Every time passing UTS via Broadway, I could resist staring at the tallest vertical garden building designed by Jean Nouvel. It happens that there is a similar case, a pair of skyscrapers by Milan office Boeri Studio are nearing completion in the Italian city, featuring as many trees as could be planted in a hectare of forest.
The Vertical Forest has at its heart a concept of architecture which demineralises urban areas and uses the changing shape and form of leaves for its facades, and thus which hands over to vegetation itself the task of absorbing the dust in the air, and of creating an adequate micro-climate in order to filter out the sunlight. This is a kind of biological architecture which refuses to adopt a strictly technological and mechanical approach to environmental sustainability.
The building increases biodiversity. It helps to set up an urban ecosystem where different kinds of vegetation create a vertical environment which can also be colonised by birds and insects, and thus becomes both a magnet for and a symbol of the spontaneous recolonization of the city by vegetation and by animal life. The creation of a number of vertical forests in the city will be able to create a network of environmental corridors which will give life to the main parks in the city, bringing the green space of avenues and gardens and connecting various spaces of spontaneous vegetation growth.
Such kind of vertical greening, or green wall, has a similar but more comprehensive benefit than the rooftop garden that I wrote in the previous posts. 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 greywater) by absorbing the dissolved nutrients. Bacteria mineralize the organic components to make them available to the plants.
To wrap up, the green walls could also function for urban agriculture, urban gardening, or for its beauty as art.
Dezeen Magazine, 2014, “Stefano Boeri’s ‘vertical forest’”, viewed 4 June 2015, <http://www.dezeen.com/2014/05/15/stefano-boeri-bosco-verticale-vertical-forest-milan-skyscrapers/>
Ong, B. (2003). Green plot ratio: an ecological measure for architecture and urban planning. Landscape and Urban Planning, 63 (4). Retrieved June 6, 2015, from ScienceDirect database.