Design Strategies for Floor Plans to Improve Evacuation for Elderly Residents During Flooding

This study aims to propose design guidelines for residential floor plans that facilitate evacuation for elderly people during flood events by conducting analyses using flood simulations. In recent years, due to global warming, climate change has become increasingly severe, leading to more frequent occurrences of heavy and localized torrential rainfall in Japan. As governmental flood countermeasures in Japan have struggled to keep pace with the accelerating impacts of climate change, both public authorities and previous research have emphasized the importance of household-level evacuation strategies. Furthermore, there have been reported cases in which elderly individuals were unable to evacuate in time and suffered harm while remaining on the first floor of their homes during flood disasters. Considering Japan's aging society, it is believed that creating homes that allow elderly residents to evacuate easily is one of the most effective household-level disaster mitigation strategies. Therefore, this study focuses on the internal layout of houses and proposes a design method for residential floor plans that enable easier evacuation for elderly people during flooding. In addition, to ensure applicability to existing buildings, this research presents flood protection options involving flood barrier that function as walls. By analyzing both the effectiveness and cost-efficiency of these flood barrier, we propose optimal heights and placements as practical evacuation measures.