TreeHugger has been following the work of Broad Sustainable Buildings since 2010 when they built their first hotel in in a week. Broad has developed a flat-pack prefabrication system that lets them build on site extremely quickly; the buildings are energy efficient with 8 inches of insulation and quadruple glazing, along with terrific air quality, with 3 stage air purification, particulates reduced by 99.9%, 7 air changes per hour and 100% fresh air that's run through heat recovery ventilators. It's got combined heating, cooling and power, (Broad's main business is air conditioning) making the building 80% more efficient than conventional buildings. Broad claims that this one building saved 15,000 trucks full of concrete.
When they topped off their biggest, the J57 tower at Broad City in Changsha, I noted that their buildings are efficient, healthy, and high quality. But I also wondered about the atriums, the three storey high spaces in the middle of the buildings, seventeen of them stacked on top of each other- what are they going to do with them all?
Evidently they were not sure either, and instead of deciding themselves, Broad is running an international competition to search for creative uses.
SkyCity is currently unoccupied and contains 17 hollow internal courtyards interconnected by a long spiral bike ramp that ends on the top of the 57th floor of the skyscraper. The goal is to create 17 public spaces that will interact with the future inhabitants of the tower. Afterwards we plan to convert the rest of the tower into an alternative co-housing / co-living complex we call SkyCity. The objective is to provide maximum freedom to the participants to engage the project without constraints in the most creative way. What is a courtyard in the middle of a vertical skyscraper in the 21st century?
The courtyards are 20m (66’) by 16m (52’-6”) by 11m (36’) high, open to the ramps that wind from the ground floor to the top. They are in the middle of the building so they do not have natural light, but they are pleasant spaces. They might be markets, factories, schools, vertical farms, who knows what people might come up with.
Sky City was a crazy dream and is in many ways, a crazier reality; two years after the building was completed, they are still figuring out what to do with it. Daniel Zhang and his team envision it as a low-carbon answer to the problems of housing:
…in the next 20 years estimated 300 cities will be born, 20% of the world's population will urbanize, that is about another 2 billion people, if we build the conventional way, concrete and steel and sprawling highways and cars, new cities alone would exhaust the carbon emissions budget to keep the planet from warming over the two tolerable degrees as agreed by global scientific communities and the UN.
So they envision a world-wide network of self-reliant SkyCity co-housing projects:
We recognize the need to redefine skyscraper design implementing new technologies, materials, programs, aesthetics and spatial organizations. Along with studies on globalization, adaptability, the digital revolution, environmental impact, and cooperative relations between communities, we see an opportunity to inspire humanity on moving forward on a progressive path. It is a hub that examines the relationship between co-living and community set within the natural world, the skyscrapers and the city.
Check it out and register before July 1 for the SkyCity Challenge.