A Chinese construction company is proposing to build the world’s tallest building in astonishing record time.
According to Gizmodo, the Broad Sustainable Building (BSB) Company has boasted it will erect a 2,749-foot building within 90 days, once it gets the go-ahead from the Chinese Government.
Lots of experts, not surprisingly, are dubious. They point out that the current “world’s tallest,” the Burj Khalifa located in Dubai, is 2,719 feet tall and took about five years to build.
Nevertheless, BSB has some impressive building chops. For example, in 2010 BSB constructed a 15 story hotel in just 48 hours, according to Wikipedia. 2011 saw the completion of a 30 story hotel, in just 15 days and a 6 story dormitory that was built in just 5 days. All three of these “lightening construction” buildings are apparently fully operational and safe.
BSB spokespersons have given mixed signals regarding the schedule for the proposed building, which is to be located in the city of Changsha, and dubbed Sky City. At one point, some media reported the project would take 210 days - or a little faster than one floor per day for the 220 story skyscraper. Most recently the company amended that timetable to 90 days start to finish, once government approval is secured.
Speculation on the start date ranges from late November to sometime in January 2013.
To give an example of the scale of the proposed BSB construct; if one took New York City’s first skyscraper, the Woolworth Building, and balanced it on the uppermost spire of the Empire State Building, and then put the famous UN Building on top of both, it would approximate the height of Sky City.
BSB specializes in factory-made skyscrapers. By prefabricating most of a skyscraper it aims to reduce the time, cost and environmental effect of construction. BSB intends to license its technology worldwide and currently has 6 franchises in China and is expanding the number to 150 worldwide.
Wikipedia notes that BSB's plan is to assemble 95 percent of the building in its factory and then move it floor by floor to the actual build site. Sky City will have total floor space of 1.2 million square meters. At an estimated cost of about $1500 per square meter, Sky City would be considerably cheaper than the Burj Khalifa ($4500 per square meter).
Lacking access to detailed plans, some architects have expressed doubts that a modular design would have the stiffness to withstand the wind loads imposed by such a height, without unacceptable amounts of sway, or that the building could be built without high-strength concrete, whose curing time would impede a rapid construction
Present cost estimates set by BSB are about $628 million, compared to Burj Khalifa, which set its owners back about $1.5 billion. Both Sky City and the Burj are described as mixed use buildings, featuring both residence and business suites. The Burj offers about 900 luxury apartments, while Sky City is expected to house some 30,000 residents from both high and low income communities.
BSB says Sky City will be able to sustain earthquakes of a 9.0 magnitude and be resistant to fire for "up to three hours," as well as be extremely energy efficient thanks to advanced insulation, heating and air conditioning technology.
Regarding the name, a web search reveals that there is already a Sky City in Jersey City, N.J., checking in at a relatively modest 48 stories high. There’s also a casino in Las Vegas and a cocktail lounge in Augusta, GA among the numerous locations claiming the moniker.