Michigan’s Whitmer steps up, signs single-stair reform into law

Gov. Gretchen Whitmer took a big step toward clearing the path for developers to build smaller apartment buildings more affordably.

Whitmer signed Michigan’s single-stair legislation into law this week, a green light for developers to build multifamily housing up to six stories more economically, with a single interior exit stairway.

Michigan housing advocates say the win improves the chances that a broader “Housing Readiness” package they support in the legislature will pass.

“This could propel the momentum that we need to change” the laws to make housing more affordable, Lauren Strickland, Abundant Housing Michigan‘s executive director, told HousingWire TBD.

The single-stair move makes Michigan the latest state to break from a longstanding International Building Code two-staircase requirement for residential buildings taller than three stories. Colorado, Texas and Montana are among the states that have already adopted similar thresholds. More than a dozen others continue to study the change, while a number of city governments have moved ahead with the change.

Tennessee enacted an opt-in law in 2024. Nashville, Memphis, Knoxville and Chattanooga took advantage of it last year.

Washington, D.C., is finalizing its own version. California lawmakers are considering comparable legislation.

Fire officials nationwide tend to come out against these changes, arguing a second staircase gives residents an extra escape route and firefighters a clear path to fight the blaze. Connecticut is a prime example of the political power fire officials wield.

The state adopted reform in 2024 to allow a single-stair building up to four stories, adding just one floor above the previous limit. But that single floor drew opposition from fire and safety officials. They bogged down the rules-and-regulations process to the point that lawmakers repealed the law in February.

Smooth passage

Two related bills advanced through the Michigan Senate after clearing the House earlier this year with bipartisan backing. Whitmer’s signature finalizes a two-tier structure: one law permits single-stair construction in buildings up to four stories. The second extends that allowance to buildings between five and six stories. This second measure takes effect only because the first passed, tying the two together as intended.

The rules will sunset once Michigan’s Department of Labor and Economic Opportunity formally adopts the International Code Council’s own single-stairway standards. That frames the new rules as a bridge measure rather than a permanent break from the model code.

Housing advocates who pushed for the change argue it will meaningfully lower construction costs, particularly for infill projects in dense urban corridors where lot sizes constrain design. A single-stairway layout frees up floor space that would otherwise go toward a second stairwell, letting developers fit more units or larger units into the same footprint.

“It will allow us to build more homes for families of different sizes at lower costs — all on land we already have,” Matt Grocoff, an Ann Arbor-based developer and founder of Thrive Collaborative, said in a statement. “For families priced out of Michigan communities, this law may be the difference between a home that gets built and one that never gets built.”

Still time for more housing reform

The single-stair law stands out as one of the few housing wins on the governor’s desk this year. Whitmer’s agenda is “build, baby, build.”

But the Housing Readiness package, which would loosen parking minimums, lot-size rules and accessory dwelling unit restrictions, has stalled for now. It faces resistance from local governments wary of losing zoning authority, and the Michigan Municipal League’s competing MI Home Program is similarly stalled.

Separately, Whitmer’s proposed Michigan Housing Opportunity Credit, which would stack atop the federal Low-Income Housing Tax Credit, passed the full Senate in June and awaits action in the House Regulatory Reform Committee. Sen. Jeff Irwin has projected the credit could generate more than 2,500 affordable units annually if enacted.

Michigan’s legislative session runs longer than most other states around the country. It is one of the few states with a near year-round session, running from mid-January to Dec. 31.

“We still have time,” Strickland said. “All hope is not lost.”