Willis Tower looking up
|Antenna spire||527 m (1,730)|
The Willis Tower is a skyscraper in Chicago, Illinois. Sears, Roebuck and Company paid for the building to be built in August 1970. It was called the Sears Tower until 2009. The building was finished in 1974. The Willis Tower was the tallest building in the world from 1974 to 1996. It has 108 levels, and from the ground to the roof it is 442 m (1,451 ft) tall. The tower was designed by Fazlur Khan and Bruce Graham.
History[change | edit source]
Before the Willis Tower was completed, the tallest building in the world was the World Trade Center. In 1996, the Petronas Twin Towers in Kuala Lumpur, Malaysia became the world's tallest buildings. The Willis Tower is still the tallest building in the world from ground to pinnacle because it has two television antennas on top of it.
Sears executives decided that the space they would immediately occupy should be efficiently designed to house their Merchandise Group. But floor space for future growth would be rented out to smaller firms and businesses until Sears could retake it. Therefore, those floor areas had to be designed to a smaller plate, with a high window-space to floor-space ratio, to be attractive and marketable to prospective lessees.
Design[change | edit source]
Smaller floorplates required a taller structure to yield sufficient square footage. Skidmore architects proposed a tower with large 55,000-square-foot (5,000 m²) floors in the lower part of the building, and gradually tapered areas of floorplates in a series of setbacks, which would give the Sears Tower its distinctive look. The design was inspired by an advertisement for a package of cigarettes.
Height[change | edit source]
From the ground to the top of the taller antenna is 527 m (1,730 ft). The building leans about 4 inches (10 cm) towards the west due to its slightly asymmetrical design, placing unequal loads on its foundation. The Willis Tower is the thrid the tallest skyscraper in North America. The building is so tall that the observatory elevators in the tower are the fastest in the world at 1600 feet per minute, so that they can reach the sky deck faster. With clear weather, four states are viewable up to 50 miles away: Michigan, Indiana, Illinois, and Wisconsin.
On November 8, 2013, a debated sparked between architects across Chicago and New York City debating about the height of the One World Trade Center. They're saying that there's a possibility that the Willis Tower might actually be the taller than the One World Trade Center. On November 12, it was confirmed that the One World Trade Center is taller than the Willis Tower.
References[change | edit source]
- "Willis Tower - The Skyscraper Center". Council on Tall Buildings and Urban Habitat. http://skyscrapercenter.com/chicago/willis-tower/.
- The History Channel; Modern Marvels (series); episode: The Sears Tower
- "Willis Tower Fast Facts". CNN.com. November 14, 2013. http://www.cnn.com/2013/10/03/us/willis-tower-fast-facts/index.html. Retrieved December 8, 2013.
- "Willis Tower, One World Trade Center compete for bragging rights as America's tallest skyscraper". CBS News.com. http://www.cbsnews.com/8301-505263_162-57611461/willis-tower-one-world-trade-center-compete-for-bragging-rights-as-americas-tallest-skyscaper/. Retrieved November 9, 2013.
- "One World Trade Center taller than Willis Tower". Examiner.com. http://www.examiner.com/article/one-world-trade-center-taller-than-willis-tower. Retrieved November 12, 2013.
Other pages[change | edit source]
Other websites[change | edit source]
|Wikimedia Commons has media related to: Willis Tower|
- Official website
- Chicago Skydeck website
- Emporis.com - Willis Tower
- SkycraperPage.com – Willis Tower
- A view from 103rd floor of the tower