The increasing concern about the environment brings about new alternatives to conventional construction methods. This occurs particularly in big cities, where pavement and concrete leave no room for green areas, which are vital to counteract the pollution derived from CO2 emissions coming from factories, vehicles and building activity itself.

As a result of such concern for the environment health and people living in it, vertical woods or gardens are brought forth, coming into a true urban phenomenon, a new model of sustainable urban building.

What are vertical gardens?

Although the French botanist Patrick Blanc was the inventor of vertical gardens, the vertical erection of gardens on buildings was introduced for the first time by the Italian architect Stefano Boeri in the year 2014. This form of construction is nothing but huge skyscrapers fully covered by all type of vegetation, from plants and flowers to trees, vegetation helping so that air is filtered, outside noise is reduced and temperatures are kept stable within the facilities, generating oxygen and hydrogen, and taking in a variety of animal and insect species which help in turn to preserve this vegetation.

These skyscrapers can incorporate the same amount of vegetation than a hectare of forest or natural garden, which is to say: a building 100 metres high, fully covered with a thick layer of vegetation, can generate close to 60 kilograms of oxygen per day. In addition to these facts, vertical gardens contribute to the conservation of local ecosystems and the enhancement of air quality, reducing air pollution levels.

Although this new sustainable construction model is still in an emerging phase, a few skyscrapers with vertical gardens can be found in countries such as Switzerland, Italy or China and it is intended that in the future, this sustainable model becomes an essential aspect of major cities.

Buildings with vertical gardens

  • Vertical forest in Milan, Italy. Raised by Stefano Boeri, it is one of the first sustainable buildings of this type, and it spans a forest surface of nearly 7,000 square metres. This vertical forest has in round numbers 900 trees and more than 2,000 plants of different varieties, which have been carefully distributed throughout its façade keeping in mind the building orientation in relation to the sun. The building vegetation helps capture dust and CO2 particles, which is necessary since Milan is one of the European cities with the highest air pollution levels. Besides enabling the reduction of polluting agents, plants insulate thermally the building, thus diminishing the use of HVAC equipment.

 

  • Vertical forests in Nanjing, China. This is Stefano Boeri’s last project and will open next year 2018. The same as its equivalent in Milan, this building will be comprised of two big towers fully covered with vegetation which will help reduce the pollution suffered by this large city. The building will have nearly 1,110 trees and 2,500 plants spanning a surface of 6,000 square metres, which will absorb up to 25 tons of CO2 per year, and will generate close to 60 kilograms of oxygen per day. This building contributes to environmental regeneration and reduces polluting emissions as well as the use of non-renewable energy sources.

 

  • Santalaia in Bogotá, Colombia. The façade area of this colossal green building is composed of almost 85,000 plants. The Santalaia building has 42 irrigation sectors which are regulated automatically according to environmental humidity and solar incidence. The remaining irrigation water is recycled, in the same manner of rain water. This huge green façade can produce oxygen enough for nearly 3,000 people in a year, as well as remove close to 2,000 tons of injurious gases, and more than 400 kilograms of dust. The same as its equivalent buildings in other countries, this garden regulates the building temperature, reducing the use of air conditioning and heating equipment.

Vertical gardens: a great solution facing pollution

  • They function as insulating agents and a protector of the building facing exterior atmospheric conditions.
  • Thanks to its vegetal envelope, energy consumption lessens to a great degree.
  • They attenuate the “heat island effect” which occurs in the vicinity of the building.
  • They filter polluting agents and reduce CO2 emissions, thus enhancing air quality.
  • They promote the biodiversity of plants and native animals.
  • They reduce energy losses thanks to the high level of insulation.
  • They recycle and make use of renewable energies.