To grasp the enormous dimensions of the Shanghai Tower, try this simple exercise:
Take the 1,018-foot U.S. Bank building in downtown L.A. — the highest U.S. building west of the Mississippi — and double it.
Take the $1-billion budget of the Korean Air skyscraper now rising at Wilshire and Figueroa and triple it.
And take the square footage of the L.A. Convention Center and multiply it by six.
The Shanghai Tower is China's tallest building and the world's second-highest, behind only the Burj Khalifa in Dubai.
The 121-story structure — now on the verge of opening after almost seven years of construction — would be a monumental achievement for even the most experienced architectural firms specializing in so-called supertall buildings.
Yet for San Francisco design firm Gensler, which beat out three other finalists with its twisting, asymmetrical cylinder-within-a-cylinder design featuring soaring park-like atriums every 15 floors, the commission was truly a long shot.
Though Gensler is a global firm, now with 46 offices around the world, the company had only about eight years of experience in China at the time and essentially no track record with extremely tall buildings.
"If you had a portfolio of … many, many tall buildings, you'd say we would have had a much higher probability of getting" the commission, said Dan Winey, head of Gensler's Asia practice. "But at the time, the biggest project that we had done was [the 54-story hotel and condo tower at] L.A. Live.… This is 2 1/2 times that."
Despite the odds against the firm, Gensler's striking design won over Chinese officials seeking a symbol of the city's aspirations to be a world financial center.
At the same time, its eco-conscious and public-space elements have attracted global interest as a possible markers for a new era of ultra-tall structures that aim to be a bit kinder and gentler both on the environment and the people who work, shop, eat and sleep in them.
The building will be LEED Gold certified, a designation by the Leadership in Energy and Environmental Design rating system for green buildings.
It has a gray water recycling system and 270 wind turbines to generate electricity to power exterior lighting. The two-layer glass facade functions like a Thermos, reducing energy costs and creating space for a series of "sky gardens" where office workers and hotel guests — and even members of the public — can relax, eat and socialize.
"This is a pretty significant tall building simply because of what it emphasizes.... It is expressive but it cares about its environment," said Daniel Safarik, director of the China office of the Council on Tall Buildings and Urban Habitat. "It is a turning point."
Winning the design contest was one thing; getting the skyscraper to soar into the clouds above the Huangpu River was something else. One of the most complex buildings ever engineered, the Shanghai Tower's guitar-pick-shaped form rotates 120 degrees as it tapers.
A groove known as a strake helps the structure resist and shed the typhoon-force winds that are known to batter the city of 23 million — a design element that allowed for lighter materials, saving an estimated $58 million in costs. The entire exterior glass skin is hung on steel cables.
"Figuring out the turn and taper and constructing this wall that's hanging out in space — that was really difficult. How does it fit, how is it watertight?" Winey recalled. "Many times I thought, 'This is not going to work.' We put it through tests simulating a typhoon, and the initial mock-ups leaked all over the place."
On a blustery day in late May, workers were still toiling to seal the structure as rain intruded in various spots from the entryway up to the observation-deck floor.
"This building, essentially, is a prototype," said Marshall Strabala, a former design director with Gensler who now has his own architecture firm and continues to consult on Shanghai Tower. "Sometimes you discover a leak and you need to plug it."
To reach the top of the structure, visitors hurtle skyward at more than 55 feet a second in one of the tower's 106 elevators. It takes almost a minute to reach the 121st floor.
There, thrill-seekers will be able to venture onto an outdoor observation deck for bird's-eye views of the Shanghai Tower's two superstructure neighbors: the ornate, 88-story Jinmao Tower, opened in 1999, and the wedge-shaped 101-story World Financial Center, opened in 2008 and often called the bottle opener because of the cutout on its upper floors.
"Jinmao references China's past; it's a stainless steel pagoda. And WFC is contemporary, Western, clean-cut and hard-edged," said Jun Xia, the design principal for Gensler on the project. "Shanghai Tower is about the future, but it has to be in harmony with the other two, so this has a softer form."
For the last three decades, China's population pressures, land scarcity and massive shift from agriculture toward urban living have pushed the country to the forefront of skyscraper construction. Today, 35 of the world's 100 tallest buildings are in mainland China. By 2020, that number will rise to 59, according to the Council on Tall Buildings.
Private developers are behind some of the Chinese super-towers, but quasi-governmental or state-run entities are the builder-operators of many of the tallest structures, and Shanghai Tower is no exception.
That, in effect, changes the economics of these buildings because these long-term landlords can make different choices about materials and design.
"A speculative [built] office building is less likely to be green than an owner-occupied one," Strabala said. "A typical American developer wants payback in three to five years, 10 years at the most. Here, the client will run the building for the next 50 years, so they'll invest in systems that might cost more upfront but start to pay for themselves after five or even 10 years."
Winey said Shanghai Tower is an exercise in making a vertical city, with the park-like atriums open to the public.
"There are 21 14-story city parks or atriums that comprise the heart of the building," he said. "What [U.S.] building would have 21 14-story atriums? … Normally the public is locked out" of such amenities.
"The absence of a completely hard-nosed profit motive can lead to more interesting buildings," Safarik said. "These buildings do have something to teach us — most of these buildings are being done by U.S. and U.K. architects who can't do this kind of work at home, where the tastes are more conservative.
"China is breaking the mold over and over again."
Gensler isn't the only California company involved with the Shanghai Tower. Edgett Williams Consulting Group in Mill Valley, Calif., designed the building's elevator and escalator systems, and SWA Group in Sausalito, Calif., was the landscape architect. Los Angeles real estate manager CBRE Group Inc. has been hired for property management.
Apart from the main tower design, Gensler's Los Angeles office designed the retail and entertainment podium at the base of the skyscraper. About two dozen members of Gensler's L.A. team worked on the project, with six to eight people spending about a year in Shanghai and others working remotely.
Over the last decade, many U.S. architecture firms, particularly from Chicago and New York, also have put their stamp on the skylines of dozens of Chinese cities.
With China's economy now slowing and Chinese firms seeking real-estate deals abroad, the relationship with U.S. architecture firms is shifting into a new phase.
"We have a lot of Chinese investors coming to Los Angeles and San Francisco," said Andy Cohen, one of Gensler's two co-chief executives. "That capital is helping to reshape our cities, which has frankly been really great.... It's completely reversed."
Chinese developer Greenland, for instance, has commissioned Gensler to work on the Metropolis project in downtown Los Angeles. Other Chinese developers, including Wanda Group and Hazens Investment that recently announced projects in California, are similarly looking to U.S. firms that have done work in China to design their new buildings stateside.
"Now, it's not just one way, but it's coming both ways," Cohen said. "It's been an interesting flip."