Big Renovations at Big John by Chief Engineer Magazine

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Big Renovations at Big John by Chief Engineer Magazine

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John Hancock Building Chicago

(This article was originally published in Chief Engineer Magazine, The Official Publication of the Chief Engineers Association of Chicago, Since 1934. All text and images in this post are courtesy of Chief Engineer Magazine. Visit the site

It is hard to believe that the John Hancock Building — the iconic “Big John” that symbolizes the Chicago skyline more so than any other building in the Loop — has been gracing the Chicago skyline for more than four decade. The building itself, both inside and out, certainly doesn’t reveal its age; thanks in big part, to the operating engineers who care for and operate the 1,499-foot (base to tip) behemoth.

Construction on Big John began in 1965 and the building was commissioned in 1969. At the time, the building cost $95 million to construct, which by todays standard is a bargain for a 3 million-square-foot structure built on prime real estate. One hundred stories tall above ground, the entire structure is clad in curtain wall aluminum upon a trussed tube steel structure and caisson foundation. Skidmore, Owings & Merrill LLP were the architects for the building, and its structural expressionist style nestles comfortably in a town marked by some of America’s greatest architects.

Bill Casey Able Services
Bill Casey, Chief Engineer, Able Services

What has brought the Chief Engineer to Big John for this issue of the magazine is big news about renovations completed in the structure, and some that are still going on. We caught up with the Bill Casey of Able Engineering, the chief engineer in the John Hancock, who was gracious enough to spare us time to share with our readers what’s new in the building.

The most recent news, according to Casey, centers on the major chiller replacement that was undertaken to modernize mechanicals by scrapping the original chillers and replacing them with eight 525-ton Carriers running on 134a refrigerant. “These new chillers are absolutely great,” Casey said. “Running down to as low as 30-percent capacity, they are still energy efficient and run perfectly.” Anchor Mechanical Inc. performed the work swapping out the old R11 and R114 chillers with the new Carriers. The work began in November 2013 and was completed in May 2014, just in time for the cooling season. Carrier computer software controls the chillers automatically, optimizing run time and maximizing efficiency. While most service and operation is separated between the residential and commercial areas of the building, chilled water produced by the new chillers is provided to all occupants and areas within the structure.

Along with the chiller replacement, a six-celled, 5,000-ton Marley Tower was refurbished in the building, which included replacement of all gearboxes, props, cells and motors. This was another major undertaking that was needed in order to pair state-of-the-art chillers with the best technology available on the condenser side.

Also last year, all 10 of the Precision high-temperature hot-water boilers in the building were rebuilt. The boilers provide heating services for the commercial space within the building that runs from below grade to the 44th floor. The condominium space above the 44th floor is heated electrically on a separate system.

While talking about the mechanicals is always the first and last topic with engineers, we should point out, too, that renovation in tenant space and the Chestnut Street lobby of the building was also completed. The lobby is actually breathtaking, with the addition of a very large reflection pool dominated by a massive, fiber optic-lighted design called Lucent, suspended above the pool and below a reflective ceiling. The result is the reflective illusion of two giant orbs that represent the two hemispheres. The lighting can be adjusted to change colors so a seasonal effect greets visitors who enter the building.

Also recently added were additional exercise machines and space for the indoor health club, along with a yogi room and a new game room that permits company workers to take a break over a game of table tennis, pool or shuffleboard during breaks or, if they prefer, just chill and watch television, or read for awhile.

Casey became Chief of Big John in March 2011. Prior to that, he was chief engineer in the Stone Container Building and Union Station. In his present role he and his two assistant chiefs, Tom Zec and John McHugh, oversee a nine-member crew that keeps Big John running.

In his spare time, Casey is an avid cyclist and keeps a bike at Big John for cycling along the lakefront before or after work. Commuting from his home in Joliet, he prefers to avoid rush-hour traffic by arriving early to work and leaving later for home. A before- or after-work bike run along the lakefront fills any slack time. A father of two, Casey shares his family time with a passion for woodworking, his primary hobby.

Ownership of Big John is split between the many condominium owners occupying the floors above 44, the Hearn Company, which owns most of the commercial space, and other owners who hold deed to smaller sections and aerial space.

Walking outside on our tour, Casey showed us an ongoing project to rebuild and resurface the building garage. The project required the shutdown of half the parking entrance, creating a logistical nightmare that has been managed fairly well by the buildings team. Concrete was removed and new concrete poured along with a new resurfacing that is resistant to road salt. The entire project is scheduled for completion this month.

Finally, Casey showed us another recently completed project that replaced an obsolete Life Safety System with a new Honeywell Notifier System.
We left Big John impressed by the freshness in the look of the structure and the dedication apparent in the people who are entrusted to see the building into the next four decades of its life. We thank Casey and the entire team at Able Engineering for showing us through the facility, and letting us share their story with their fellow chief engineers.

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