Do You Live or Work in One? City Identifies 472 "Soft Story" Buildings Susceptible to Earthquake Collapse

Owners will likely be required to retrofit their buildings, which are primarily office and apartment buildings

Published : Tuesday, May 29, 2018 | 5:39 AM

Pasadena Now has obtained a list of the addresses of nearly 500 Pasadena buildings which may be susceptible to collapse in the City’s next major earthquake.

The list’s release comes on the heels of the Pasadena City Council’s recent move to increase the pace to develop a new ordinance requiring the buildings’ owners to upgrade them.

Mayor Terry Tornek told the City Council meeting two weeks ago that “we need to saddle up and get this done. This needs to move more quickly, especially the outreach at the front end.”

“The ordinance needs to be done in less than a year,” Tornek said.

Councilmember Steve Madison agreed with Tornek and said that “soft stories are only one part of the [retrofit] puzzle. We need to move with all due speed.”


To check the list of addresses, click here


The yet-to-be-written ordinance would likely require the owners of 472 definite “soft story” apartment and office buildings, and possibly another 28 “undetermined” structures in Pasadena to begin to retrofit their buildings to prevent collapse during an earthquake.

“The ordinance has not been drafted, but will likely include provisions requiring property owners to upgrade their buildings with considerations given to timing, number of units within a structure, and overall safety of building,” Pasadena Planning Director David Reyes said.

Addressing the costs of retrofitting each of the buildings, Reyes added, “The cost is determined on case-by-case basis, based on the type of building’s design. The cost will be determined by the contractor and engineer hired by the owner.”

“Construction varies,” said Eran Itzhaki, co-owner and general manager of Titan Contracting Services, asked about the average time needed for such retrofits. “It can take a month or three months depending on the scope of work involved in each project.”

Asked about the costs, Itzhaki said “Simply creating the engineering plans for contractors for such projects can range from $5,000 to $12,000 per building.

Itzhaki also noted that a complete “moment frame” (which stops a building from moving from side to side in a tremor) can cost $30,000-$50,000, and that the “rule of thumb” is that one such frame is required for every four parking spaces in a building.

“Soft story” buildings are wood-frame buildings with more than one story that typically have extensive ground story windows, garage doors, or open-air spaces (such as “tuck under” parking common in apartment buildings) with few or no enclosing walls.

“They are a particularly dangerous type of building,” Caltech Seismological Laboratory Research Associate and former U.S. Geological Survey Science Advisor for Risk Reduction Dr. Lucy Jones said previously.

Jones noted that many of the buildings which would fall under the ordinance are affordable housing structures, similar to “the apartment building that collapsed in the 1994 Northridge earthquake, killing 17 people.”

“We’ve known their problems,” added Jones, “and we haven’t allowed them to be built that way since the 1978 building code changed the requirements, but of course, lots of the buildings in Southern California were built before then, and this is a particularly common type of structure for apartment buildings.”

In recent years, Los Angeles, Santa Monica, and West Hollywood have similarly required retrofits to potentially vulnerable buildings.

The City has contracted with Degenkolb Engineers to develop the multifamily wood building soft story ordinance and to form an Advisory Group composed of stakeholders, such city technical staff, local structural engineers and architects, Caltech members, local developers, local real estate professionals, and local housing associations.

The Advisory Group will help recommendations to City staff on non-technical items such as timeframes and prioritization.

As part of developing the ordinance, the City will also create a Technical Committee of experienced members of the Structural Engineers Association of Southern California (SEAOSC) to review the technical portions of the ordinance and provide comments to staff and hold two community outreach meetings to present the ordinance to the public and receive comments.

The City Planning Department is anticipating drafting the ordinance for review this summer, and now hopes to have the ordinance adopted within one year, per Mayor Tornek’s recommendation.

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