Quake Reveals Widespread Building Defects

By tearing open walls and roofs, the Northridge earthquake has exposed construction defects in a variety of structures, leading some experts to blame poor workmanship and lapses in code enforcement for much of the devastation.

In the three months since the earthquake, building inspectors, engineers and others have found growing evidence of faulty construction--ranging from haphazard nailing to missing grout in a brick wall that collapsed inside a San Fernando Valley fire station.

Each flaw by itself--such as the controversial use of box nails instead of thicker common nails in wood-frame buildings--may seem insignificant, even esoteric.

But experts say the cumulative effect of such errors weakened structural integrity and contributed substantially to the billions of dollars in damage sustained in the magnitude 6.8 quake.

“At least one-third or more” of the quake damage “could be directly attributed to shoddy construction,” said structural engineer Nabih Youssef, who is chairman of Mayor Richard Riordan’s Blue-Ribbon Panel on Seismic Hazard Reduction.

“Damage and major failure would have been prevented if we had better quality control,” Youssef said.

Code enforcement and building performance problems have been noted after earlier disasters, most recently in 1992 after Hurricane Andrew swept through South Florida, where a grand jury blamed poor construction for much of the damage.

In Los Angeles, authorities have yet to determine the exact extent of such lapses. But experts agree that some of the sloppiest work can be found in wood-frame apartment buildings, condominiums and single-family tract homes, which were the subject of a recent USC study on quake-resistant construction.

Funded by the National Science Foundation, the study found that on the average, at least one-third of the seismic safety items checked by researchers were either missing or flawed in 40% of wood-frame structures.

The documented defects included missing “shear wall hold-downs” and anchor bolts, the metal devices designed to hold walls to the foundation and prevent them from pulling out or sliding; improperly sized and placed nails meant to reinforce wood framing, and missing “wall-to-wall straps,” the ties designed to hold each story together and transfer earthquake forces to the foundation.

During the yearlong project published in August, architecture graduate students examined 300 units in about 70 new housing developments, mainly in Southern California. The study also involved a mail survey asking architects and engineers how closely contractors had followed their designs.

“It is alarming that key items to resist seismic load are among those which are most frequently missing or flawed,” wrote architecture professor G. G. Schierle, who supervised the study.

In an interview, Schierle said he and his students returned to many sites, which he would not identify, after the Northridge quake and found “that a lot of damage can be traced back to these faulty constructions.”

David Hoadley, president of the American Construction Inspectors Assn., said that he and other private inspectors who helped Los Angeles building officials after the earthquake noted similar problems.

“I would say overall, as a general rule, the major structural damage occurred because they weren’t constructed properly,” Hoadley said.

Links between alleged construction flaws and earthquake damage are already being drawn in the courts, although experts say they expect more suits to be filed.

In the first-known lawsuits stemming directly from the earthquake, the families of victims of the Northridge Meadows collapse are blaming the deaths on the way the 22-year-old apartment complex was built. Sixteen people were crushed to death or suffocated when the three-story building’s second floor plunged onto the first.

An attorney for six of the victims’ families, Joel Castro, alleged that his experts have identified many building flaws, including nails, joist hangers, metal supporting pipes and other key components that were smaller and weaker than those specified in the plans. In some instances, Castro said, those items were missing.

But expert reviews are still under way and even if building defects are confirmed, it will be difficult to prove that they, rather than the earthquake’s ground motion, caused the collapse, said Robert M. Freedman, an attorney for building owners Shashikant and Renuka Jogani.

It may also be difficult to prove exactly what the apartment complex’s building plans called for, Freedman said, because the official, city-approved set of blueprints has yet to be found. Castro’s set, he contended, is not city-stamped and may not represent the final plans.

Castro, however, said his set of plans came from the apartment complex’s builder and original owner, and are not labeled as preliminary.

Presented with evidence of earthquake damage, a Pasadena Superior Court jury last week awarded nearly $6.35 million to 15 condominium owners whose attorney cited the problems as proof that the five-year-old complex had been poorly built. The 2-year-old case, filed on behalf of the 515 S. Orange Grove Owners Assn., blamed faulty construction for leaky windows, doors and roofs.

During the quake, fire sprinklers were rattled so violently that they sliced through the ceiling, helping to corroborate claims that the condos were not structurally sound, said Lee Barker, the plaintiffs’ attorney.

Attorney Bruce Gridley, who defended condominium builders Victor and Evangeline Illig, said Barker exaggerated the damage and successfully played upon the jurors’ general dread of temblors. “It was the fear, I think, that prompted the jury to do what they did,” said Gridley, who was considering an appeal.

Other attorneys pressing similar suits hope to turn quake damage to their advantage.

Gary W. Verboon, representing the Newhall-Hidden Valley subdivision in the Santa Clarita Valley in a suit over alleged grading deficiencies, said in an interview that the quake caused damage to chimneys, tile roofs and interior walls that led to the discovery of defective construction.

A lawyer for the builder, Urban West Communities, noted that the tract is “not too far” from a spot in the Santa Susana Mountains that scientists say grew 15 inches from the force of the quake. “I certainly think the construction there performed well,” Gregory L. Dillion said.

