A studio led by Italian architect Stefano Boeri came up with the concept of Bosco Verticale, or Vertical Forest, as a way to combine high-density residential development with tree planting in city centres.
Consisting of 2 towers, which have heights of 110 metres (360 ft) and 76 metres (249 ft) respectively and host 900 trees (each measuring 3, 6 or 9 meters or 10-30 ft) and over 2,000 plants from a wide range of shrubs and floral plants distributed in relation to the façade’s position towards the sun. Botanists and horticulturalists were consulted by the engineering team to ensure that the structure could bear the load imposed by the plants.
On flat land, each Vertical Forest equals, in amount of trees, an area of 7000 m2 of forest. In terms of urban densification the equivalent of an area of single family dwellings of nearly 75.000 m2. The vegetal system of the Vertical Forest aids in the construction of a microclimate, produces humidity, absorbs CO2 and dust particles and produces oxygen.
The trees help mitigate smog and produce oxygen, and are used to moderate temperatures in the building in the winter and summer. The plants also attenuate noise. The design was tested in a wind tunnel to ensure the trees would not topple from gusts of wind.
The living façade means the exterior is constantly evolving, changing colours with the seasons and offering the Milan’s residents and ever-changing view of the cityscape.
The plants used in this project were grown specifically for this purpose and were pre-cultivated. Over this period the plants slowly got used to the conditions they would be placed in on the building.
Type of Partnership: Win-Neutral for Public and Planet
For the Public, the Vertical Forest absorbs CO2 and dust particles, produces oxygen, moderates building temperatures and reduces noise. While the Vertical Forest did not harm nature and integrated a new eco-habitat into the city, this was neither harmful nor particularly beneficial for the Planet.