#the marvels—and mistakes—of supertall skyscrapers

[quotesfrommyreading]

Like many cutting-edge innovations, supertalls can behave unpredictably. In strong winds, occupants have reported water sloshing in toilet bowls, chandeliers swaying, and panes of glass fluttering. The architect Adrian Smith, who has designed numerous supertalls, contends that you’re in supertall territory not just when you hit 300 meters, but when you build so high that you get into “potentially unknown issues.” And, he acknowledges, there are “still mistakes being made.”

Supertalls aren’t necessarily good neighbors. Their shadows can reach half a mile, and they can magnify the winds at street level, churning the air into high-speed gusts as far as three blocks away. Many New Yorkers consider the city’s proliferating supertalls at best an eyesore—“Awful Waffle” is one nickname for 432 Park Avenue, a luxury condominium that looks like a strip of graph paper stuck on the Manhattan skyline. At worst, they’re considered nonsensical constructions that exacerbate the city’s affordable-housing crisis, contribute to climate change, and stand as totems to inequality. An earlier generation of supertalls mostly housed offices, but today many of New York’s supertalls are designed to serve as homes for the superrich—“the modern-day castle, if you will,” says Stephen DeSimone, a structural engineer who’s worked on supertalls in the city. “You’re living amongst the sky, like the rest of the world isn’t good enough.”

Supertalls have made even fans of tall buildings wonder whether we’ve built too high, for too few—and finally gone too far. Staring up at them from the dark, blustery sidewalk, it’s hard not to wonder: Is there anything to love?

  —  The Marvels—And Mistakes—Of Supertall Skyscrapers

[quotesfrommyreading]

High-rises have become so ubiquitous, it’s easy to forget what a triumph it is to build even a humdrum office tower. For millennia, our ancestors inched slowly but steadily toward the clouds. Archaeologists have called the Tower of Jericho, completed about 10,000 years ago, the “super-skyscraper of its day.” It reached a grand total of 28 feet. Around 2,600 B.C., the Great Pyramid of Giza broke records when it hit 480 feet—less than half the height of the Eiffel Tower—and humans took nearly 4,000 years to go higher. (The spire of an English cathedral eventually surpassed the Great Pyramid in 1311, but only by about three floors.)

From the Tower of Jericho through the Industrial Revolution, there was basically one way to go high: stone. Traditionally, masonry walls supported a building’s weight and structure, which curtailed their height. Going taller required thicker walls, which, beyond a certain point, risked monopolizing floor space and squeezing tenants into sunless cavities. The New York World Building, briefly the city’s tallest in 1890, had some walls wider than a garbage truck.

Steel skeletons sent us higher, to mixed reviews. As skyscrapers began appearing on the New York skyline at the turn of the century—back when skyscraper meant any building with more than a dozen floors—observers warned that these buildings were a “menace to public health and safety” that would surely collapse. After a building spree in the ’70s, the urban historian Dolores Hayden criticized skyscrapers as “phallic monuments” that had been forced on cities by unchecked capitalists and stood as emblems of “architectural rape.”

And yet for as long as we’ve been finding new ways to build taller, we’ve usually felt uneasy about doing so. The biblical story of the Tower of Babel is an early example of our altitude-lust going hand in hand with regret over our hubris: After that supertall scraped the heavens, God supposedly punished humans by taking away our shared language and scattering us around the globe.

Some cities tried to restrict skyscrapers after watching them transform New York’s skyline in the early 20th century, and lots of places still have laws meant to limit buildings’ height. Bali restricts buildings to the approximate height of a lanky palm tree, and Washington, D.C., imposes a height maximum based on street width. Even China, after a two-decade supertall spree, recently imposed a height limit of sorts, outlawing the construction of buildings over 500 meters—slightly taller than the Steinway Tower outside my window.

