Owners of thousands of wooden apartment buildings at risk of collapse in a major earthquake will begin receiving retrofit orders as early as February, Los Angeles building officials said this week.
This follows the city's adoption of the most sweeping mandatory seismic regulations in the nation. An estimated 15,000 buildings across Los Angeles will be strengthened to better withstand violent shaking.
The law capped decades of efforts to strengthen two types of older buildings that proved deadly in past earthquakes: brittle concrete buildings that dot L.A.'s major boulevards and wood-frame apartment complexes with weak first floors. About 65 people died when these types of buildings collapsed during temblors in 1971 and 1994.
Under the law, property owners will have seven years to strengthen "soft-story" wooden apartments and 25 years for concrete buildings. Soft-story buildings have weak first floors because they often are built over carports and held up with slender columns.
The Los Angeles Department of Building and Safety is finalizing a list of roughly 13,500 soft-story wooden buildings that officials suspect need retrofitting. The list will be ready by early next year, Plan Check Division Chief Colin Kumabe said.
Once the list is finalized, officials will first issue a courtesy letter to every owner explaining the new law and the mandatory retrofit timeline.
Beginning in February, the official order to comply will be mailed on a rolling basis. Owners of the city's largest apartment buildings, with 16 or more units, will receive the first wave of orders. The next wave of notifications will include soft-story buildings that have three or more floors, followed by any remaining buildings on the list.
Owners have one year, from the date they receive the compliance order, to either submit proof that the building doesn't need retrofitting or plans for retrofit or demolition. Within two years of receiving the order, owners must obtain their retrofit permits.
The entire retrofit must be completed within seven years of receiving the order, Kumabe said Wednesday at a technical conference hosted by the Structural Engineers Assn. of Southern California.
Identifying the quake-vulnerable buildings has not been an easy task, officials said.
No city data existed to easily identify which structures are wood-framed and soft-story, engineering bureau chief Ifa Kashefi said in 2014, when the Department of Building and Safety began the survey. Officials focused on structures built before 1978 with at least two stories and at least five units.
The city's housing department provided addresses of 29,226 apartment buildings constructed before 1978. Staffers then used mapping programs to narrow down which apartment buildings needed further field inspection. Officials went on-site to determine whether these remaining buildings should be included in the inventory.
It will take longer for city officials to identify which concrete buildings will be included in the new retrofit regulations, officials said. There are an estimated 1,500 buildings — including landmark buildings in downtown, Hollywood and Westwood — that may require close scrutiny.
Owners will be required to find a way to pay for the retrofits, which can range from $60,000 to $130,000 for wood apartments and millions of dollars for large concrete towers.
City officials are looking for financial aid options — such as tax breaks or permit fee waivers — and are considering a proposal that would allow owners to pass on half the retrofit costs to tenants through rent increases.
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