How long does it take to build a 57-storey skyscraper? Only 19 days

A Chinese construction company is claiming to be the world’s fastest builder after erecting a 57-storey skyscraper in 19 working days in central China.The company now has ambitions to assemble the world’s tallest skyscraper, at 220 floors, in only three months, according to the international media.

Broad Sustainable Building, a prefab construction firm, put up the rectangular, glass and steel Mini Sky City in the Hunan provincial capital of Changsha, assembling three floors a day using a modular method.

The record-breaking building is designed to be connected by sky bridges to a larger Sky City complex yet to be completed. This first step in the grand scheme is this mixed-use structure featuring 800 apartments and office space for 4,000 workers with a total of over 185,000 square meters as well as 19 giant atrium spaces.

Video: https://www.youtube.com/watch?v=PyxwgLYbAk0 

Producing many of the component parts in advance in factories, including entire truss systems, saves

time and energy on site and also reduces pollution associated with busy construction sites and cast-on-site concrete.

Its builders at BSB estimate a reduction in output of carbon dioxide by 12,000 tons thanks to these techniques as well as other environmental benefits, including a decrease in dust and particulates in the air around the building site.

“With the traditional method they have to build a skyscraper brick by brick, but with our method we just need to assemble the blocks,” the company engineer Chen Xiangqian said.

Modular methods have been used for high-rise apartment blocks elsewhere, including in Britain and the US. Some critics say the method could lead to cityscapes with overly uniform architecture.

Broad Sustainable Building spent four and a half months fabricating the building’s 2,736 modules before construction began. The first 20 floors were completed last year, and the remaining 37 were built from 31 January to 17 February this year.

The company is awaiting approval for its 220-floor building, called Sky City, which will also be in Changsha.