But humans keep hungering to go higher. “Boy, it is innate in us,” says Bill Baker, a structural engineer at Skidmore, Owings & Merrill who played a key role in designing the Burj Khalifa. During the latter half of the 20th century, the record for the world’s tallest building crept up approximately 16 stories; in the past 20 years, it’s shot up nearly 90 floors. We’ve never witnessed buildings rise so much, so quickly. From high-rises, we’ve stretched to supertalls and even megatalls (double the height of a supertall), and engineers are already discussing “ultratalls” that would take us higher still. Over the past few decades, new combinations of materials like microsilica and fly ash (a residue that results from burning coal) have made concrete steroidally strong—“10 times as strong as the stuff down on the sidewalk” in some cases, Baker told me—and steel has gotten sturdier too, all of which has helped spur the supertall boom. Advances in elevator technology—such as ultra-strong, lightweight cables and algorithms that efficiently consolidate passengers—have also helped buildings stretch. But engineering advances aren’t the main reason supertalls keep growing. “It’s a message of power,” the developer Don Peebles, who in 2021 proposed a 1,600-foot tower in Midtown Manhattan, told me. “It’s not trying to blend in. It’s trying to stand out.”

The symbolism attached to height is no doubt part of what makes tall buildings so divisive. A century ago, many New York churchgoers felt a moral duty not to let offices rise over their houses of worship, whose spires had dominated the city’s skyline for decades. In 1923, rallying around a cry to “restore the cross to the skyline!,” a Methodist congregation unveiled plans for a skyscraper church that would be the tallest building in history, topped with a glowing, revolving, five-story cross. But the building never reached its full grandeur, topping out at a little more than three stories as new, taller office towers continued to overtake the skyline.

The evolution of our nation’s tallest structures can arguably be divided into three broad phases. First the tallest buildings were built in honor of deities, then commerce, and now: billionaires.

  —  The Marvels—And Mistakes—Of Supertall Skyscrapers

[quotesfrommyreading]

Yet supertalls not only ascend; they also sway, flutter, vibrate, bend, and lean. Often a lot. Chicago’s Willis Tower—which is more than 50 feet taller than 432 Park—can move up to three feet in strong winds. If you were to look down at the spire of a tall building during a windstorm, you’d see that it careens left, right, and around, like an inebriated giraffe.

All of that motion can cause people to feel a little drunk themselves. Occupants of tall buildings have, in high winds, reported nausea, distractibility, difficulty working, and fatigue, though researchers report that skyscrapers “rarely, if ever, induce vomiting.” As winds howl, buildings can moan like creaky container ships, or clatter like subway cars. “No Realtor would ever give a potential tenant a handbook that explains how these buildings behave, because they wouldn’t buy them, probably,” says Peter Weismantle, the director of supertall-building technology for Adrian Smith + Gordon Gill Architecture, which designed Central Park Tower.

And yet some motion is safe and normal, and often goes unnoticed. In fact, evolving approaches to handling high winds are a big reason contemporary supertalls have gotten to be so numerous, and so thin.

Tall buildings get celebrated as gravity-defying, but it’s their defiance of the wind that should inspire awe. Imagine a strong wind blowing south over Central Park. The wind hits the supertall and pushes it backwards into a lean, then causes the structure to sway as the gust picks up and dies down. Wind can get stronger at higher altitudes and intensify as it whips off neighboring high-rises, so what registers as a gentle breeze on the fifth floor may give way to howling on the 45th. Wind barreling around the supertall creates turbulent eddies on the building’s exterior that cause the structure to wag from side to side. These are the accelerations that tenants are most likely to perceive, and slender supertalls are even more susceptible to them.

Developers know they cannot control the wind. What they can do—and this is an industry term—is confuse it. For this, they recruit a wind-whisperer like Derek Kelly. Kelly, an engineer with the consulting firm RWDI, is a garrulous Canadian who, when I asked about superslims, told me the company has worked on “almost every building you see out your window.”

Take 432 Park. Once the developer had an early design for the new tower, Kelly began by making the proposed supertall—a solid, skinny, square column—super small. Kelly and his colleagues 3-D-printed a knee-high model of the building, and stuck it into a miniature Midtown Manhattan, complete with dozens of neighboring high-rises that can affect the windscape at 432 Park’s site. They put the model buildings on a turntable inside a wind tunnel, then subjected them to smoke and powerful fans. RWDI adjusted the wind tunnel’s settings to mimic Manhattan’s gusts and rotated the tiny neighborhood in 10-degree increments to get a baseline measurement of how the proposed supertall would sway, absorb winds careening off other structures, and shift the wind around it—all of which remains too complex to accurately predict with algorithms, Kelly said.

