The top of the building is a modified mirror-image of the bottom, with diagonal trusses holding the roof and freeing the upper floors from interior columns.
This design was dropped in favor of the revised plan for 111 South Wacker which was built in 2005.
The lobby was designed as a round glass enclosure at the base of the stem, leaving room for a plaza with a large artwork.
The structure would have required only 14 new caissons, an unusually low number for a building this size.
The tower would have narrowed slightly in the middle, with a 2-story space split between mechanical systems and common areas such as conference rooms.
The high podium was designed for 2 main reasons: to minimize the quantity of low-rise offices with inferior views; and to utilize the caissons of the U.S. Gypsum Building which are set in from the site's perimeter as that skyscraper was turned 45° to the street.
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