THE SKINNY ON
SKYSCRAPERS

New York’s decision to build skyward was based on necessity and technological invention…and driven by a heavy dose of ego.

FIVE-STORY LIMIT

By the 1820s, New York was the economic capital of the country. The city’s growing businesses needed office space, but even back then, midtown Manhattan real estate was pricey. So owners wanted taller buildings—one way to get more useable space onto a small, expensive lot. But building high presented several problems.

The most obvious was gravity. Climbing up and down more than five or six flights of stairs made everyday business tasks—or just getting to the office—difficult. Plus, many of the practical needs for a skyscraper hadn’t been developed yet: reliable central heating, indoor plumbing, and lighting systems.

And then there was the problem of the foundation. In the early 19th century, anyone who wanted to construct a building more than 10 stories high had to use the same technology that was around during the time of the pyramids: They’d need a huge foundation with thick walls to support the weight of the building. A 16-story building built of brick or stone, for instance, required walls that were at least six feet thick. To soar 20 stories or more, a building would have needed an enormous foundation that might not fit into a narrow midtown lot. And its walls would have to be so thick that they’d take up most of the square footage on the lower floors—there would be hardly any room left in it for office space. Tall commercial buildings seemed completely impractical, so in the mid-1800s, the Manhattan skyline boasted very few buildings more than five stories high.

“Skyscraper” is an old sailors’ term for the uppermost sail on a ship.

UP, UP, AND AWAY

That didn’t last long. In 1852, inventor Elisha Graves Otis from Yonkers created the first safety brake for elevators. The elevator had been around for centuries, evolving from crude pulley systems to ones that worked with hydraulics, but they carried mostly freight because they were dangerous and difficult to control. Otis’s brake, which prevented the elevator from falling if a cable snapped, made them safe for passengers. Five years later, Otis installed New York’s first elevator in a department store on Broadway. It worked so well that its architects began to think vertically. By 1875, New York developers had begun constructing 10-story office buildings with elevators. The late 1800s also saw improvements in the electric light bulb, central heating, plumbing, and the telephone. Together, these amenities made it at least possible to construct an extremely high building.

But the foundation was still a problem—one that an Englishman named Henry Bessemer and an American, William Kelly, were trying to solve. Steel was a strong, light metal that could eliminate the need for thick walls, but during the mid-19th century, making steel required an enormous amount of coal to heat the metal. The process was extremely costly and time-consuming, and steel was so expensive at the time that forks and knives made of the metal cost more than ones made of gold.

But then, in 1856, Bessemer (who later bought out his competitor Kelly) figured out how to mass-produce steel: by using a furnace that blew air through molten iron. The air added oxygen to the burning process, and oxidization removed impurities from the iron; all that remained was high-quality steel. The Bessemer process needed less fuel, and tons of steel could be produced quickly. Prices tumbled, and steel suddenly became available for building projects.

THE FIRST SKYSCRAPERS

By the 1880s, New York’s buildings were being constructed in an entirely new way. Much of Manhattan rests on granite rock, so crews dug down to that bedrock, which wouldn’t shift. On that solid foundation, builders set footings—large concrete and steel pads that spread out to absorb the weight of an enormous structure.

Vertical steel columns then were attached to the footings, connected to each other by horizontal steel girders. Diagonal beams could be riveted to the girders and columns for extra support. The columns, girders, and beams formed a rigid steel cage that was strong but also lightweight. To keep that light cage from swaying in the force of strong winds, vertical concrete cores were installed. Sometimes the cores anchored the center of the building around the elevator shafts; other times, concrete was poured around the vertical columns near the building’s perimeter. Either way, the heavy concrete helped stabilize the structure and anchor it against wind pressure.

Speedy delivery: Iron girders milled in Pittsburgh were still warm when they arrived at the Empire State Building construction site.

These steel frameworks were so strong and absorbed so much of a building’s weight that there was no longer a need for thick outer walls. Instead, their outer walls became known as “curtain walls,” because they weren’t supporting the structure and hung like curtains on the inner frame. They would then be fitted with glass that brought in light and views.

THIS MEANS WAR!

Most people agree that the first skyscraper was the 100-foot tall Tower Building, which opened in 1889 on a narrow lot at 50 Broadway. A decade later, the Park Row Building became the tallest office building in the world, rising to 391 feet. In those early days, many New Yorkers worried about skyscrapers toppling—especially when the triangular-shaped Flatiron Building opened on Fifth Avenue in 1902. The Flatiron was 285 feet high and only six feet wide at its narrowest point. Its shape seemed so unstable that gamblers placed bets on when it would fall. (It’s still there.)

As the city got used to skyscrapers—and they proved to be safe—“height wars” pushed buildings skyward. Owning one of the world’s tallest buildings wasn’t just a great advertising tool—it was also a status symbol. Discount store millionaire F. W. Woolworth decided that he wanted to own the tallest, most beautiful skyscraper in the world. In 1910, he commissioned the Woolworth Building. It opened three years later and rose to a staggering 760 feet, designed in a Gothic style that gave it the nickname the “cathedral of commerce.”

In 1931, the Woolworth Building was eclipsed by the even taller Empire State Building. At more than 1,200 feet high, the Empire State Building remained the world’s tallest building for more than 40 years until the World Trade Center climbed 100 feet higher. Since the 1970s, other cities have built skyscrapers even taller—today, the world’s tallest building is the Burj Khalifa in Dubai (2,717 feet). But it all started in New York.