CHICAGO (CBS) — Aldermen have backed a zoning change for the iconic Thompson Center downtown in an effort to help the state sell the property to a private developer.

The City Council Zoning Committee on Tuesday approved a proposal from Ald. Brendan Reilly (42nd) to upzone the Thompson Center to effectively double the amount of space that could be built on the site at 100 W. Randolph St., allowing for more than 2 million square feet of space.

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The state plans to sell the building and relocate state employees who work there to a newly-purchased office building at 555 W. Monroe St.

Reilly said Gov. JB Pritzker requested the zoning change as the state begins the process of seeking potential buyers, who might seek to replace the Thompson Center entirely, or add a skyscraper to the site.

The alderman said his predecessor, Ald. Burton Natarus, downzoned the Thompson Center site while it was still under construction in 1981, effectively cutting its development rights in half compared to the surrounding blocks. Reilly said that zoning change has left the Thompson Center out of compliance with city zoning rules ever since.

Pritzker put out a request for bidders to buy the Thompson Center earlier this month, and Reilly said restoring the building’s original zoning would make it more attractive to potential buyers.

“This zoning amendment is the important first step that we need to take in order to restore the original zoning rights to the property so that the state of Illinois can market the property for sale to a private interest,” Reilly said.

Reilly said the building costs the state $17 million a year for maintenance and operating costs.

“Taxpayers can no longer afford this building,” Reilly said.

The governor’s office said deferred maintenance and delayed improvements to the building have caused the cost of repairing the Thompson Center to more than $325 million. That cost could balloon to $525 million by 2026.

Reilly noted, because it houses government offices, the property is also tax exempt, costing Chicago taxpayers more than $20 million a year in lost property tax revenue.

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The alderman said any new development or redevelopment of the Thompson Center site after it’s sold would still be subject to approval by the Chicago Plan Commission and the city’s normal zoning review and approval process.

The zoning change now goes to the full City Council for a vote as soon as Wednesday.

Meantime, responses to the state’s request for bids to purchase the Thompson Center are due by 3 p.m. on Aug. 16. A copy of the state’s request for proposals is available on the General Services Illinois Procurement Bulletin at www.bidbuy.illinois.gov. Additional information the Thompson Center and its amenities are available at www.illinois.gov/ThompsonCenter4Sale.

Officials expect to complete the sale by April 2022.

The 17-story building at 100 W. Randolph St. has long been criticized as an overly expensive and inefficient home for state government offices in Chicago.

When it opened in 1985, the great massive open atrium inside and its floors of open offices were meant to pay tribute to transparency in government – the inspiration for architect Helmut Jahn – but the building’s design made it extremely expensive to operate.

With its single-paned glass walls providing insufficient insulation in summer and winter, the Thompson Center costs taxpayers a fortune to heat and cool.

Drainage issues led to the rusty deterioration of some of the building’s pillars, and as stone cracked and fell, unsightly scaffolding was placed around the building for extended periods.

Jahn was killed earlier this month when he was struck by two vehicles while riding his bicycle in Campton Hills, a Kane County suburb near St. Charles.

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His death has brought more urgency to preservationists’ efforts to save the Thompson Center from the wrecking ball as the state moves forward with its plan to sell the building.

CBS 2 Chicago Staff