Even a 10-story building will move, and most of us can handle our homes wiggling about five milli gs (a measure of acceleration) in any direction. Early tests on 432 Park’s prototype revealed poor aerodynamic performance. Rafael Viñoly, 432 Park’s architect, said in a 2014 lecture at the Skyscraper Museum that tests on one version of the building revealed the supertall would dance 30 milli-gs—just shy of the threshold found to “cause some occupants to lose balance,” according to research published in the International Journal of High-Rise Buildings. “If you’re standing here, your cup of tea moves,” Viñoly said at the lecture, rocking his lectern back and forth to demonstrate. He called the experience of 30 milli gs “absolutely frightening.”

When problems like these arise, Kelly brings the developer and the design team to RWDI’s wind tunnel for a “shaping workshop.” Architects and engineers tweak the shape of their supertall, 3-D-print new versions, then put each one in the wind tunnel to see how much it moves. “For some of these buildings in New York,” Kelly said, “we’ve done 12, 16 versions in an afternoon.”

The decorative flourishes on a supertall that seem ornamental can be key to diffusing the suction-filled whirlpools that sway a building as wind whips around its sides. You could notch the corners, like on Taipei 101, which resembles a towering stack of gifts. You could twist the building, like the Twizzler-esque Shanghai Tower. You could taper it to look like the tip of a paintbrush, like the Lakhta Center, or cut out sections to let wind blow through it, like the Shanghai World Financial Center, which is nicknamed “The Bottle Opener.” 432 Park’s designers decided to make it more porous: Every 12 stories, there are two “blow through” floors with cutouts for windows, but no glass.

But can you comfortably host a dinner party on a blustery evening? To try to experience for themselves how hospitable 432 Park would be, Viñoly and his colleagues traveled to the Marine Institute in Newfoundland to be jostled around inside its simulator—a 20-ton steel ship’s bridge mounted on hydraulic pistons and surrounded by screens. Typically, ships’ crews use the simulator to practice for encounters with icebergs and roiling seas, but for the past 15 years, the institute has hosted supertall designers who want to double-check their work before they build. On these occasions, the institute covers up the nautical instruments, projects a city skyline on the screens, lugs in a forest-green sofa, puts water-filled glasses on a wooden kitchen table, and hangs a glass chandelier. Once the supertall’s team of designers settles in, the room starts rocking and rolling to mimic what tenants will feel on a windy day, during a strong gale, or during a once-a-century hurricane. At 432 Park, the blow-through floors alone wouldn’t settle the building, so the developers ultimately installed two tuned mass dampers—a pair of 600-ton counterweights between the 86th and 89th floors that can move 11 feet, to offset the supertall’s sway.

That’s the goal, anyway. New cars and planes go through rigorous testing before hitting the assembly line, but each supertall is essentially a prototype. “We’re going into production on one-offs every single time with the hopes that we get it right,” the structural engineer Stephen DeSimone told me. If you could crawl out over the side of 432 Park and look down at the facade during a windstorm, “you’d have not one but two heart attacks. Because the thing does move,” Viñoly said in his 2014 lecture. “Don’t tell the tenants that.”

  —  The Marvels—And Mistakes—Of Supertall Skyscrapers

[quotesfrommyreading]

We’re living through the birth of a new species of skyscraper that not even architects and engineers saw coming. After 9/11, experts concluded that skyscrapers were finished. Tall buildings that were in the works got scaled down or canceled on the assumption that soaring towers were too risky to be built or occupied. “There were all sorts of symposiums and public statements that we’re never going to build tall again,” one former architect told The Guardian in 2021. “All we’ve done in the 20 years since is build even taller.”

There are skyscrapers, and then there are supertalls, often defined as buildings more than 300 meters in height, but better known as the cloud-puncturing sci-fi towers that look like digital renderings, even when you’re staring at them from the sidewalk. First supertalls were impossible, then a rarity. Now they’re all over the place. In 2019 alone, developers added more supertalls than had existed prior to the year 2000; there are now a couple hundred worldwide, including Dubai’s 163-story Burj Khalifa (a hypodermic needle aimed at space), Tianjin’s 97-floor CTF Finance Centre (reminiscent of a drill bit boring the clouds), and, encroaching on my sky, Manhattan’s 84-floor Steinway Tower (a luxury condominium resembling the love child of a dustbuster and a Mach3 razor).

