Revisiting China's Lost "Sky City"
Revisiting China's Lost "Sky City"
When revolutionary ideas solve the wrong problem
About a decade ago, an innovative Chinese company known for building pre-fab skyscrapers announced its intention to build the world’s tallest building in just 90 days. Called “Sky City” the megastructure would be so large that residents would rarely need to leave, a literal city in the clouds. Its modular construction technology was touted as a solution to the high cost of housing. But alas, Sky City was solving the wrong problem and never saw the light of day…or did it?
The Sky City
The company behind Sky City, Broad Sustainable Building, or BSB, has a track record of success, having built dozens of large skyscrapers in record time using pre-fabricated components. Indeed, they became “Youtube famous” in 2011 for building a 30-story tower in just 15 days, and a 15-story hotel in only six days the year before.
Sky City was an ambitious leap, an entire mini-city contained within a single building. At some 1.05 million square meters and 838 m / 2,749 ft tall, Sky City would be large enough to house some 30,000 residents within its 202 stories. It would come complete with a shopping mall, schools, office space, a hospital, a roof garden, an amusement park, a sports facility, and a 1000-guest hotel.
At an expected cost of $1.46 Billion or $1500 per square meter, Sky City would be considerably cheaper to build than comparable megastructures. This would largely be owing to its innovative construction technology that would have seen 95 percent of the building’s construction done off-site in factories.
The construction site would be prepared and foundations poured, meanwhile, prefabricated sections of the building, essentially steel and concrete blocks, would be built offsite to be hauled to the work site and assembled like legos. Once the structure was finished, it would take an additional 4 months to complete internal furnishing.
Above all, Sky City was an attempt to illustrate how innovative construction technologies could make housing more affordable for the masses. So what happened to Sky City?
What Happened?
Ground was broken and the foundations poured, but the project became mired in controversy. Ultimately, the local government refused to provide a building permit due to environmental concerns. As a consequence, BSB was not able to begin building the structure and the foundation instead became a fish pond. The world moved on and wrote Sky City off as a publicity stunt. But that is not quite the end of the story.
BSB did complete Sky City, albeit only the lower portion of the building at another location. Called “Mini Sky City” the 57-story/204m complex was completed in just 19 days. It contains 800 apartments and office space for 4000 people. It was meant to test the technology and techniques required to build its larger sibling. Unfortunately, since Sky City is off the table, the “Mini” is the most we will ever see of this ambitious project.
Solving the Wrong Problem
Prefabricated or modular construction techniques and 3D-printed housing have a long history of false starts and lost promises. These concepts have thus far failed to catch on at scale. This is likely due, in part, to unique building codes at every construction site, making “mass production” of housing exceedingly difficult.
Further, while these technologies offer the potential to reduce the cost of housing, they will only help at the margins, for they are solving the wrong problem. In many parts of the world, housing costs have detached themselves from physical construction costs. As I discussed here, housing is now primarily a supply and demand issue, and the marginal cost of construction is of relatively little importance.
The solution to the high price of housing is less a technical challenge than it is a political one. This challenge can be solved by easing zoning regulations and converting property taxes to Land Value Taxes, allowing the market to meet the demand for housing. Nonetheless, modular construction technology is surely imaginative and may ultimately prove useful in niche scenarios. Sky City dreamed big, but perhaps just a little too big.