Independent engineering experts say the Sky City concept faces a host of problems, from lift design and fireproofing to the physical compression caused by the monumental weight of the completed building.
An audience “laughed” when Zhang’s plans were first presented at a meeting of the US-based Council on Tall Buildings and Urban Habitat (CTBUH), said David Scott, a structural director at engineering firm Laing O’Rourke.
But now “people understand it’s a much more serious offer”, he said. “I wouldn’t say it’s not feasible... Properly thought through, it will work.”
China’s earthquake-proofing standards for skyscrapers are amongst the world’s strictest, he added, and construction may have been delayed by a mandatory expert review of the project.
CTBUH director Antony Wood said: “I’m still skeptical, but it’s with a massive amount of respect for what (Broad Group) has done so far. I’m not inclined to write it off.”
In the hotel, Zhang — who studied art and first worked as an interior decorator — brandished one of his firm’s egg-shaped smartphones, which can gauge levels of tiny air pollutants known as PM2.5.
It was an attempt to demonstrate his building’s immaculate air quality — although the demonstration was rendered more difficult by the cigarette he had just smoked.
Pollution is a hot-button issue in China, but Zhang still feels victimized and misunderstood.
“In this society, if you try to do something good, no one will believe you,” he said. “Society lacks basic trust, and sees everything good as bad.”