Council on Tall Buildings and Urban Habitat
Young Professionals Tour Medical Tower Under Construction
September 12, 2013
See more about the Young Professionals Committee
CHICAGO - The Northwestern Medicine Outpatient Care Pavilion is a 25-story, 975,000 square-foot (90,580 square-meter) new-build facility within the dense Northwestern University Medical Center complex just north of the Chicago Loop. Designed by Cannon Design, it is comprised of 10 floors of reinforced-concrete parking garages and retail, with 15 steel-framed medical floors above, rising to a total of 385 feet (117.5 meters).
Overall view of the building from the ground. View from the roof of the Northwestern Medicine Outpatient Care Pavilion tower, 18th floor terrace.
On September 12th, the CTBUH’s Young Professionals Committee (YPC) was treated to a tour of the under-construction building, led by J.J. Tobolski, engineer at Thornton Tomasetti, the building’s structural engineering firm, and Eric Engstrom, senior project manager for Lend Lease, the shell-and-core contractor.
Tour attendees examine level 10, the mechanical floor.

The YPC visitors were able to tour the ground-floor drive-through / drop-off area, the parking garage, the 10th-floor mechanical rooms, the 12th-floor surgery suite and the 18th floor, which will serve as a large conference and meeting area. The transition between the “high-intensity” surgery and imaging floors from 10 through 17, to the “low-intensity” office floors from 18 to 24 is marked by a significant setback in the building frontage, facing south along Ontario St. The primary cladding of the building begins to change from precast concrete to steel curtain walls at this level.

Tour attendees were briefed and shown technical drawings of the Pavilion at the project office.
The setback area was originally contemplated as an inaccessible green roof. But as construction progressed, the project team realized that the great potential of the wide outdoor surface area with a view of downtown, and it is now being converted into a terrace.
Before anything like that could happen, the team would be using its tower crane first to complete concrete work on the top floor, and last to hoist MRI equipment through a hatch in the setback roof. The tower crane was to be disassembled by late September, and all enclosure finished by late October.

The most impressive and most developed portion of the building was the 10th-floor mechanical room, where man-sized ventilation ducts run through the diagonals of story-deep steel transfer beams supporting 15 medical floors above. A half-dozen van-sized chiller units filled the floor, and multiple horizontal pipe layers were suspended from the ceiling.  Several of the steel truss members comprising the transfer beams were Grade 65 shapes, and had to be custom-rolled in Luxembourg and shipped the previous fall, before the St. Lawrence Seaway froze and greatly limited alternate transport options, Engstrom said. The required tolerance was less than 1/16” (1.58 mm).
Concrete is hoisted to the construction site.

Other significant constraints include the construction project’s immediate proximity to the Northwestern Memorial Hospital emergency room. The Outpatient Pavilion project involves the construction of one tunnel and two bridges to other medical center facilities, but their erection cannot interfere with emergency vehicle operations. The entire project must halt construction during the Chicago Marathon in early October, and during the hospital’s busiest day – the Lollapalooza rock festival in Grant Park.

After the tour, a social networking event was held for tour participants.

The Outpatient Pavilion is scheduled to open in Fall 2014.

Tour attendees gather for a group photo on the building's roof.