Following up on their incredible feat of constructing a 30 story hotel in 15 days, Broad Sustainable Building ("BSB") reports it is planning construction of a 220 story building to be constructed in Changsha, in the Hunan Province.   The building will be called Sky City, and will be serviced by 104 elevators.

BSB claims its planned construction will be approved by the Chinese government, and will represent another breakthrough in sustainable and economical construction.  Sky City is expected to consume a fifth of the energy required to build a conventional building due to the company’s ‘unique construction methods’, such as ‘quadruple glazing’ and ‘15-centimeter-thick exterior walls for thermal insulation’.  It is also expected to cost much less to build than conventional construction — $628 million as compared to $1.5 billion to construct the 828 m Burj Khalifa — the world's current tallest building.