Iconic green walls have been constructed by Institutions and in public places such as Airports and are now becoming common, to improve the aesthetics. For example: Edmonton International Airport(Canada),  Changi International Airport (Singapore) & Chhattrapati Shivaji International Airport (Mumbai, India).

While Patrick Blanc is sometimes credited as having developed the concept in the late 1980s, the actual inventor is Stanley Hart White, a Professor of Landscape Architecture who patented a green wall system in 1938.

Function

Green walls are found most often in urban environments where the plants reduce overall temperatures of the building. “The primary cause of heat build-up in cities is insolation, the absorption of solar radiation by roads and buildings in the city and the storage of this heat in the building material and its subsequent re-radiation. Plant surfaces however, as a result of transpiration, do not rise more than 4–5 °C above the ambient and are sometimes cooler.”

Living walls may also be a means for water reuse. The plants may purify slightly polluted water (such as grey water) by absorbing the dissolved nutrients. Bacteria mineralize the organic components to make them available to the plants. A study is underway at the Bertschi School in Seattle, Washington using a GSky Pro Wall system, however, no publicly available data on this is available at this time.

Living walls are particularly suitable for cities, as they allow good use of available vertical surface areas. They are also suitable in arid areas, as the circulating water on a vertical wall is less likely to evaporate than in horizontal gardens.

The living wall could also function for urban agriculture, urban gardening, or for its beauty as art. It is sometimes built indoors to help alleviate sick building syndrome.

( From Wikipedia, the free encyclopedia)