Two years ago, San Francisco officials started identifying all apartment buildings in the city with a specific, earthquake-vulnerable design flaw.
Their latest count shows about 5,000 need seismic strengthening.
Owners of all multi-unit residential buildings were required to have the buildings professionally inspected by last September under the city’s mandatory retrofit program if they appeared to possess a “soft story,” a weak first floor that can collapse beneath the rest of the building during an earthquake.
When the count began, city officials estimated there were 3,000 vulnerable buildings housing 58,000 San Francisco residents, as we reported in our cover story from winter 2012-2013. Some of the rest of the city’s 800,000 residents live in newer apartment and condo buildings or ones that have recently been retrofitted.
Most city residents live in one- and two-family houses, which aren’t covered by the program, though many of those buildings have soft stories and could be vulnerable to collapse in an earthquake.
Each of the identified buildings has a retrofit deadline that depends on how many residents it houses, whether it also contains businesses on the first floors, and other considerations. Only 13 buildings must be retrofitted by the first deadline, September of 2017. Most others have fewer than 15 residential units — and no businesses on their first floors — so they qualify for a 2019 deadline. All of the buildings must be retrofitted by 2020.
The city has yet to give an updated estimate of how many residents are affected.