San Francisco considers allowing six-story walkups with one stairway

A six-story walk-up with only one stairway? No such development is allowed in San Francisco, but that could change as a way to encourage housing.

Supervisor Aaron Peskin has asked the city’s Fire Marshal, Department of Building Inspection and Planning Department to look at allowing apartment buildings of up to six stories to be built around a single staircase, the San Francisco Chronicle reported.

The change in the city building code might spur developers to build more housing, some say. Peskin’s resolution, supported by Mayor London Breed, heads to the full Board of Supervisors next week.

Peskin is one of several challengers to Breed’s hopes of re-election in next month’s election.

San Francisco, like many cities, requires building higher than three stories to have two stairwells that can be used as fire exits.

The code requirement forces architects to design buildings around a double-loaded corridor, or long central hallways with apartments on either side, similar to a hotel.

But corridor design is inefficient and costly, according to Kathrin Moore, vice president of the San Francisco Planning Commission.

She said a fire exit on a centrally located stair, as practiced in Europe, is a far more manageable and “economically defensible” design.

“Aside from creating better architecture,” Moore told the Chronicle, “it has cost savings and it’s safe.”

While common practice in European cities, Seattle has led the charge on single-stair reform in the U.S. Decades ago, the city tweaked its building code to allow for single-stair buildings up to six stories.

Peskin’s resolution urges San Francisco to consider single stairs.

A year ago this month, state lawmakers passed Assembly Bill 835, which directed the State Fire Marshal to research and develop standards for single-stairway multifamily buildings.

But Peskin said San Francisco could make the changes sooner.

“Single-stairway building code equivalencies are something that San Francisco can adopt, without any necessary change to state law, and can unlock tens of thousands of new residential units from density purgatory,” he told the Chronicle.

“This is another creative way to sensibly grow our city.”

— Dana Bartholomew