Decision on repairing and renewal of old houses and temporal properties

Improvement of quality of old houses is a critical problem in earthquake risk management. In the past model analysis, it was shown that the incentive to renew a house becomes smaller with the age of owners, and becomes bigger with the history of a house. However, it was not clear if actual owners make decision on renewal of their own houses based on the recognition of degradation risk. Even if owners know that their houses are dangerous, they may not implement any measures. It is also necessary to expand the analysis to incorporate decisions on the repairing that improves safety of a house and costs lower than renewal. In this study, we tried to specify the critical factors that affect owners´ decision on repairing and renewal. We especially focus on two temporal properties, age of an owner and history of a house. First, model analysis on renewal is expanded to apply to more general situations. Second, survey was carried out to examine appropriateness of the models in Yamaguchi City, Japan. Based on the collected data, the parameters for the binary logit model were estimated and it was proved that owners´ age affects their decision and the effects of the history of houses are not clear.