Communication with a neighboring project, careful choreography of deliveries and a constant eye to adjacent the Chicago Transit Authority's Green Line tracks have played key roles in the construction of the $94.6 million CTA headquarters building at 567 W. Lake St. in the West Loop.

Seth Gudeman, superintendent for general contractor Power Construction of Schaumburg, said that construction of the 20-story 180 N. Jefferson St. apartment across the street from the 12-story, 418,000-sq.-ft. CTA building presented logistical challenges.

"Our project is a big footprint building on a small [41,000 sq. ft.] site," Gudeman said.
With El tracks to the north and existing buildings to the east and south, the only option for crane placement was the sidewalk area on the site's west side. But the high-rise apartment going up across the street also had no option but to place their tower crane on the street.

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"We had two tower cranes right across the street from each other. We had to do a lot of coordination. Both projects were required to have luffing booms to avoid each other when swinging, and we were not allowed to swing over the El tracks with or without a load. We almost treated our buildings like one site with two cranes on it."

Joel Gettleman, vice president of Chicago-based Fred Teitelbaum Construction Co., general contractor of the $40 million apartment building, said things went smoothly. "Everyone was on the same page all along," he added.

Gudeman said Power's crane was positioned slightly off-center, to the south, to facilitate coordination with Teitelbaum.

"It took a lot of planning," he added. "When you move cranes around, you have maximum load capacity at a greater distance. By sliding to the south we flirted with maximum loads for penthouse picks."

The CTA will depart the Merchandise Mart, where it had been located for decades, to seek to realize cost savings. The move is projected to reduce the agency's annual operating expenses over a lease alternative.

Materials Issues

The detailed planning extended to delivery of materials as well.

"The job has one entrance, out along Jefferson where the sidewalk would be," Gudeman said. "Trucks stage there for the tower crane and back in the same entrance to feed the man and materials hoist." All deliveries are scheduled in advance.

Because the CTA building has no basement and the site had housed a surface parking lot prior to construction, no earth retention or involved sitework was required.
But the neighboring El tracks required constant attention.

"There were always concerns of debris drifting from our building onto the tracks," Gudeman said. "We put up mesh safety nets on the north elevation from the concrete slabs to our safety rails.

"We had to stay sensitive to the debris issue and coordinate stocking of materials with that in mind." The third of the building closest to the tracks was not used to house materials.

Greening the CTA

The structure will be topped by a green roof, an environmental feature of the sort championed by Mayor Richard Daley, not a roof garden for occupant use.

"The green roof was a requirement of the CTA from day one," said Doug Grover of Fifield Cos., the Chicago-based developer. "The CTA felt it was a necessary component and incorporated it into the project, so we needed to make sure the roof of the building could sustain the weight of the added materials and top soil."

From a construction perspective, the roof presented other concerns.

"The roof consists of a hydro-tech membrane with multiple built-up components," Gudeman said. "It includes drainage mats, filter fabrics, soil and different natural grass plantings.

"It's a pretty complex installation. The roofers have to work hand-in-hand with the landscaper."

He said that constructing a system like this on top of a building requires quick action.
The mats have to be put in place first, followed immediately by dirt, which has to be lifted by crane to the rooftop.

"The dirt has to come up right behind the mats, because the mats can potentially blow away," Gudeman said.

He said one of the benefits of installing a green roof, which was landscaped by Chicago-based Wolff Clements and Associates, is that the living plants create an ecosystem that significantly decreases the amount of runoff that would otherwise enter the city's sewage system.

Build-out of Floors

The final build-out of the floors will present more obstacles.

"The biggest challenge we have is in regard to doing a turnkey building for the CTA," Grover said. He said this building will centralize the CTA offices under one roof. Those offices that are being relocated from the Merchandise Mart must be in the new building on Oct. 1 when their Merchandise Mart lease expires.

In order to accommodate the CTA's schedule requirements, the building will be turned over in sections for phased occupancy. The CTA will begin occupying lower floors while work continues on upper floors. Sections of the building are scheduled to be turned over on Oct. 1, Oct. 15 and Nov. 1.

"We will be dividing up the elevators, leaving two elevators that we can access from back-of-house areas with equipment and personnel while people are using their nice new lobby," Grover said. He added that temporary partitions will also be erected to separate occupants from ongoing construction.

"We are also working hard to accommodate their vendors, security, telephone and computer people," he said. "We have to leave them time to complete their work, too."