Council on Tall Buildings and Urban Habitat
 

Blue Cross Blue Shield Building Tour

October 21st, 2009
Report written by Nathaniel Hollister, CTBUH Assitant

BCBS Tower
.
Blue Sheild Blue Cross Building
. In December of 2007, yet another Chicago high-rise construction site became active in the downtown area. This particular site, however, had one entirely unique and challenging characteristic; it was located over 400 ft. above the street on top of an existing tall building. The Blue Cross Blue Shield Tower, preeminently located at the northern edge of Millennium Park, is the site of an ambitious and historic building project. This project aims to add 24 floors to an existing, completed and fully-functioning Chicago high-rise. Such a large scale addition has never before been attempted in Chicago’s 125 years of skyscraper history, and has very few comparable examples internationally.

As such, this project was an obvious location for one of the CTBUH Pre-Conference Technical Tours, and on the afternoon of October 21st, the tour took place. As conference guests, many of whom had traveled directly from the airport, gathered in the expansive lobby of the Blue Cross Blue Shield Tower, it seemed a strange place to prepare for a technical construction tour. The lobby bustled with the day-to-day activities of any occupied Chicago high rise; highlighting in the minds of the guests the tremendous obstacles faced by the design and construction companies in adding 24 floors to a fully-functioning building.

Once the guests had arrived and passed through security, they were shown to a lower-level conference room and introduced to their tour guides: Jim D’Amico, Vice President of the John Buck Company, Joseph Dolinar, Partner/Project Director of Goettsch Partners, and Lou Rossetti, Senior Project of Walsh Construction. Together, these guides were able to provide the tour with professional explanations of the architecture, economics, and construction of the Blue Cross Blue Shield project.

.
Tour Guests begin to gather in the lobby Guests enjoy a video introduction in the conference room

The guests were then shown a introductory video on the history of the project and Lou Rossetti gave a short presentation on the project. Rossetti explained to the guests that, during the original design of the tower in the 1990’s, the eventual expansion was discussed and fully planned. The designers at Goettsch Partners planned the building in two phases; Phase 1, the concrete-core, 30 floor building completed in 1997, and Phase 2, the steel-core 24 floor expansion begun in 2007. Rossetti complimented the thoroughness with which the original designers planned the eventual addition to the building. This planning included among other things the sizing of the original building structure for the loads of a 54 floor building, atrium space for additional lifts required by more floors, and attention to materials used and their expected availability in the future. These and other factors not only significantly simplified the expansion project, Rossetti made it clear that without this prior planning Phase 2 could not have been economically feasible.

Rossetti also described some of the major challenges faced by the design and construction teams due to the unique nature of the project. In order to assemble the tower crane, for instance, pieces for a 17-ton derrick had to be transported through the building using a freight elevator. Once the 17-ton derrick was pieced together, it was used to assemble a 35-ton derrick. This, in turn, was used to construct the tower crane.  Another challenge which Rossetti mentioned was that of working in a fully-occupied building. Walsh Construction had gone to great lengths so as to not disturb the work atmosphere in the Blue Cross Blue Shield Tower. He explained some of the systems the construction company had employed to minimize the interference between materials and construction personnel and the building employees. This included the scheduling of some specific, potentially distracting tasks on the weekend, and transportation of personnel through separate construction lifts. Thus far, Rossetti reported, the interference prevention systems had been extremely effective.

Upon completion of the introduction presentation, the tour through the building was begun. The first stop for the conference delegates was the 30th floor. As the guests stepped off the crowded lift, they were brought into a fantastic, open, 30 foot high space. This level, Rossetti explained, was at one time, the highest extent of the Blue Cross Blue Shield Tower. The original cooling towers were located at this level. Walsh Construction, in order to allow the cooling towers to continue to serve the building during construction, left a 3-story gap from the 30th to the 33rd level. Once the new cooling towers were in place, 24 floors above the originals, the old cooling towers were removed, and cladding applied to the 30th level.

.
Guests admire the expansive space on the 30th floor
Lou Rossetti speaks about the 30th floor and its past and future use

This immense space has been designed as a conference center for the building. As the tour guests were guided to another lift to bring them to the 52nd floor, they filed past one of the unfinished atriums in the building. This allowed curious guests a fantastic view up into the heart of Phase 2. The atrium extended to the final floor of the building, providing views of some twenty floors. After a quick photo shoot of the atrium and an explanation of the layout of the buildings atriums by Joseph Dolinar, the tour moved on to the lift. This brought the tour to the 52nd floor, which will become the highest occupiable floor in the building. The tour guests quickly scattered around the perimeter of the building, enjoying amazing views of downtown Chicago. The Blue Cross Blue Shield Tower’s location at the northern edge of Millennium Park provides fantastic, unobstructed views to the south. To the north the guests were able to examine the recently completed Aqua Tower. When the Blue Cross Blue Shield Tower tour guests had fully examined the views of Chicago, they were taken back down through the building to the conference room for the conclusion of the tour. There closing comments were made, and the tour guides were thanked and presented with a gift from the CTBUH.

.
Peering up into the heart of Phase 2 Guests enjoy the views from the 52nd floor

The tour successfully revealed the challenges and complexities faced by the design and construction teams during Phase 2 and the tour guests were impressed with the innovative solutions employed in the completion of the project. The Blue Cross Blue Shield Tower provided conference delegates with an entirely unique example of a tall building project. Moreover, the combined experience of Jim D’Amico, Joseph Dolinar and Lou Rossetti provided the tour guests with extremely informed answers to all questions. The CTBUH would like to thank the John Buck Company, Goettsch Partners and Walsh Construction for making this tour possible. A special thanks is extended to Jim D’Amico, Joseph Dolinar and Lou Rossetti for an entirely enjoyable and informative tour.

Blue Cross Blue Shield Tour Guests

Attendees: Sergio Steve Curro, Illinois Institute of Technology; Chaitanya Davda, Navbharat Estate Developments; Vinesh Davda, Navbharat Estate Developments; James Fortune, Fortune Consultants Ltd.; Kendo Hahn, Dow Corning Korea Ltd.; Wui Junill, Teng & Associates, Inc.; Leo Le Brun, French Trade Office; Inyong Lee, DeStefano + Partners; Mike McMains, Chicago Architecture Foundation; Rajah Venkatraman, Fortune Consultants Ltd.; Bob Randall, Apogee / Viracon; Geralt Siebert, Universitat der Bundeswehr Munich; Barbara Siebert, Ingenieurburo Dr. Siebert; Aleksandar Zeljic, Gensler; Moshe Tzur, Tzur Architects International Ltd.; Orna Tzur, Tzur Architects International Ltd.


.
Picture Gallery
Click an image below to enlarge.
. . . .
Overall View
.
Base of Tower

Guests gather in lobby

View of lobby

Guests view presentation
30th floor

Guests expolore

30th floor

Lou Rossetti
talks with guests
Tour guests

View of atrium
View of atrium
Typical floor
Facade detail
Enjoying view of 52nd floor