John Hancock Center
875 North Michigan Avenue
Chicago, Illinois
Designed by engineer Fazhur R.
Khan and architect Bruce Graham, Big John had to be carefully stabilized against powerful
wind loads and its own height (100 stories), resulting in the distinctive X-shaped
crossbracing. The external crossbracing also conveniently freed up the interior space from
columns, allowing for flexible office arrangements.
Because of this construction Big
John is unexpectedly light. 50 lb/sq. ft is the typical structural steel weight in
high-rise Chicago buildings; the John Hancock weighs in at a mere 29.7 lb/sq. foot
(although it uses a total of 46,000 tons of steel). This allowed it to be constructed for
the cost of a conventional 45-story office building.
Big John is a powerful symbol of
the city; as Blair Kamin notes in the AIA Guide to Chicago, it "best exemplifies the
Chicago tradition of combining bold structural advances with brawny architectural
form." Such a tradition you could call your own: at the time of writing Big John is
on the market, as John Hancock begins to divest itself of its real estate holdings.
Christy Rogers, 1998
How to visit
The first forty-one floors are
office, parking, and commercial; the remaining upper floors are condominiums, an
observatory, a restaurant & bar, and broadcast facilities.
The observation deck is open
from 9am to midnight. The ride up costs $8. Call +1 312 787 3800 for more information. If
you would rather spend the $8 on a drink, skip the Observation Deck (although I
wouldnt, it has wonderful historical information about the city) and go up one more
floor to the bar. Better have a strong stomach though; that elevator is quick.