There’s a growing effort underway to make California communities safer, as cities throughout the state adopt new laws requiring seismic retrofits of buildings proven to be vulnerable to damage in an earthquake.
San Francisco, Berkeley and other Bay Area cities were among the first to mandate earthquake retrofits for wood-framed, soft-story buildings – structures with open parking on the ground floor and apartment units built on the stories above. Los Angeles sparked the trend in Southern California with the nation’s most sweeping seismic retrofit law, adopted in 2015.
Since then, the movement to retrofit buildings at risk of collapse in a large earthquake has taken a major step forward as cities in both Northern and Southern California start planning for retrofit laws of their own. A short list of cities that have adopted or are considering earthquake-retrofit laws includes: San Francisco, Berkeley, Richmond, Fremont, San Jose, Alameda, Santa Clara County, Los Angeles County, Los Angeles, Beverly Hills, Santa Monica and West Hollywood.
The Structural Engineers Association of California estimates there may be as many as 100,000 buildings in Southern California alone facing retrofit mandates as other cities and counties consider adopting retrofit laws like those already enacted in other parts of the state.
Cost benefits of a retrofit
You can’t put a price on the cost of death or injury, and the loss of property resulting from earthquake damage can be much more than what a building is worth. That alone should be enough to prompt owners of at-risk buildings to look into making their structures safer. In many cases, these buildings represent a person’s total assets and retirement plan. Studies show it pays to protect that.
Researchers at Caltech recently performed a general benefit-cost analysis on several types of residential structures including a soft-story apartment building. They found that for every dollar spent on retrofitting, owners could expect to save up to $7 in repairs, and their calculations did not include the possibility of death or injury or the loss of contents within the structures themselves.
Retrofits help to guard against liability, claims of negligence and are beneficial for insurance purposes, too. In fact, many insurance carriers no longer insure soft-story structures built before 1978 against earthquakes. Carriers are becoming more discriminating and will either stop coverage or increase premiums to compensate for the added risk.
Fortunately, many cities have put financing models in place to help owners cover the costs of the retrofits. They want people to do the retrofits and are developing programs that can help.
Why is this happening now?
California is prone to earthquakes. That’s a given. And today, because of advances in seismology and the equipment used to measure and study earthquakes, scientists agree that our state is long overdue for another major tremblor – massive jolts like those experienced in Loma Prieta in 1989 or Northridge in 1994. Both of those quakes killed or injured hundreds of people and caused billions of dollars in property damage.
Geophysicists at NASA’s Jet Propulsion Lab recently determined that there is a 99 percent probability that a major quake will rock California in the next 2 ½ years. It’s not a matter of “if,” but “when.”
As a result, cities throughout the state – particularly those that have experienced severe destruction in the past – are doing their part to protect public safety and to guard against the massive displacement that happens when residents are forced out of their homes due to earthquake damage.