During the renovation, the exterior of the building was covered on three sides with trompe-l'œil murals by Richard Haas.
[3] On the south face, Haas evokes two Louis Sullivan creations: the Golden Arch from the World's Columbian Exposition Transportation Building, and the circular window of the Merchants' National Bank in Grinnell, Iowa.
Beneath the arch, Sullivan, Daniel Burnham, John Wellborn Root, and Frank Lloyd Wright stand together.
[2][4] A "reflection" of the Chicago Board of Trade Building also appears in the painted windows between these two features.
[1] On the north face, another set of painted windows contain a fake reflection of Adolf Loos' unused design for the Tribune Tower, which Loos had envisioned as a large column-like structure.