Hollywood Hills News
Canyon News spoke with Tom Heaton, the Director of the Cal Tech Earthquake Engineering Research Lab, who defined these high-risk buildings as “old concrete buildings with column frames.” These old concrete, column-framed buildings are susceptible to the sideways movements of an earthquake and therefore need to be retrofitted, or reinforced with bars to protect them from collapse. Heaton said these “non-ductile” or “brittle” buildings “cannot take much damage” and “once the building starts to fail, it all fails.”
Heaton explained that
Luke Zafarani, Chief of the LDBS, told the Canyon News that the agency upgrades their codes every three years but that those codes are only effective from that point on. That means, for example, an industrial building that converted into residential housing prior to the 1976 codes may still have a design that is not strong enough to sustain an earthquake.
According to Zafarani, the LDBS only has the authority to regulate existing buildings “that want to change the use of the building or make changes that would exceed 50 percent of the building’s value.” The LDBS cannot force owners to upgrade the structural integrity of their high-risk buildings and instead offers a voluntary retrofitting program.
The problem is that building retrofits are a very costly, time-consuming venture that many owners either will not or cannot afford. The Los Angeles Times estimated only about 100 buildings have voluntarily elected to retrofit their buildings.
“The problem that is most concerning is the general populous does not know if they are occupying one of the buildings that are at risk because there is no publically available list,” said Heaton. The list created by the Los Angeles Times is only an educated estimate and the
Zafarani explained that it is difficult to create an accurate list because there is no way to know the true construction of a building without having a specialized structural engineer come in and inspect each building. The LDBS has never been commissioned to make such a list, and “if we were mandated to do so we would need to hire more people to do it which could be very expensive,” Zafarani said.
On Tuesday, October 15, Los Angeles Councilmen Tom LaBonge and Bernard Parks issued requests for city agencies to explore the feasibility of creating a list of high-risk buildings, according to media reports.
“If a list was made of these buildings, that step alone would put a lot of pressure on building owners to prove the buildings were not dangerous,” Heaton said.
The last major earthquake in the region was the 1994 Northridge earthquake, nearly twenty years ago. According to Heaton,
Heaton added that no one can predict when or where the next damaging
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