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A Milan Skyscraper With A Forest Inside It

Finding land for new parks can be hard in a dense city. But not if you put them in buildings. The concrete jungle just grew some plants.

We may need to start building our parks in the sky. In the 1850s, New York City needed a place to escape from its own urban crush. It was easy enough to evict more than a thousand poor tenement dwellers and re-landscape the heart of Manhattan, creating what we know as Central Park. Today, such a  project would prove far more difficult, if not impossible, in most of the world’s major cities. Vertical greenspace may be one answer to that problem.  

The Bosco Verticale towers taking shape in the northern Italian city of Milan, although private residential towers, show the technology is more than possible. Designed explicitly to house at least as many trees as people, the buildings make room for plenty of apartments (ranging between $870,000 and $2.6 million for the penthouse) as well as 730 trees, 5,000 shrubs and 11,000 ground plants, according to the U.K.'s Daily Mail.

The vertical forest spreads out one hectare of woodland across 27 floors. And it’s only just the beginning. The $90 million buildings are the first in a series of proposed green belt project called BioMilano, which could encompass dozens of abandoned farms on the outskirts of the city.

This doesn’t make them particularly expensive. Accommodating the vegetation only added about 5% to construction costs, according to the Financial Times. Compared to the equivalent area for individual homes and woodland, at least 12 acres of land, and 2.5 acres of forest, would be needed. Boeri Studios, its creators, hope the buildings set a new standard for green design.

Other architects are working on the same challenge by taking the biological metaphor to extremes. Harmonia 57, a building in Brazil designed by Triptyque, actually  "breathes and sweats." Plants embedded in porous concrete walls are watered with a mist that shrouds the whole building. It creates the appearance of a building returning to the jungle, rather than the urban grind.

But most green buildings today merely evoke the forms found in nature. Few ever actually invite it in to play. We settle for energy efficiency and responsibly sourced materials instead. While that’s all well and good, architects are finally starting to craft biological buildings in cities that blur the line between green space and living space.  

Boeri Studio

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  • Jon Neff

    I wonder what the water consumption is.........

    However, some of the comments below are invalid.

    1.  Shrubs (not trees) can be selected for each side according to their needs for sunlight.

    Shrubs are also determinate (they will only grow just so high).
    The challenge would be to control the amount they spread. 

    Keep BONSAI in mind.  If it works on such a micro scale, why not on a medium scale.

    The shrubs won't expand beyond what their root systems and water supply allow them to.

    I think all these obstacles (with the exception of the water issue) can be overcome.

  • Natanael Valenzuela

    Eventually!!! Keeping those trees under control.. for growth and sicknesses, and birds, and other animals...Dont forget the roots!!! No.. Those buildings will be very heavy specially under rain and heavy weather. NOt to mention if the wind blows and then those trees start falling down and killing people.  Will prove this to be a failure! It reminded me how easy is to plant trees around the city and in sidewalks. 

  • Janaya Hanley

    Prototypes of these buildings were tested in a wind tunnel to attempt to prepare for exactly this problem. I'm interested to see how they handle wind.

  • Natalia

    Incredible!!! We need more initiatives like this! Who are the architects of the project

  • forester

    This is going to be tough... healthy trees have root systems as large as their crown (the part with leaves), so unless they also have huge pots for the trees, they won't be growing really large.

    As an aside, does anyone notice that all architectural and planning renders always have vibrant trees, but in real life the trees need to constantly replaced because they die? The cost of replacing trees is pretty big, which I am not sure they included in their pricing. Similarly, how are they going to get trees up to the floors that need them? If they're constantly growing saplings, the building is going to always look incomplete. 

    The trees on the south side of the building will also look different from the ones on the north/east/west sides of the building because of different amounts of sunlight, or they'll stretch their branches out to get the sun on the east and west sides of the building... 

    Also, if the trees aren't competing with each other for light, they won't be growing big and large as they're depicted. It's a good idea, but man did they drop the ball on the science.

  • Jim Pettit

    I think this could work, even with the difficulties of engineering for wind load and such. Once mature, the plantings would look stunning, act as perfect CO2 scrubbers, provide habitat for birds and insects, help to offset the urban heat island effect, and partially break-up the drab, industrial granite-and-glass towers that comprise most modern skylines. Too, I've been a big proponent of vertical farming; how cool would it be to plant a few low-maintenance fruit trees suitable to such xeriscapes?

  • Maggie Scott

    I'm rooting for something like this to work, but I'm skeptical. I'm sure Boeri Studios has done their due diligence with sun studies and maintenance estimates, and I have no doubt that on opening day, the building will look like the rendering but... a skyscraper is a significantly complex structure without adding biological bows and ruffles on the side. Nevertheless, like most folks commenting here, it looks awesome, and I hope they find a way to make it succeed.

  • Alex Hughes

    whats maintenance cost on a this building??? do the gardeners get free apartments? none the less its awesome

  • Megan Scarborough

    While I think this is a cool idea and super neat looking, I'm curious what the *point* of it is... Part of the issue with deforestation is not just the loss of trees but the loss of habitat. Can animals live in these trees? Should they? Will they? I certainly can't imagine the towers replacing the complexity of a forest ecosystem. If the point is just to have trees and absorb more CO2, let out more 02, that would seem to make sense. The other reason I can think of is that the trees might hold in heat and help keep energy costs down that way... But it doesn't seem like it would be the most efficient way to do that. I'd be curious what the original reasoning behind this was, whether it's simply beautification/adding green space, environmental or ecological. Seems like an important angle the article left out. Though I guess this is still pretty theoretical... Hm. Like I said, v. cool.

  • gbacoder

    I would be careful to put this one down while still in the idea stage. They may be able to find ways to make it work. Those pots look pretty big to me compared to a person. I just did a google image search for "container trees large" and saw that big trees grow in very small pots compared to the size of the tree! The ones in the above images are just fine. Also to those that say the building will collapse, modern buildings are very strong, and can be made stronger IF need be. 

    And those that say leaves will fall, well we have trees lining the streets in London, and we just sweep them up with special vehicles. Not a problem. 

  • Matt

    And then Fall roles around and dumps leaves everywhere. Then it snows collecting winter deposits and adding weight. Is there some sort of safety net down off of the first floor?

  • the_engineer

    This is great and all but those renders must be some sort of a joke. Certainly those tiny pots can't actually support the root system needed to hold up some of those trees under the wind load they're going to be seeing. I can see saplings and whatnot but there's going to be a lot of busted "tree pots" or whatever you want to call them if the trees aren't very carefully selected and the root systems carefully maintained. This isn't putting a forest anywhere, it's just putting a bunch of huge flowerpots on the sides of a building.

  • Perpetuasystem

    With the wind load, there are going to be some trees coming off of the building, I do believe. 
    better to put the trees in an interior garden space, and use living wall surfaces on the exterior. 

  • Ken

    Yeah I agree.  This is just fantasy land nonsense, meant to appeal to the sort of hippy-dippy people who live in San Francisco ("oh that's SOOO wonderful!  if only the Evil Developers would do it!")

    As always, fantasy breaks down on the simple application of logic.  Plants grow, you know.  And there is the fact that birds, bugs and squirrels will want to live in them; and poop everywhere.  Then there is the matter of logistics.  Water, plant food fertilizer will need to be moved in , and dead trees and pruned limbs will need to be moved out.  With all those trees, that will be quite an expense.

    That's probably not even the half of it.  Generally, not a good idea.