On October 23, San Francisco’s Board President Aaron Peskin introduced groundbreaking legislation aimed at revising building codes. The changes intend to safely modify certain stairway requirements, allowing the construction of single-staircase buildings and enabling the development of multiple medium-density residential units on smaller lots. This initiative is projected to unlock thousands of housing units within existing zoning capacities, all while striving for denser housing solutions in the city.
The proposal is set to be discussed at the city council meeting on October 29. It suggests the formation of a task force involving the Departments of Building, Planning, and Fire to develop new rules that would safely permit single-staircase buildings in three to six-story structures. The vision is to establish four- and six-unit residential areas across neighborhoods, putting an end to single-family zoning and offering developers the flexibility to create more housing with higher density.
Architects and residential builders contend that changing the common regulation across most regions, which mandates two staircases for buildings over three stories, is crucial for medium-density projects on smaller plots.
Peskin’s office emphasizes that the state building codes require two stairways in structures over three stories, connected through internal corridors. This unnecessary regulation has led to multifamily development projects that decrease “livability, climate adaptability, family-friendliness, and community orientation” without significantly enhancing resident safety.
“I believe San Francisco can take bold steps by allowing for greater flexibility in the construction of already approved building envelopes, thus unlocking existing zoning capacity,” Peskin stated. “We can foster this ingenuity to meet housing demands without sacrificing protections for renters or affordability. Our aim is to promote a reasonable density that San Francisco is renowned for.”
This policy idea was previously raised by Kathrin Moore, Vice Chair of the Planning Commission, during an informational hearing on state-mandated zoning adjustments on June 4. Moore noted that coupling zoning changes with current building regulations could lead to “stretched, monotonous cubes.” In contrast, modern urban housing in other regions relies on “single-point access [one staircase]” to unleash a “treasure trove of affordable housing built by small-scale developers on discontinuous, small lots.”
Mark Hogan, head of OpenScope Studio, highlighted that the single-staircase building design is a common strategy globally for constructing high-quality buildings on small parcels while increasing building density.
Architect Michael Eliason, affiliated with an architecture and urbanization think tank, remarked that low-rise and mid-rise punctuated access buildings are a primary form of urban housing worldwide, with legal existence in Seattle for over 50 years. Such models can be used to create more affordable, climate-adaptive, and family-friendly housing across urban areas.
