Monadnock Building

The Monadnock Building (historically the Monadnock Block; pronounced mə-NAD-nok) is a 16-story skyscraper located at 53 West Jackson Boulevard in the south Loop area of Chicago, Illinois, United States. The north half of the building was designed by the firm of Burnham & Root and built starting in 1891. At 215 feet (66 m), it is the tallest load-bearing brick or masonry building ever constructed. It also employed the first portal system of wind bracing in the United States. Its ornamented staircases represent the first structural use of aluminum in building construction. The later 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 (23 m2) to 6,000 square feet (560 m2) in size, and primarily serves independent professional firms. The north half is an unornamented vertical mass of purple-brown brick, flaring gently out at the base and top, with vertically continuous oriel windows projecting out. The south half is vertically divided by brickwork at the...