Shaking Out Buildings with Soft Stories in Our Neighborhoods

The  U.S. Resiliency Council (USRC)  in collaboration with  Esri , the world leader in GIS mapping, is investigating how many buildings with soft stories may exist in California, as part of its mission to improve community resilience  

Multi-story buildings with weak and/or open wall lines create a “soft-story” often seen in apartment buildings with tuck-under-parking. 

These buildings have proven to perform poorly and collapse in earthquakes. 

“A soft or weak story floor, wood-frame building is a structure where the first story is substantially weaker and more flexible than the stories above due to lack of walls or frames at the first floor. Typically, these buildings contain large open areas for parking or commercial space such as restaurants or convenience stores on the first floor leaving the building highly vulnerable to damage in an earthquake.”

 - City and County of San Francisco Department of Building Inspection  

Economy – much of our workforce lives in older apartment buildings that may contain soft stories. This means impacts to soft story buildings extend well beyond their occupants and will affect businesses and the economies of our communities.

Environment – heavily damaged buildings often have to be quickly disposed of in landfills, where toxic chemicals contaminate the air, soil and water.

Equity – vulnerable populations that live in older, more affordable apartment buildings are often the least likely to be able to quickly find alternative housing after a disaster.

The US Resiliency Council and Esri, the worldwide leader in GIS mapping, examined the demographic characteristics of people living in neighborhoods which have at least one older multi-story apartment building (note: these neighborhoods also have other types of housing).

Neighborhoods with at least older one multi-story apartment building in them contain:

• 56% of the population in the seven county area
• 57% of the households with disability in the seven county area
• 51% of the population age 65+ in the seven county area
• 77% of the households without a vehicle in the seven county area
• 71% of the households below the poverty level in the seven county area
• 69% of the population 65+ who speak Spanish and no English in the seven county area
• 56% of the daytime population in the seven county area
• 64% of the total businesses in the seven county area
• 58% of the total employees in the seven county area

Who is affected by this problem?

• Building residents
• Building owners whose assets may be their largest investment and primary source of income
• Cities and counties whose property tax and employment base is at risk
• Businesses which rely on the workforce living in these buildings
• Lenders and banks which hold the mortgages on many of these properties
• Insurance companies which may face enormous claims after a major earthquake
• State and federal governments which must respond in the aftermath of disasters and provide financial assistance

In Southern California, several cities have adopted ordinances to require soft-story mitigation. There are more than 35,000 locations with older multi-story apartment buildings in these cities, representing over half a million housing units. If 30% of them need retrofitting, that is more than 150,000 units at risk.

There are more than 60,000 locations with older multi-story apartment buildings in cities without ordinances, representing nearly 800,000 units. If 30% of these need retrofitting, that is almost a quarter million units.

Smart tenants are carefully considering earthquake safety when making decisions about where they live or rent. They want to know that their buildings are safe for their families, employees and customers.

Some property owners are taking it upon themselves to voluntarily protect their most valuable assets and income sources, and avoid liability.

Six cities in Southern California have mandated that soft story buildings be seismically retrofitted. In the largest of these, Los Angeles, more than 6,900 buildings, approximately 55% of the total, have already been retrofitted. But that means more than 80,000 older, potentially hazardous buildings are located in cities with no requirement that soft stories be identified or mitigated.

State leaders have discussed laws and incentive programs to encourage retrofit of soft story and other vulnerable buildings. 

The federal government has provided hundreds of millions of dollars for mitigation funding to assist states and localities in implementing various types of hazard mitigation.

Want to learn more? Visit the USRC web site  https://www.usrc.org