Los Angeles city building officials have concluded that it would take inspectors more than a year to identify all the apartment buildings in the city that have a certain type of wood frame that is vulnerable to collapse in a major earthquake.
City staffers developed a plan to winnow out these so-called soft story wood-frame buildings among the 29,000 apartment buildings across the city that were built before 1978, Ifa Kashefi, chief of the engineering bureau at the Department of Building and Safety, wrote in a report submitted to a City Council planning committee.
Officials have long known about the risk of soft-story buildings, , particularly after the 1994 Northridge earthquake, when about 200 of these structures were seriously damaged or destroyed, and 16 people died in the Northridge Meadows apartment complex.
Soft-story structures are often built over carports and held up with slender columns, leaving the upper floors to crash into ground-floor apartments during shaking. No city data exist to easily identify which structures are wood-framed and soft-story, Kashefi said.
The city's housing department provided addresses for 29,226 apartment buildings in the city built before 1978, according to Kashefi's report. Staffers would then use mapping programs to narrow down which apartment buildings need further field inspection.
The report estimates that 20% of the 29,226, or about 5,800 buildings, will be soft-story buildings, and an additional 11,690 buildings will need to be inspected on site to determine whether they are soft-story buildings.
Each inspector would be able to examine about 30 buildings per day, according to the report, and the overall inventory would take about one year and several months, a department spokesman said. The report provided a sample checklist of things an inspector would look for in surveying these buildings.
A motion, introduced in July by City Councilman Tom LaBonge, asks building officials to present a proposal for how the city would be able to identify wood-frame soft-story residential buildings with at least two stories and at least five units that were built before 1978.
LaBonge's motion came after San Francisco passed a landmark earthquake safety ordinance this year that requires about 3,000 wooden apartment buildings to be strengthened.
Los Angeles Department of Building and Safety officials are scheduled to present the report to the City Council planning committee Tuesday.
Last Friday, the City Council's public safety committee reviewed another motion by LaBonge and Councilman Mitch Englander. The proposal asks staffers to report on how the city could provide loans or help finance the retrofitting of older concrete buildings and soft story wood-framed buildings.
Englander has said it's unreasonable to simply create an "unfunded mandate" without looking into financial assistance for property owners. A statewide bond program may be the way to help property owners finance the costly retrofitting, LaBonge said.