The restoration of Cook County Hospital’s long-vacant main building is shifting into high gear after a newly issued construction permit estimated at $90 million. The work will transform the 345,000-square-foot Beaux Arts structure at 1835 W. Harrison Street into two hotels—a Hyatt House and Hyatt Place—with a combined 210 guest rooms plus additional rooms for medical offices and retail space.

While some initial work, such as exterior scaffolding installation, started soon after the project’s ceremonial groundbreaking in June, the recent go-ahead represents the development’s largest and most significant permit to date. It comes on the heels of another important milestone reached earlier this month when the city’s landmarks commission voted in favor of a historic preservation tax incentive for the massive rehabilitation.

Designed by architect Paul Gerhardt in 1914, Cook County Hospital’s main building was listed on the National Register of Historic Places but has suffered from 16 years of vacancy and decay. The grand brick, granite, and terra-cotta structure was spared from demolition in 2003 when the Cook County Board overruled then-board president John Stroger’s decision to tear the outdated hospital down.

Early this year, a private joint venture known as Civic Health Development Group announced that it secured $135 million in financing for the adaptive reuse project. Architect Skidmore, Owings & Merrill is serving as lead designer in collaboration with Koo Interiors. The dual hotels are expected to open in 2020.

Future phases of the estimated $1 billion Cook County Hospital masterplan call for additional structures comprising a mix of residential, commercial, and medical research use. These yet-to-be-finalized phases will be built on county-owned land located north, south, and east of the former hospital building.

The massive rehab is one of several developments transforming the Illinois Medical District on Chicago’s Near West Side. Other notable projects include the new Cook County Central Campus Health Center, the $300 million mixed-use IMD Gateway, a planned $500 million outpatient care facility from Rush University, the glassy 19-story SCIO apartment tower, and Roosevelt Square’s combination public library and affordable housing development.

Commission OKs preliminary landmark designation for the Cook County Hospital Building, 1835 W. Harrison St. Built in 1914 by Paul Gerhardt, the Beaux-Arts structure is one of Chicago's grandest public buildings. The designation covers all exterior elevations, including rooflines. pic.twitter.com/aGehfhD9jJ — Chicago DPD (@ChicagoDPD) August 2, 2018