The design for what would be North America's tallest building has changed— again. The twisting 2,000-foot tower by Santiago Calatrava, dubbed the Chicago Spire, maintains the overall height that was unveiled in July 2005, but the 550-foot broadcast antenna that was to cap 115 floors has been replaced by usable square footage on 150 floors, according to an evolving series of renderings released since December. The initially proposed 300 apartments and 150 hotel rooms are now conceived as at least 1,300 condominium units.
The changes seem to be the result of financial necessity. Local developer Christopher Carley of the Fordham Co. sold the prime lakefront site and striking design to Dublin, Ireland–based Shelbourne Development Ltd. last year. Shelbourne founder Garrett Kelleher retained Calatrava and the now familiar twisting spire motif, but the December unveiling of a new, bulked-up design drew derisive comments from the local architecture community.
Within weeks, a new and seemingly slenderer model and rendering were circulated among certain Chicago players. An official, even more refined scheme was presented during meetings with the general public and neighborhood community groups in late March, when the developer revealed that the tower's form would continue to be honed during design development. Chicago-based Perkins+Will is the associated architect.
The most recent schemes place the tower on a broad plaza above seven levels of underground parking. A soaring glazed base surrounded by seven piers resembles a faceted, transparent egg. The once-blunt roof now tapers to a dome; as many critics have noted, this gives the entire tower the unfortunate form of a sex toy.
At press time, the new plans were scheduled to be presented to the City Plan Commission on April 19. If approved, zoning review would likely take another three to four weeks, with subsequent approval by the city council expected shortly thereafter. Kelleher is targeting May for groundbreaking, despite the unlikely scenario that the approval process will be complete by the end of this month.
Doubts remain regarding financing. Kelleher has released no pricing for the units and does not intend to do so until the third quarter of this year—well after the proposed start of construction. Overall costs are expected to soar above the $1.2 billion announced for the initial scheme and will likely require the priciest apartment listings in the city. A planned 40-month construction schedule would see the building's completion no earlier than late 2010.