To create a new environmental and social balance, it is hoped that many cities will be converted into green cities in the near future, with a decisive impact on pollution levels. The vertical forest is a model for sustainable residential building, a form of metropolitan reforestation that contributes to the regeneration of the environment and urban biodiversity, without implying the expansion of cities.
The first example of vertical densification of greenery can be found in the center of Milan (Boeri 2015). It is a vertical forest, designed by architect Andrea Boeri, consisting of two residential towers of 110 and 76 meters in height, with 900 trees in the two terraces and over 20,000 plants between shrubs and flowers, distributed over the façade depending on the exposure to the sun. In terms of urban densification, the vertical forest is the equivalent of an area of a single-family house of nearly 75,000 m2.
The huge green façade made of plants reduces CO2 in the air, produces oxygen and counters noise pollution and heat island effect. In short, a vertical forest helps to create an urban ecosystem where a different type of vegetation in a vertical environment can also attract birds and insects, thus becoming a symbol of natural reconstruction and livability of the city. This innovative project, winner of many awards, including the Highrise International Award in 2014, shows how creating a series of vertical forests in a city can create a network of environmental corridors and parks, combining avenues and gardens and intertwining the different areas of spontaneous vegetation (Giacomello and Valagussa 2015). A vertical forest, designed in all major cities, as well as contributing to the mitigation of microclimate, becomes a landmark that can represent today new landscapes that change their appearance with the seasons, offering a revised vision and changeable version of the metropolitan city.
Boeri, S., (2015) Un bosco verticale. Libretto di istruzioni per il prototipo di una città foresta. Guido Musante (cur.), Azzurra Muzzonigro, Corraini Edizioni. Giacomello, E., Valagussa, G., (2015), Vertical Greenery: evaluating the High-Rise Vegetation of the Bosco Verticale, Milan Chicago, CTBUH.