Stefano Boeri's Bosco Verticale in Milan has been called "the most exciting new tower in the world." Last year it won the International Highrise Award, described by the judges as "a striking example of a symbiosis of architecture and nature." Now he is building another 36 storey tower in Lausanne, Switzerland, to be planted with cedar trees. (Hence the name "La Tour des Cedres")
According to Dezeen, there will be 100 cedar trees, 6,000 shrubs and 18,000 plants. Boeri is quoted in Dezeen:
With the Tower of Cedar Trees we will have the opportunity to realise a plain building that will have a great role in the Lausanne landscape," said Boeri in a statement. "An architecture even able to introduce a significant biodiversity of vegetal species in the middle of an important European city."
"The Tower, also thanks to its shape and the changing colours of cedar trees and plants during the seasons, could become a landmark in the panorama of Lake Geneva," the architect added. "This will make Lausanne a cutting-edge city in the global challenge to implement urban quality together with sustainability and biodiversity."
I have expressed some reservations about Boeri's placing of trees up in the sky in big planters; in comments responding my last post on the Bosco Verticale, I was accused of a " tendency to negativity". Another commenter wrote: " I can't help but realize that every post Lloyd writes has a downer ending. Can there just be one Treehugger post that doesn't have a negative tone?"
But I feel it important to say it again. Trees are lovely things, and may well thrive in these planters in the sky. However when discussing sustainability, one has to look at the whole picture. Trees, and the soil they need to survive and grow, are heavy and it takes a lot of reinforced concrete to support them on these cantilevered balconies. Concrete is responsible for 5 to 7 percent of the carbon dioxide we produce, so the responsible and sustainable thing is to use less of it. Without an analysis of how much concrete is needed to support these trees, vs how much CO2 the trees absorb, you can't call this sustainable design.
I also worried in previous posts that the planters might not be big enough to ever support the growth needed to make the building actually look like the rendering (and did not make this up, I did check with landscape architects who questioned it too).
However, on the positive happy side, these tree supporting balconies appear to be boxes rather than just slabs, the planting doesn't look quite as dense, and they may well be more efficient in their use of concrete than the Bosco Verticale was because of those end walls on the boxes. Also, studies have shown that nature and trees make us nicer people and they certainly make for nicer apartments. And, this site is called TreeHugger.
So there you have it, an upbeat ending.