Los Angeles is considered one of the most earthquake-prone urban areas in the nation. According to the United States Geological Survey, there’s a 60 percent chance an earthquake measuring in at magnitude 6.7 or higher will strike the Los Angeles area in the next 30 years; there’s also a nearly one-in-three chance that an earthquake will measure in at 7.5 on the Richter scale.

Thousands of homes and apartment buildings are at risk of major damage in Los Angeles, though new rules requiring seismic retrofits for some of the most vulnerable structures should help mitigate the destruction.

Soft-Story Apartments

If you look around a typical Los Angeles neighborhood, there’s no doubt you will find a soft-story building. Soft-Story buildings are easy to identify because they feature tuck under parking (this is parking that is below raised parts of the structure), a popular design for apartment buildings. This type of apartment building design is prone to structural failure and collapse during earthquakes if not built to modern building code. Such buildings collapsed in the 1989 Loma Prieta earthquake and the 1994 Northridge earthquake, including one apartment building where 16 people died.

Los Angeles inspectors have developed a list of 13,500 soft-story buildings that will probably need seismic strengthening. These apartments, which feature flimsy first floors that often serve as parking spaces, became popular in Los Angeles after World War II.

Why Do They Collapse?

The soft-story design was easy to build in the 1960’s, but they do not comply with newer, more stringent seismic code. The first story is too weak to support the entire structure during an earthquake.

During an earthquake cracks can form on the beams; poorly reinforced columns lose cement and then collapse under disproportionate lateral stress. Any soft-story apartment building in Los Angeles, West Los Angeles, and the San Fernando Valley that was built prior to 1980 is considered at risk of collapse during an earthquake.

Fortunately, there is technology to protect your apartment building, office or schools. This new technology enables a building to efficiently ride out an earthquake and minimize damage.

How Do You Retrofit a Soft-Story?

Today, there are sophisticated instruments to detect the volatility of earthquakes all over the country, especially in seismic regions. Computers can now accurately predict how susceptible a structure is. With each major earthquake, new fault lines and at-risk areas are discovered.

Optimum Seismic can help you with your soft-story retrofit. We are a California Licensed Contractor and our team of engineers and designers are ready to work for you. We are committed to making the soft story retrofit process as quick and painless as possible. If time is of the essence and you want to complete the soft story retrofit quickly, we can help.

Earthquake Building Codes

The State of California has a host of earthquake building codes, but there are also local earthquake building codes that impact buildings in different cities. If your buildings are in one (or more) of the following locations, double check those local earthquake building codes. If your location isn’t listed here, don’t assume there aren’t building codes you need to follow there. Make sure to schedule a consultation with one of our structural engineers to assist you in finding out which building codes impact your business.

Many cities in California are taking the initiative to pass local legislation requiring the assessment and retrofitting of specific structure types that have been demonstrated to be at risk during seismic events. These mandates were made because of less than ideal performance of specific classes of structures during past seismic events, for example, the 1989 Loma Prieta and the 1994 Northridge Earthquakes.

Los Angeles

Los Angeles building owners should check the Los Angeles earthquake retrofitting website for details on building codes. Los Angeles also has a searchable map, as well as a browser-based address search option that enables you to type in your address and find out if your property is on the list of buildings that need to be brought up to code.


To address the pubic safety issues presented by earthquakes, the City of Pasadena has adopted an ordinance requiring seismic retrofit of older, wood soft-story apartment buildings citywide that were built under building code standards enacted prior to January 1, 1978.

San Francisco

The San Francisco Department of Building Inspection is in charge of evaluating which properties need seismic retrofitting work done, specifically for soft-story buildings. Make sure to check their searchable map for any buildings that you own that may need to be brought up to earthquake safety codes.

Santa Monica

Santa Monica adopted new earthquake building codes in 2017, so many older buildings there still need to be brought up to “earthquake safe building” standards. The city has a seismic retrofit program to help building owners, and you can view this searchable map, as well as the city’s open data list that pinpoints property addresses that need to have seismic retrofitting done.

West Hollywood

West Hollywood also updated its earthquake safe buildings ordinances in 2017, and outlined what buildings fall under their seismic retrofit program. Their searchable database allows you to input your buildings’ addresses, and it will bring up information regarding what work needs to be done to bring the building up to earthquake-safe standards.

Want to Learn More?

The California Geological Survey has created an interactive, statewide map of California earthquake zones that enables business and building owners to drill down to their exact location to find out more about their earthquake risks. Gathering this important information is the first step in the process to making your building safer in the event of an earthquake.

Build Smarter, Better Structures with Optimum Seismic

If you are concerned about your apartment building or commercial property you can contact Optimum Seismic to learn what steps you can take to safeguard your building in the event of an earthquake. We have the ability to make smarter, better performing buildings now. Why wait for disaster?

Optimum Seismic has 36 years of experience providing earthquake retrofitting services for multi-family apartment owners, as well as industrial, commercial, and office properties throughout California. Schedule a seismic retrofitting consultation for your buildings today or call us at (833) 978-7664 to speak with one of our experts.