These residential vertical forests help clean the air

There are some fanciful architectural designs that look wonderful, almost dreamlike, in drawings, but you know will almost never get built in the real world.

One design from Italian architect Stefano Boeri, however, appears to be turning that notion on its head with his Bosco Verticale, or “Vertical Forest,” which is growing like a mighty oak in the smoggy city of Milan, Italy.

An article on the project in Jetson Green described Milan as one of the most polluted cities in Europe, with some of the worst air quality in the European Union. It’s only fitting, then, that Boeri’s design of two residential towers that will be plastered with oxygen-spewing trees and other plants was greenlighted a few years ago, if only to help clear the city’s air.

This structure of these 365-foot and 256-foot towers is nearly complete and should be ready to open later this year. The vertical forest aspect is beginning to take shape as crews are starting to hoist the first of the 900 trees, 5,000 shrubs and 11,000 smaller plants that will be planted in terraces that cover nearly every vertical façade of each tower.

The trees will take root in deep concrete planters that are situated in the nearly 97,000 square feet of terrace space around both towers. Irrigation will be partially provided by the collection and reuse of greywater on the site. Renewable energy also will be supplied through passive and photovoltaic solar methods.

Each resident of the towers will have a view of the city through the lush greenery, which will create its own microclimate that can add a number of benefits to daily life besides just aesthetic value. For instance, the plants will help mitigate smog by consuming CO2 and producing oxygen, while also providing new habitat for insects and birds. When the summer temperatures of Milan begin rising past 100 degrees Fahrenheit, the plants will provide shade and help cool the apartments to reduce energy costs. During stormy days, the well-rooted trees will act as a windbreak and will also help muffle the sounds of the streets below.


According to Boeri’s site, the verticality of the project provides both housing and urban forest space in a very compact area. The amount of greenery on the two buildings, he said, will equal an area or more than 107,000 square feet of natural forest land and about 538,000 square feet of living space—all in the space of a city block.

The Bosco Verticale project is part of a larger rehabilitation plan for the historic district between Via De Island Castillia and Confalonieri. According to Jetson Green, Boeri’s design has inspired other vertical forest ideas, including a social housing tower in Spain, called the Torre Huerta, and a “Flower Tower” in Paris, featuring nearly 400 bamboo plants.

* Randy Woods, EarthTechling