75 East Wacker Drive, Mather Tower

The 521-foot-high building is sometimes called “The Inverted Spyglass” by Chicagoans due to its highly unusual design, a 21-story octagonal tower atop a more conventional 20-story rectangular “box.” Briefly the tallest building in Chicago at the time of its completion in 1928, it remains the city’s most slender high-rise structure at only 100 by 65 feet at its base. The interior space within the upper octagonal spire contains the least square footage per floor of any Chicago skyscraper. In 2000 Masterworks Development Corporation purchased the structure and undertook a complete restoration. In November 2002, the final phase of the project was initiated when a helicopter lifted the steel framework for a new cupola from a river barge to the top of the tower.

VDA provided full consulting services through construction administration for modernization of five (5) gearless elevators in this 42-story office building.  Constructed in 1926, the building was originally named the Mather Tower after Alonzo Mather, who invented a more humane way to bring cattle to market on rail cars.  is also known at the Mather Tower that was built in 1926, and is also known as the Mather Tower.

The elevators had previously been modernized in 1982 and the later modernization was completed in 2003.

Project Info

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Koenen Associates

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Chicago, IL

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