A Chicago window is a large fixed glass panel flanked by two narrower sashes of the same height, filling a structural bay. The large pane is a single panel of plate glass, and the flanking elements are vertical double-hung sash windows with no dividing muntins. The fenestration was first used by architect William LeBaron Jenney in the 1884 Home Insurance Building, and immediately after by several of the Chicago School architecture firms such as Holabird and Root in their Marquette Building (Chicago), Daniel Burnham's Fisher Building (Chicago), and Louis Sullivan's Carson Pirie Scott department store. The window design was made possible by advances in glass-making technology and steel structural framing, and became a defining feature of the Chicago school style. The design offered both abundant natural light and practical ventilation. Projecting oriel bays are a common variant of the Chicago window, as seen here in the Reliance Building (1895) by Burnham and Root.
Chicago window in the context of Chicago Building
The Chicago Building or Chicago Savings Bank Building is an early skyscraper, built in 1904–1905. It is located at 7 West Madison Street in Chicago. Designed by the architecture firm Holabird & Roche, it is an early and highly visible example of the Chicago school of architecture.
The building's features characterize this style through the use of large "Chicago windows", metal frame construction, distinctive bays, and terra cotta cladding. The combination of the north side projecting bay windows, and the east side rectangular "Chicago windows" with movable sashes is representative of the two typical Chicago school window types. The building is prominently located on the southwest corner of State Street and Madison Street, with visibility increased by an offset in the alignment of State Street.
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