Supertall 'Sky City' will house 4,400 families in Changsha, China

The developer of the planned new world's tallest building, Sky City, is one step closer to making the colossal structure reality. Broad Sustainable Building has received government approvals to build the 2,749-foot, 220-story tower in Changsha, China. The Building Team will begin site work next month, according to Treehugger.com.

As its name suggests, Sky City is designed to be a fully functional city, complete with residential units for 4,450 families, schools, offices, a hospital, recreational spaces, theaters, hotel rooms, and nearly a million sf of vertical farms. In all, the tower will house 11 million sf of live, work, and play spaces. Apartments will range from 645 sf to more than 5,000 sf.

A six-mile-long ramp will link the entire structure, allowing occupants to move from floor to floor without taking one of the building's 92 elevators. The design also incorporates more than 50 courtyards that will house shared community spaces, such as basketball and tennis courts, swimming pools, and parks.

The program is certainly impressive in size and scale, but the most eye-popping fact about the project is construction schedule. By employing extensive prefabrication, the skyscraper will be assembled in just three months. As Treehugger's Lloyd Alter describes: "The Broad system is based on prefabricated floor panels that ship with everything need to go 3D packed along with it, so they are not shipping a lot of air. It all just bolts together. Broad claims that by building this way, they eliminate construction waste, lost time managing trades, keep tight cost control and can build at a cost 50% to 60% less than conventional construction."

Check out renderings and plans for the project:

Read the Treehugger report on Sky City.

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