UC Berkeley

This dissertation investigates earthquake mitigation behavior among a group of rental property owners in Berkeley, California. About 320 owners were affected by a novel local ordinance that sought to address the problem of soft, weak, or open first story wood frame buildings. The law placed notice on the property title and required owners to inform tenants, post warning signs on-site, and hire a structural engineer to evaluate their property. Even though owners were not required to do a seismic upgrade, over 20 percent voluntarily took that costly extra step.

To investigate why some people took precautionary action while others did not, I conducted 43 semi-structured in-depth interviews, including a stratified sample of the affected Berkeley apartment owners (N=37) and some owners who did similar soft-story retrofits prior to the law (N=6). Using a mix of open-ended and survey questions, I developed a rich description of these owners and how the law affected their mitigation investment choices.

My principal finding is that post-law retrofitters were highly motivated by the near-term negative consequences created by the law. The desire to remove stigma (and its perceived economic implications), gain freedom from administrative hassles, and eliminate fear of further regulatory impositions compelled many to act, in some cases more than concern about the actual hazard. Retrofitters and non-retrofitters appear to own similar buildings and otherwise have similar demographic traits and earthquake risk perceptions.

To put this individual behavior into context, I also interviewed 22 key stakeholders involved in developing and implementing the policy and assessed the City of Berkeley's mandatory evaluation approach as a policy strategy. Berkeley's approach successfully influenced enough owners to take voluntary action that the remaining owners now believe that they must either do a retrofit or accept that their property is worth less. The greatest implementation challenge was the development, communication, and consistent application of technical standards for the evaluating engineers to use. Overall, this case illustrates the potential power, as well as some limitations and pitfalls, of using labeling, mandated evaluations, and disclosures to shift social perceptions and behavior regarding risk reduction behaviors.