Case Study / Blue Cross Blue Shield | Chicago
- 800,000 SF Vertical Expansion
- 2.2 Million SF Total
The Blue Cross Blue Shield project was the first of its kind. JBC built an additional 800,000 square feet on top of an existing 1.4 million square foot building, which remained fully occupied with 3,800 people during the 3.5 year construction program.
The Blue Cross Blue Shield vertical expansion was an extraordinarily complex construction project. The expansion, which employed over 350 tradesmen from 22 local unions, was completed on-time, despite losing 120 days due to inclement weather delays, within budget, and with a high degree of finished construction quality.
JBC overcame several unique construction challenges associated with building on top of an existing structure. These hurdles included the erection and maintenance of two luffing tower cranes with 160-foot booms at the 30th floor, the maintenance and continued operation of 24 existing cooling towers at the 29th level, and the extension and continued operation of three existing service elevators to the 52nd floor.
In order to meet the demands of the ambitious project, JBC developed a rigorous safety program, which included a gear-driven interior skip-hoist that did not utilize counterweights, a multi-functional safety canopy at the building’s main lobby, and a structural steel safety platform extending 12 feet from the face of the structure, which wrapped around the entire perimeter of the building at the 32nd and 33rd levels.