Heller Manus Architects, San Francisco
Over the past 135 years, skyscrapers have grown increasingly taller, larger, more complex, and more expensive. These projects represent massive investments in our urban cores. The reality is, these enormous, iconic structures are now becoming obsolete due to usage standpoint or the market demands occupancies that they can no longer provide.
But what happens when a structure is never completed and you must renovate before the design is ever fully realized? Such is the case with the high rise at 111 Wacker in Chicago, IL. Originally designed to be an 85-story hotel and residential tower, it was designed and built by the same firm at a prominent location along the Chicago River. The financial crisis hit and financing to finish the building was lost. What was left at the beginning of 2011 was a 28-story shell of a tower with 15 stories of parking and hotel column layouts, no cladding and rusting rebar dowels. A new owner with new ideas and new market demands required a different structure than what was originally designed to make this site financially viable.
This project case-study demonstrates how creative design thinking and smart collaboration can allow a design team to take a deteriorating husk of a structure into a gleaming 60-story apartment building that was a success for all involved. Unique column strengthening details, a post-tensioned transfer slab, very careful selective demolition as well as several other interesting design challenges make this a project worthy of study.