Ralph Grippo, the Torrance director of building and safety, went to the Bay Area after the Oct. 17 earthquake and inspected 20 homes in Santa Cruz County.
Working as an emergency inspector, Grippo tagged more than half as unsafe to occupy, because "they had just kicked off the foundations."
He came home worried about older wood frame houses in downtown Torrance.
But there is no law in Torrance, or elsewhere in Los Angeles County, that requires seismic upgrading or even seismic evaluations of single-family homes.
At least 22 cities in the county, such as Torrance and the city of Los Angeles, have earthquake safety ordinances. But they address pre-1934 unreinforced masonry buildings, which are often brick-faced structures concentrated in older communities, such as downtown Los Angeles and Hollywood.
Unreinforced buildings have gotten the lion's share of public attention. But officials such as Grippo and other safety experts say unreinforced masonry is not the only type of building to worry about.
Single-family homes, old or not, that are not properly bolted to their foundations are at risk, they say. Other structures described as potentially hazardous are: buildings with first-story garages or carports, a style not uncommon in apartment and office buildings; buildings made of pre-cast concrete, commonly found in warehouses or industrial parks; concrete buildings constructed in the 1960s and earlier that could pancake the same way the Nimitz Freeway did in Oakland.
"We still have many hazards remaining," said Fred Turner, structural engineer with the State Seismic Safety Commission in Sacramento. "Professional engineers have known this for years. Now the public is beginning to realize it."
Parts of many heavily used public buildings are constructed with unreinforced masonry and remain to be upgraded, including city halls in Los Angeles, Pasadena, Culver City and Claremont, the Los Angeles County Hall of Justice and the County Museum of Natural History.
According to a state Department of Conservation estimate, 34% of the hospital beds in Los Angeles and Orange counties will be lost in the event of a major earthquake on the Newport Inglewood Fault Zone. State laws do not require hospitals built before 1972 to be seismically upgraded unless they undergo voluntary renovations.
There is an unknown number of buildings constructed after the Long Beach earthquake in 1933--which led to the first state and local laws requiring seismic resistance designs--that may not be safe by today's standards. No inventory has been taken of them.
"There's a large inventory of buildings which were built under codes in the 1930s or 1940s that were less strong than current ones," said Pat Campbell, president of the Structural Engineers Assn. of California. "Those buildings may have structural problems in a major quake."
The Uniform Building Code, a set of structural requirements for building construction and safety, did not require until 1952 that single family homes be bolted to their foundations.
There are no retroactive state laws requiring homes built before then to have such bolting done, officials say. Assemblyman Dominic L. Cortese (D-San Jose) introduced a bill two years ago requiring this, but it died in the face of realtor opposition, according to a spokeswoman at his office.
Other than unreinforced masonry structures, the only buildings covered by retroactive laws are public schools. The state, not local governments, has regulated school safety requirements since the Field Act was adopted after the 1933 quake. Even though that only covered new construction, a later law called the Garrison Act required that any unreinforced masonry schools had to be upgraded or abandoned.
Hospital construction standards are also controlled by the state under the Hospital Act of 1972. But it did not have retroactive provisions, and a survey done by the Office of Statewide Health Planning and Development showed that "80% of the buildings don't meet the standards," spokesman Derek Pogson said.
But David Langness, vice president of the Hospital Council of Southern California, said he believes most of the 164 general acute care hospitals in Los Angeles County meet seismic safety standards.
The safety of a single-family house might simply depend on the quality of construction, said Michael Krakower, a South Pasadena structural engineer. Most houses built before the 1950s were either not anchored or inadequately anchored, with bolts set too far apart. "Those kinds of things were not common unless you had a knowledgeable or creative builder," Krakower said.