Chinese prefabs firm builds 57-storey tower in 19 days

The Mini City Sky stands as the world's tallest pre-fabricated building
The Mini City Sky stands as the world’s tallest pre-fabricated building. PHOTO/COURTESY
Broad Sustainable Building (BSB), a Chinese prefab company, has built a 57-storey tower in Changsha, China, in just under three weeks – claiming the title of ‘world’s fastest builder’.

The Mini Sky City, which was built using prefabricated construction techniques, stands as the world’s tallest pre-fabricated building, with a series of 19 atriums, 800 apartments and office spaces for 4,000 staff.

The tower was originally due to be 97 storeys but it had to be scaled back to 57 due to concerns about its closeness to nearby flight paths.

BSB claims that it assembled the entire structure in the space of 19 working days, building upwards at a rate of three storeys per day.

“This is definitely the fastest speed in our industry,” BSB vice-president Xiao Changgeng said, adding that the structure is safe and can withstand earthquakes.

However, it should be noted that in prefabrication, over 95 per cent of the engineering work is completed in a factory – meaning the Mini Sky City was completed before groundbreaking was done on-site.

BSB said it spent four and a half months fabricating the building’s 2,736 modules prior to the actual on-site construction.

Interestingly, the installation of the building was done in two separate chunks “due to inclement weather”, with the first 20 storeys completed last year and the final 37 built from 31 January to 17 February this year.

The firm claims that, in addition to reductions in labour and equipment expenses, modular construction enabled it to it to save 15,000 truckloads of concrete that could have been used in conventional methods.

BSB had in 2012 planned to build Sky City in Changsha, which would have been 202 storeys high and 10m taller than Dubai’s Burj Khalifa, but the project was halted – apparently for political reasons.

Prefabricated building techniques have been used widely for high-rise apartment blocks in developed markets – including Britain and the US – thanks to their ability to slash the time and cost of construction, while eradicating material wastage.

Some critics, however, say the method could lead to cityscapes with excessively uniform architecture.