Buildings that inspire us: Il Bosco Verticale

It comes as no surprise that Blakstad architect and interior designer Alfredo Cirelli chose a building from Milan as his favourite. Cirelli launched his career within the hallowed grounds of Europe’s design industry capital, so he has a soft spot for this very underrated city. The northern Italian metropolis is not known for its beauty yet those who have the pleasure of spending time there soon get acquainted with the splendour hidden amongst her industrial façades. For Cirelli, one such treasure is the Bosco Verticale (Vertical Forest) located in the formerly industrial neighbourhood of Porto Nuovo.

Consisting of two residential towers designed by the Boeri Studio, the concept was based on an Italo Calvino novel, The Baron in the Trees, where the protagonist tires of earth-bound life and moves to the treetops to live out the rest of his days amongst the leaves. As the architectural firm behind the design says: ‘It’s a home for trees that also houses humans.’ Indeed, those lucky enough to live in the Bosco Verticale get to spend their days within the green embrace of 15,000 plants, 11,000 perennials, 800 trees and 5000 shrubs.

“This building is almost perfect,” enthuses Cirelli. “It removes CO2 from the air, it generates oxygen, it filters pollution and the light that comes through the greenery is sensational.” It seems like a fantasy conjured by a Dr Seuss fan with a penchant for expensive living (the complex’s only penthouse hit the market in 2020 with a starting price of 17 million euros). The towers rise into the sky in a cacophony of nature. Leaves shiver and billow in the breeze, vines cascade towards the ground and arborists slide up and down ropes tending to their charges. On flat land, the number of trees growing within the structure would equal a forest of 20,000 metres squared. “If we can build lungs and create fresh air in a city like Milan, we can solve so many problems,” says Cirelli. “We can eliminate the invasive and violent construction of humans.”

One of the most stunning elements of the design is the way the building reflects the seasons. In the spring and summer, it is pulsating with shades of green populated by butterflies and songbirds (1,600 of them at last count), while in the autumn, the leaves shimmer gold and copper. Finally, in winter, the trees drop their robes and let the light in. The complex is alive and constantly changing, a living mascot for a city overcome with grey. It is remarkably beautiful but also useful. Bosco Verticale processes 30 tonnes of carbon dioxide evey year. The high density of plants increases the green and permeable surfaces of the Porto Nuovo area, helping to reduce the heat island generated by glass facades, and irrigation is mostly sourced from filtered greywater from the residences themselves.

While the Bosco Verticale answers many questions related to a city’s health and wellbeing, it poses an equal number of questions. “We design for humans,” says Cirelli. “But we should design for other species too. Design is not just about humans. This is a new way of seeing architecture as something that goes hand-in-hand with nature.” No doubt this concept is the future of architecture and design but how will it play out in the real world of competing agendas? Who will get to live in these green spaces when green spaces are increasingly bulldozed by hungry cities? For now, Bosco Verticale is an exclusive experiment designed with good intentions yet mostly serving an elite few. However, it has already been replicated across the world in cities such as Sydney, Singapore, Brisbane, Paris and Nanjing among others, as well as social housing projects in Utrecht, Eindhoven and Antwerp. The template is a good one and it is up to architects and citizens to start demanding more of urban planning to solve some of the problems of our times.

In the meantime, Bosco Verticale has become a new symbol of Milan, beloved by the Milanese. It’s an outstanding achievement that has helped spawn a new movement towards greening a city that still garners a poor rating on the European Air Quality Index and periodically must ban cars from the city centre. For Cirelli, it’s an inspiration not only for its design but for the scope of the issues it addresses. “There are so many buildings that inspire me, but Bosco Verticale attempts to remove the limits between inside and outside,” he concludes. “For that it is remarkable.”