Creating livable green spaces in the middle of urban sprawl is a great goal. And good work in elevated green spaces has been done in the last 10 years. This image is a rendering of a proposed huge green roofing and park project spanning many buildings (double the size of the current largest green roof).

Rendering of proposed green roof.

The whole development seems pretty spectacular and the huge green roofing concept is very cool. I wonder how likely it is to be developed? The location in the Silicon Valley makes it much more likely it seems to me as there is plenty of money there for extravagance. The entire project is estimated at $3 billion.

World’s largest green roof unveiled in the heart of Silicon Valley

The Hills at Vallco’s crown jewel is without a doubt its $3 million 30-acre green roof, an unprecedented engineering feat that’s “at least twice as big as anything attempted before it.” The elevated community park will include 3.8 miles of walking and jogging trails along rolling hills, orchards, vineyards, meadows, organic gardens, children’s play areas, and a sanctuary for native fauna and flora.
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On street-level, the new mixed-use neighborhood will feature a highly walkable and bikeable downtown street-grid anchored by two town squares. Parking would be primarily tucked underground and a transit center may be built at the shopping center. The 15-block street grid will be filled with 625,000 square feet of retail, 2 million square feet of office space, and 800 residential units.

I am not sure what the $3 million price tag includes. It sure doesn’t seem like much money given the scope. My guess is it must exclude most of the costs – such as creating the infrastructure for laying the green roof; unless it is much cheaper than I would think.

The development site sits between Apple’s Infinite Loop headquarters and the spaceship-like Apple Campus 2 in Cupertino, California.

Related: The Benefits of Green Roofs – University of California, Berkeley: 2010 Livable Buildings Awards – Wonderful Low Impact Woodland House with a Green Roof