Mandatory Tests of Steel-Frame Buildings Urged

Responding to widespread reports that steel building frames cracked during the Northridge earthquake, city officials are pushing a costly proposal to require the inspection of at least 400 steel-frame office buildings throughout the San Fernando Valley and the Westside.

The proposal--the first step in the city’s strategy for addressing the most startling discovery of the Jan. 17 quake--is sparking dissent among building owners.

But it is expected to draw support from safety-minded tenants of the buildings, which include many of Los Angeles’ high-rises.

Councilman Hal Bernson, who also serves on the state Seismic Safety Commission, agreed Friday to take the building officials’ proposal to the City Council next week.

Under the proposal, building owners in the Valley and along the San Diego Freeway corridor from the Valley to Santa Monica will be required to inspect their buildings within three months of notification by the city.

Such inspections by structural engineers and ultrasonic testing firms involve tearing into walls and stripping steel columns of fireproofing to examine the frames for cracks.

Owners would have one year from the time they are notified to fix the problems.

The city is also considering whether to require owners of many of the remaining 600 steel-frame buildings, including those in Hollywood and Century City, to conduct similar inspections.

Depending on the inspection results, Bernson and building officials said, they may seek a citywide ordinance to retrofit, or shore up, all 1,000 steel-frame buildings.

Karl Deppe, assistant chief of the Building and Safety Department’s resource management bureau, said a citywide retrofitting program, though costly and time consuming, is likely. He said steel buildings constructed after 1970 would probably be affected by such a program.

Bernson said: “Building owners don’t want to spend money. . . . Some of them don’t have the money. But we have to ensure people’s safety.�

Tom Sabol, an engineer who serves on the city’s building and safety panel studying the problem with steel-frame buildings, said: “I would recommend retrofitting all (of them). None of these structures collapsed. Nevertheless, in a more significant earthquake, it may overwhelm the reserve strength of these structures.�

Steel-framed mid- and high-rise buildings are designed to bend with the enormous forces of an earthquake without breaking and were considered among the safest to ride out an earthquake.

Experts said cracks had not been detected in steel-frame office buildings--which made up half of all buildings constructed last year in Los Angeles--until the Northridge temblor.

Engineers have emphasized that no steel-frame buildings came close to collapsing. But in recent weeks, some earthquake experts have noted that in some buildings up to 90% of the welds that hold vertical columns and horizontal beams together had broken.

“This is a very serious problem,� Deppe said. “It’s very important that these connections be repaired.�

The proposal from building officials said that inspections are needed because “damage to these steel-frame connections . . . could expose occupants of these buildings to a potential life-safety risk in a future earthquake.�

In buildings with six floors or less, the first story’s steel connections would be checked for cracks. In taller buildings, stories in the middle third of the building would be inspected.

If any cracks are found in these preliminary inspections, all of the building’s connections would have to be checked, said Richard Holguin, assistant chief of the city’s building bureau.

Building owners would have to file an inspection report with the city’s building and safety department.

For a six-story building with 120 joints, or connections, a preliminary inspection would cost about $4,000, and a full-fledged inspection of all the joints would cost $12,000, Bernson said.

Insurance companies typically do not cover the cost of these inspections, said Kathy Crook, with Johnson & Higgins, an insurance brokerage firm.

Geoffrey Ely, executive director of the Los Angeles Building Owners and Managers Assn., said his members would support reasonable inspections. He said requiring building owners to have engineers visually examine joints for possible damage is reasonable, but having them ultrasonically test every joint is not.

Ely said the timetable for the repairs is too short.

“It’s obvious that if you have major expenses and high vacancies, this poses major problems for some building owners,� said Ely, adding that these costs were likely to be passed on to tenants.

City officials say cracks in steel frames have been found in at least 60 buildings up to 23 stories high.

Santa Monica officials say they will follow Los Angeles’ lead. The Building and Safety Commission will propose an ordinance requiring inspections of the 20 or more steel-frame buildings three stories or taller, said building officer William Rome.

The California Seismic Safety Commission issued a public advisory about steel-frame office buildings last month, urging that owners who observed even cosmetic damage to their buildings have them inspected for cracks.

Los Angeles officials have already required that all new steel-frame buildings use more rigorous welding procedures.