Chicago’s rule that most new apartment buildings need two staircases is quietly deciding what kind of housing actually gets built. Architects and housing advocates say the requirement forces long double-loaded corridors and extra stair cores that chew up precious floor area. That design penalty nudges developers toward larger, bulkier buildings on assembled lots instead of smaller, neighborhood-scale infill. The result, they argue, is fewer family-sized units and fewer chances to add "missing-middle" housing in walkable parts of the city.
An opinion piece published May 8 laid out that argument in detail. As reported by Crain's Chicago Business, the column contends that Chicago’s stair-placement and egress rules have become a practical roadblock for small infill projects that might otherwise slide into existing neighborhood fabric.
What advocates want
Local housing advocates and a handful of aldermen are backing a narrow change to the building code that would let certain mid-rise residential projects rely on a single, well-protected stair. Ald. Matt Martin has introduced File No. O2025-0017571 to amend Section 14B-10-1006.3.3 of the code. The proposal has been sent to the Committee on Zoning, Landmarks and Building Standards, according to Chicago Cityscape.
Safety evidence and other cities
Supporters of the tweak point to a growing body of data suggesting that, with modern protections, single-stair designs can perform safely. A February 2025 report from The Pew Charitable Trusts found that contemporary four-to-six-story single-stair apartment buildings with sprinklers had fire-death rates no higher than comparable buildings with more exits. The same analysis estimated construction savings of roughly 6-13 percent for those single-stair projects and noted decades of use for similar designs in cities like New York City, Seattle and Honolulu.
How Chicago's code works
Chicago’s municipal code (Title 14B-10) adopts International Building Code egress standards with local tweaks and sets the number of required exits based on occupant load and travel distance to an exit. The city’s code library spells out the narrow circumstances in which a single exit is permitted. Many R-2 multifamily projects exceed those limits and end up needing a second stairway, which advocates say raises construction costs and trims rentable space, according to the City of Chicago.
What's next for Chicago housing
Backers of the ordinance say this seemingly technical fix could open the door to more small infill buildings and unlock additional family-sized apartments that fit Chicago’s traditional block pattern. Fire-safety organizations, meanwhile, are pushing for strict guardrails on any change, including tight limits on travel distances, mandatory sprinklers and robust smoke control. The proposal will move through the City Council committee process, where developers, neighborhood groups and safety officials are expected to weigh in, and its fate could influence how Chicago tackles missing-middle housing for years to come, per Chicago Cityscape.
