Monadnock Building

The Monadnock Building is a 16-story skyscraper located at 53 West Jackson Boulevard in the south Loop area of Chicago. The north half of the building was designed by the firm of Burnham & Root and built starting in 1891. The tallest load-bearing brick building ever constructed, it employed the first portal system of wind bracing in America. Its decorative staircases represent the first structural use of aluminum in building construction. The south half, constructed in 1893, was designed by Holabird & Roche and is similar in color and profile to the original, but the design is more traditionally ornate. When completed, it was the largest office building in the world. The success of the building was the catalyst for an important new business center at the southern end of the Loop.

The building was remodeled in 1938 in one of the first major skyscraper renovations ever undertaken—a bid, in part, to revolutionize how building maintenance was done and halt the demolition of Chicago's aging skyscrapers. It was sold in 1979 to owners who restored the building to its original condition, in one of the most comprehensive skyscraper restorations attempted as of 1992. The project was recognized as one of the top restoration projects in the US by the National Trust for Historic Preservation in 1987. The building is divided into offices from 250 square feet to 6,000 square feet in size, and primarily serves independent professional firms. It was listed for sale in 2007.

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