SAN FRANCISCO (KCBS) – Owners of so-called ‘soft-story’ building, prone to being severly damaged in an earthquake, can expect to be hearing from the city of San Francisco over the next few months.

In April, San Francisco formally adopted a strict retrofit law; it applies to an estimated 3,000 buildings deemed prone to collapse in a major earthquake. More specifically, the subject properties were built before 1978, stand at least three stories high, and are comprised of five or more dwelling units.

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Such structures are referred to as soft-story buildings. They are made of wood framing and generally include a garage, large windows or similar ground floor openings.

The concern is that, in an earthquake, the bottom floor of a soft story building won’t withstand the shaking, allowing the building to collapse or “pancake.”

After Mayor Ed Lee signed the legislation, city officials advised that they would begin sending notices to property owners, warning that their property may be subject to the law. If that is the case, property owners would be afforded one year to hire an architect or engineer to complete an inspection to determine whether the building requires retrofit.

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It’s estimated that the average cost of such retrofit work will vary between $60,000 and $200,000.

Low-income housing advocates have expressed concern that landlords will impose rent increases to cover such costs. Legislation was pending in the Board of Supervisors that would allow for some rent hike exemptions or other protection for low-income and fixed-income residents.

Ultimately, experts warn that the retrofit work is essential.

“If we had an event like we expect on the Hayward fault or something similar to the magnitude of the 1906 earthquake, you would see significant collapse of these buildings and significant loss of life,” said Patrick Otellini, Director of Earthquake Safety for the City and County of San Francisco.

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