Some supertalls have an even more futuristic designation: superslim. These buildings are alternately described as “needle towers” or “toothpick skyscrapers” (though not every superslim is a supertall). Early superslims shot up in Hong Kong in the 1970s, though lately they’ve become synonymous with New York City; four supertall superslims loom over the southern end of Central Park in a stretch of Midtown dubbed “Billionaires’ Row.” Building engineers, like judgy modeling agents, have varying definitions of superslim, but they usually agree that such buildings must have a height-to-width ratio of at least 10 to 1. To put that in perspective, the Empire State Building (one of the world’s first supertalls, completed in 1931) is about three times taller than it is wide—“pudgy,” as one engineer described it to me. Steinway Tower is 24 times taller than it is wide—nearly as slim as a No. 2 pencil, and the skinniest supertall in the world. (The developer’s official name for the building is 111 West 57th Street.) These superslim buildings—and supertalls generally—have relied on engineering breakthroughs to combat the perilous physics that go with height. A 2021 article in the journal Civil Engineering and Architecture declared: “There is no doubt that super-tall, slender buildings are the most technologically advanced constructions in the world.”

  —  The Marvels—And Mistakes—Of Supertall Skyscrapers

[quotesfrommyreading]

Who pays to live in the sky? It’s not easy to find out. According to public records, lots of the units in Midtown’s residential supertalls were purchased by anonymous limited-liability companies, many of them with names implying a bored exhaustion with shuffling money around. Apartment 40A at 432 Park belongs to an entity called 432Park40A LLC. Other LLCs read like AOL screen names: Ashmonster, Cupcake Lily, Bigappleview, Euclidean Taco Distance. Rarely do you come across an actual person’s name—one perk of buying via LLC is the privacy—though some digging reveals buyers who are connected to sports, tech, finance, real estate. One buyer served time for running an illegal gambling ring. Before they sold their place, Jennifer Lopez and Alex Rodriguez had an apartment at 432 Park. Many units have owners but not dwellers: This fall, four properties for sale at 432 Park advertised that they’d never been occupied.

That includes the penthouse. “Never before lived in,” beams Ryan Serhant, a former star of Million Dollar Listing New York and one of the brokers who has represented the apartment, in a home tour he posted on YouTube in 2021. “A true one of one. A world marvel.”

“I don’t really see us as selling real estate,” Serhant told me. “I sell a transfer of enthusiasm and excitement and brand.”

Could I come see this world marvel?

Absolutely not, Serhant’s PR consultant informed me on his behalf. The penthouse’s owner—reportedly a billionaire Saudi real-estate developer—hadn’t okayed visits to the apartment from journalists. Moreover, Serhant wouldn’t even discuss 432 Park, I was told.

This didn’t seem unrelated to a lawsuit that 432 Park’s condo board has filed against the building’s developer. The plaintiffs claim that the building is riddled with more than 1,500 defects that have led to leaks, cracks, electrical explosions, and elevator shutdowns that trapped people for hours—as well as “horrible and obtrusive noise and vibrations,” including clicks, creaks, and a trash chute that thunders “like a bomb.” Also—pull out your tiny violins—breakfast in the private restaurant is no longer free. (The developer denied these allegations in court filings, saying they were “vastly exaggerated,” and maintaining that 432 Park is, “without a doubt, safe.” Lawyers for the developer acknowledged that, when the building had first opened, its “sophisticated symphony of systems needed to be fine-tuned,” and said the board had denied the access needed to do necessary work.)

Supertalls have generated a litany of complaints that make them sound like evil X-Men in their ability to wreak havoc on a city. The allegations against them include unleashing hazardous ice (a man reportedly suffered a “major injury” when ice slid off Central Park Tower), heating cities (the United Nations blames tall buildings generally for contributing to potentially dangerous urban temperatures), monopolizing the sky (critics claim that supertall developers have exploited zoning loopholes, unfairly stretching their towers by cramming in extra floors under the guise that they house mechanical elements), and obliterating the sun (a “Sunshine Task Force” has investigated the shadows that supertalls cast on Central Park). Sun beaming off skyscrapers’ glass facades has apparently resulted in so-called death rays strong enough to melt a van’s dashboard and singe a pool-goer’s hair.

The Jeddah Tower is a one-kilometer-tall building planned for Jeddah, Saudi Arabia, and would be the world’s tallest structure. Fortunately, its architects added a large canopy to the base of the supertall’s curved glass facade. One of the goals: to keep it from frying pedestrians like ants under a magnifying glass.

  —  The Marvels—And Mistakes—Of Supertall Skyscrapers