Skyscaper chart via CNNGO
In December of last year, Chinese developer Broad Sustainable Building (BSB) constructed a 30-story hotel prototype in 15 days. 360 hours. Seems they were just getting started. The construction company has announced plans to build an 838 meter (2750 feet) tall skyscraper in Changsha, Hunan PR, and they say they'll do it in just 90 days. 2160 hours!
As CNNGO reports, 'Sky City' would become the world's tallest tower, eclipsing Dubai's Burj Khalifa by just 10 meters. While that building took some 5 years to complete, the new superstructure, estimated at RMB 4 million ($628 million), would not only be far cheaper than rival skyscrapers (compared to Burj's $1.5billion price tag and the $2.2 billion Shanghai Tower), but will also employ sustainable building techniques and systems unheard of at such scales. BSB says the 220-story tower, which will offer 1 million square meters of occupiable space linked by 104 elevators, will consist almost entirely of prefabricated modules that will be stacked on site--the key to the neck-breaking construction times that the company is promising. The building will also feature innovations such as quadruple glazing and thick (quake-resistant) exterior walls that will significantly cut down its energy consumption. The company hopes that Sky City will receive the necessary approval to break ground by November of this year, with the project's completion following in January 2013.
A possible rendering of 'Sky City', via Inhabitat