In Calabasas, condominium owners in the Steeplechase development have alleged for more than two years that flimsy construction was contributing to persistent leaks from roofs, windows and doors. After the quake, city inspectors red-tagged 29 of the 4-year-old project’s 240 units, including four buildings. City building officials later identified missing and improperly installed shear walls, the reinforced panels designed to resist an earthquake.

Such construction problems are commonplace, said attorney Alexander Robertson, who is representing the Steeplechase Homeowners’ Assn. against the builder, Oxford Development. “In mass-produced projects, meaning tract homes and condo projects, the vast majority are fraught with construction defects ranging from the nuisance level to sometimes life-threatening safety issues,” he said.

William D. Morrow, who is representing the builder, did not return phone calls seeking comment.

The quake has exposed construction defects in a variety of structures, although experts say they are most prevalent in wood-frame residential buildings that are often quickly and cheaply built.

In Northridge, Fire Station 70 sustained an estimated $300,000 to $400,000 in quake damage ranging from the collapsed brick wall inside the dormitory to a buckled shear wall that rendered the main garage door inoperable.

Los Angeles officials were particularly concerned by the failure of the brick wall--part of which came down on a firefighter’s bed--because their post-quake inspections revealed that portions lacked any grout.

It was a glaring defect that should have been obvious to inspectors, said City Architect Bill Holland, and one that prompted an investigation of the 14-year-old firehouse for similar oversights.

“Not having the grout there was like having a window frame with no glass in it,” Holland said. The fire station, closed since the quake, is scheduled to reopen this summer.

In Orange County, Anaheim officials are trying to determine whether design or construction flaws are to blame for the collapse of the Sony Jumbotron scoreboard at the city-owned Anaheim Stadium. The multi-ton scoreboard, about 50 miles from the earthquake’s epicenter, collapsed onto hundreds of seats after supporting steel beams snapped in the quake.

Poor workmanship--and inspections--appear to be contributing factors in the cracking of beams and welds in some steel frame buildings, said Youssef, the head of Los Angeles’ seismic safety panel.

“In every joint that was opened, (engineers) found the same imperfection of the weld,” Youssef said. “Inspectors should have detected it and they didn’t. Some of it was there from Day One.”

Code lapses of one type have been so widespread that the Los Angeles City Department of Building and Safety issued an advisory nearly two years ago instructing building designers to compensate for the problem in their calculations.

The department had found that in many buildings, slimmer-shanked box nails were being used instead of stronger common nails specified in plans. Builders had used the weaker nails because they are easier to use in nail guns, saving time.

The city memo in 1992 told architects to assume builders would use the weaker nails, then to over-design the nailing requirements by 20% in their plans.

Department spokesman Nick Delli Quadri said it is difficult for inspectors to tell a box nail from a common nail once it has been set, so officials decided to change the design requirements.

Delli Quadri and other building officials contacted by The Times said their departments are chronically understaffed. Last year, the city of Los Angeles cut 100 building inspectors, or about 20% of its force.

It was not uncommon during the 1980s building boom, he and building officials from other jurisdictions said, for inspectors around the state to cram a dozen or more site visits into an eight-hour day, with time allotted for lunch breaks and writing reports. That means inspectors typically spend no more than 15 or 30 minutes on each project with an increasingly long list of regulations to enforce.

“They are simply spread too thin,” said Andrew Adelman, the top building official for San Jose.

In wood-frame construction, inspectors commonly visit the site at five key points: pouring the foundation, framing, installation of the electrical and plumbing systems, the roof and the final walk-through. But officials said the public should not assume that those visits guarantee a flawless building.

“The bottom line is this,” said Tom Remillard, superintendent of building for Los Angeles County. “We as code enforcement officials rely on the professional expertise of the builders licensed to do the job, and we are there to spot check their work because we don’t have continuous inspection for all types of construction.”

After Hurricane Andrew left $18 billion in insured losses, a Dade County grand jury called for a sweeping overhaul of code enforcement practices, blaming much of the destruction on shoddy construction and local government’s failure to adequately police builders.

Prompted by that costly disaster--as well as the Mexico City earthquake in 1985, the Loma Prieta earthquake in 1989 and South Carolina’s Hurricane Hugo in 1989--the property insurance industry plans to start rating local building departments next year, as it already does with fire departments. A poor grade, to be determined by detailed questionnaires, would result in higher insurance premiums for residents and in turn, insurers hope, put pressure on local officials to improve code enforcement.

“The program will evaluate whether the code that has been adopted is in fact being enforced,” said Eugene Lecomte, president of the Boston-based Insurance Institute for Property Loss Reduction.

Meanwhile, Youssef is proposing creation of a specialized team of city inspectors that would receive training in seismic-resistant construction to better understand the importance of key connections and how an earthquake’s forces travel through a building.

And city building officials and state Sen. Tom Hayden (D-Santa Monica) are advancing similar proposals that would compel engineers and architects to visit construction sites to ensure their plans are carried out.

Experts widely agree that many errors occur in the field because contractors often need help interpreting building plans, but owners are reluctant to pay for their designers to be available on the site. The presence of the designer would also add another level of oversight, USC architect Schierle suggested in his study.

“To ignore the problems with construction quality control and blame future losses as ‘acts of God,’ despite the fact that we have the means to mitigate them, is irresponsible,” he wrote.