June 16--REPORTING FROM BERKELEY -- Water seeping into the horizontal beams supporting a balcony could have caused dry rot, contributing to a balcony collapse that killed six students in Berkeley, an engineer who examined photos of the damage said Tuesday.
"It appears to be a classic case of dry rot, meaning water intruded into the building [and] rotted the wood" that supported the balcony, said Gene St. Onge, a civil and structural engineer in Oakland. With more than a dozen people on the balcony, "it gave way. It didn't have enough residual strength, and it failed."
St. Onge said photos that he reviewed Tuesday morning, showing the broken wooden beams protruding from the building that once held up the balcony, show what looks like signs of dry rot.
"It appeared to be shredded and darkened and had all the appearance of wood that had been totally compromised by dry rot," he said.
A structural failure without any dry rot would have looked different, St. Onge said.
The balcony itself should have been able to support the weight of 13 or 14 people, he said.
"If you had 14 people, and they were all -- I don't know -- football players, and they were jumping up and down, you would get a fair amount of deflection, depending on how well the railing was tied back," St. Onge said. "But if the [wooden supports] were designed even under minimal standards, it should still have held."
City records show the Library Gardens apartments were proposed as a mixed-use development in 2000 that was ultimately completed in 2007. The building has more than 175 rental units and 3,000 square feet of commercial space.
The property owner is listed as Granite Library Gardens LLP, an investment fund managed by New York-based BlackRock. BlackRock leases the property to Greystar, a Virginia company that owns more than 400,000 residences nationwide, including Library Gardens.
Rent for one- and two-bedroom apartments at Library Gardens range from $2,150 a month to $4,000.
Waterproofing the supports that hold up balconies is extremely important. The wooden horizontal beams that hold them up protrude from the building. If the beams start to rot, the entire balcony can come tumbling down.
"That junction, where the [wooden] members come up beyond the exterior wall, is critically important to waterproof properly," St. Onge said. "It appears as though that something failed there. Either the detailing wasn't adequate, or the construction was not done properly, or something happened that allowed water to intrude.
St. Onge said it's important to inspect apartment balconies.
"We're seeing a lot of structures going back to the '60s and '70s -- they were built properly at the time -- they're starting to fail or failing completely because of age, and they've been neglected and not taken care of," he said. "There have been a number of cases where decks have failed just simply because the owners haven't been paying attention and repairing or replacing them as they should."
City officials declined to comment at an early afternoon news briefing as to what caused the balcony to collapse. They said they are investigating.
City officials said three of the building's other balconies have been red-tagged, meaning people are not allowed on them. They have asked for a complete structural evaluation.
The property management company of the apartment, the Library Gardens Apartment Complex, released a statement Tuesday expressing the firm's condolences over the tragedy.
"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," the statement said. "The safety of our residents is our highest priority and we will be working with an independent structural engineer and local authorities to determine the cause of the accident. We will share more details as we have them."
BlackRock, the current owner, released a statement saying "we are terribly saddened by the tragic accident at Library Gardens and our hearts go out to the victims and their families. The loss of young life is truly heartbreaking and our sincerest condolences go out to all the families and communities affected by today's terrible accident."
BlackRock continued, saying it was in "close contact with the building's management company and an independent structural engineer is being dispatched to conduct a thorough review of the situation."
Panzar reported from Berkeley; Lin and Serna from Los Angeles.
