IBM Building
This is the last and tallest office building designed by
Ludwig Mies Van Der Rohe. The superbly proportioned tower
with its precisely detailed curtain wall achieves the elegant
simplicity characteristic of Mies' work during the last decades
of his life. The refined simplicity belies the complexity
of the site. IBM obtained a K shaped plot, bisected
at grade level by a railroad spur. Initially a U shaped
structure was planned, but the city agreed to eliminate
part of Wabbash Ave so that the building could be rectangular.
The tower is 52 stories high and has a curtain wall of
dark aluminium and bronze-tinted glass. The bays of the structural
steel skeleton are 30ft wide and 40ft long. The mechanical
systems of the building are extremely sophisticated,
in part because of the controlled environment needed for
housing computers at the time.