Deadly Berkeley Balcony Collapse Linked To Water-Damaged Wooden Beams

BERKELEY (CBS SF) -- The Berkeley mayor says the city should revisit its building codes after a balcony in an apartment building collapsed, killing six people and injuring seven more.

Mayor Tom Bates said the early investigation pointed to moisture-damaged wood as the prime cause of the tragedy. "I'm not an expert, but we understand in looking at it that probably more than likely, water got into the wood and caused some kind of dry rot that occurred in the wood," said Bates. "But that will be substantiated later by people who actually know what they're talking about."

Bates said the speculation is the balcony was improperly caulked and sealed when it was built.

Later, Bates clarified his statement to reporters about the possible cause. "It was speculation on my part about possible water damage to the wood supports for the balcony," said Bates. "That is not an official conclusion. I am not a structural engineer and am not qualified to make a judgment. We are still awaiting the outcome of the thorough investigation that is underway."

Bates said perhaps the city should revisit its building codes to require a material more substantial than wood for balcony support, adding the building was planned and approved that way by the city and is perfectly within the guidelines.

The crowded fifth-floor balcony broke off an apartment building during a 21st-birthday party held by visiting Irish college students, spilling 13 people 50 feet onto the pavement below. In addition to the six killed, seven were seriously hurt.

Local structural engineer Enjin Yagmur agrees with the assessment of water damage.

"The balcony should be able to handle this kind of load," Yagmur said. "I believe there was damage after construction and from the photos I observed some water damage."

Berkeley officials said the building code at the time of construction in 2007 required the balcony to hold at least 60 pounds per square foot. That requirement has since been raised to 100 pounds.

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City spokesman Matthai Chakko said officials have not measured the balcony to find out how big it was and how much weight it was built to bear based on the older standard. Chakko also said there is no city requirement to post a weight restriction for balconies in apartments.

Grace Kang, a structural engineer and spokeswoman for Pacific Earthquake Engineering Research Center at Berkeley, said the balcony's dimensions looked to her to be 4 by 6 feet, or 24 square feet.

That would mean the balcony should hold at least 1,440 pounds, which likely would have been exceeded by 13 adults.

"They were packed like sardines, and then they were moving," she said. When people are moving, it "may further exacerbate" the strain.

Burlingame lawyer Niall McCarthy, who has represented victims in five Bay Area balcony collapses, said these types of incidents are "100 percent avoidable."

"Due to the complete inadequacy of ... inspections around the Bay Area, you literally have ticking time bombs," McCarthy said. "Balcony maintenance is a life-and-death issue. If your plumbing goes out, you have a headache and water in your building. If you don't maintain a balcony, somebody dies."

Employees from Greystar, the building's management company, were at the scene Wednesday morning. In a statement, a spokesperson said:

"Our hearts go out to the families and friends of the deceased and those injured in this tragic accident.   As the property management company, we have taken precautionary steps to limit access to other balconies at the apartment complex as law enforcement completes its investigation."

Building resident Sari Kosdon said she's scared a balcony collapse occurred in a building only 10 years old.

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"I'm living in a structure that may be unsafe," she said.

Two other balconies on the building have been red-tagged bringing the total to four.

Berkeley police received a noise complaint about the loud party on that doomed balcony, but were tied up at a shooting and did not immediately respond.

A makeshift memorial at the scene continues to grow as more is learned about the young Irish nationals. Most of the victims' families arrived in California from Ireland on Wednesday.

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