As of June 18, 2013, if you own a residential building of a certain size in San Francisco, you’ll be required to seismically retrofit it. The law specifically applies to wood frame buildings with “soft stories,” which means buildings with three or more stories, or two stories above a basement or underfloor area that has any portion extending above grade. The buildings must contain five or more units to comply with the new rules.
The reason soft story buildings are being singled out is due to the increased level of risk posed by their structural design. During an earthquake, large openings on the ground floor (like garage doors or commercial spaces with large window and door openings) are especially vulnerable. Read more
