The tower would be built by Franklin Van Buren LLC and Development Resources, Inc. on a 1.3-acre block bounded by Franklin and Van Buren streets, Congress Parkway and Wacker Drive.

Developers Resources chairman Jim DeRose tells GlobeSt.com construction will take 18 to 24 months, but the start date has not been set. He told the city's plan commission Thursday there is a "strong possibility" construction could begin without pre-leasing.

The West Loop submarket began the year with an 11.8% direct vacancy rate, according to U.S. Equities Realty research. However, the vacancy rate jumps to 18.9% when sublease space is added, according to the firm's figures.

However, parking, rather than the market for DeRose's glass and aluminum, with pre-case concrete, was an issue with the plan commission. At the urging of the Chicago Transit Authority, the developers are proposing 72 parking spaces rather than the 129 called for under the underlying C-7 zoning. The department of planning and development allowed the lower number of parking spaces because of public open space included in the project.

"It's a beautiful building," says 42nd Ward Alderman Burt Natarus, who nonetheless supports the project. "But there's not enough parking."

Fellow plan commission member and department of planning and development commissioner Alicia Berg notes there are public parking garages in the surrounding area, as well as Metra commuter rail terminals and CTA elevated and subway stops.

The office tower would be built on what is now a parking lot. It would offer 2,000 sf of ground-floor retail space in addition to a 5,400-sf plaza with a multi-level water feature with seating.