Assemblymember Alex Lee Introduces Bill on Single-Staircase Reform

Assemblymember Alex Lee introduced legislation to unlock new housing by reforming the building code for multifamily apartments. AB 2252 paves the way for constructing mid-rise, single-stair housing, which opens up opportunities to build homes in urban areas where larger, dual exit apartments aren't feasible.

Currently, California and much of the U.S. requires two stairway exit routes in multi-unit apartments above three stories tall. Despite advances in fire mitigation technology, the U.S. is still among a handful of nations with the strictest stairway requirement in the world. Eliminating the second stairwell will make it easier to build apartments, reduce construction costs, and create new architectural design possibilities, while maintaining the highest standards of fire safety.

Single-staircase reform allows developers to build more compact buildings in small, urban lots. These apartments can reduce construction cost by an estimated 6-13%. Further, building apartment units around a single stair creates new options for unit sizes and layouts.

AB 2252 directs the Department of Housing and Community Development to propose building standards for single stairway multiunit residential apartments of up to six stories.

"Stairway requirements can have a profound effect on what does and does not get built in our neighborhoods," said Assemblymember Alex Lee. "Many countries worldwide have already legalized mid-rise apartments with one staircase that maintain robust, modern fire prevention measures. By unlocking previously undevelopable properties, AB 2252 will bring much-needed multifamily housing to our urban neighborhoods."

U.S. cities like Seattle and New York City allow for midrise apartments with a single staircase and have demonstrated a proven track record of safety. In New York City, for instance, a new report shows that fire fatality rates in modern single-stairway four-to-six-story buildings were similar to other residential buildings over a 12-year period. In addition, the researchers found that none of the fire fatalities in four-to-six-story buildings in New York City or Seattle could be prevented by a second stairway.

AB 2252 builds on the growing momentum of single-stair reform. 7 states passed legislation on single-stair reform in 2025. Most recently, Culver City became the first California municipality to legalize single-stair apartments of up to 6 stories. The ordinance also requires enhanced safety measures, such as a cap on the number of units per floor to ensure quick and safe evacuations. Other required measures include increased access for firefighters' aerial ladders and smoke control technology. The cities of San Jose and San Francisco are studying the issue as well, joining a handful of states nationwide in exploring potential reforms.

AB 2252 will be heard in the Assembly Housing and Community Development Committee on April 22.