Tuesday 22 December 2015

Willis Tower: Illinois' greatest metal building

Countless skyscrapers adorn the Chicago skyline, with the Aon Center, CNA Center and Prudential Plazas towering above the Windy City's residents. Yet nowhere in this world-renowned capital - or anywhere across the state - are there any metal buildings Illinois more profound than the steel monolith that is the Willis Tower.

Standing at a colossal 1,451 feet, with 108 stories overshadowing its competitors on all sides, this spectacular feat of architecture once held the illustrious title of tallest building in the world. It now has to make do with merely the second tallest in the United States, while sitting just outside the top ten worldwide in 13th place.

Better known by its previous name, the Sears Tower, the initial design came from characteristically humble beginnings, having been inspired by nothing more than a package of cigarettes. Before becoming a landmark in its own right, the purpose of the building was to house its original owners' hundreds of thousands of employees who, up until that point, had been spread across the city.

Built by architects Skidmore, Owings and Merrill, the eventual design pioneered the use of structural engineer Fazlur Rahman Kahn's bundled tube structure. Never used in metal buildings Illinois could boast about before, this model resulted in the skyscraper being built around nine square tubes, each the size of a separate building in its own right. Kahn's success was to inspire architects for years to come, with the current world's tallest building at the Burj Khalifa adopting his techniques.

What made the building's construction even more astounding was that it achieved such an epic feat at a low price. At $150 million, it would have cost the equivalent of $800 million nowadays. A handsome cost maybe, but compared to a 21st Century project like the Taipei 101 it was a bargain, as the latter cost in excess of $2 billion. It even weighed up well against the other major buildings of its time: despite containing more space, it still cost less per unit area than the Empire State Building.

Millions visit its viewing deck every year, yet given its prominence on the screen even those who haven't will probably have seen the sights anyway. From Ferris Bueller and friends watching the streets of Chicago ("I think I can see my dad") to featuring in background shots in Transformers: Dark Side of the Moon, the building has a long history of appearing on the big screen. Rather cheekily, I, Robot chose to relegate it to second place in the metal buildings Illinois ranks, with the fictional United States Robotics Building surpassing it in height. Get more info.

Now home to a thriving community of businesses, the Willis Tower stands today as a hub of creativity, a hive of innovation and a timeless architectural masterpiece. A landmark for tourists and a cultural symbol for locals, it is an iconic sight for all to see, while allowing its visitors to stare out across the vibrant Chicago horizon. There is no building, metallic or otherwise, more grand in the whole of Illinois.