With increasing greenhouse gas emissions and urbanization (the heat island effect), floods have been accounting for a larger part of economic losses globally. The importance of insurance private insurance sector in participating in flood risk management increases accordingly. In this research, we modify the most common and internationally accepted method of assessing building damage due to flooding, i.e., depth–damage curves (DDCs) into probabilistic depth–damage curves (PDDCs). Based on the generated PDDCs, we model the premiums of flood insurance using the Great Tokyo Area as an applied example. Finally, we also quantify the impact of greenhouse gas emission scenarios on individual and aggregate losses and premiums.

The outputs of this project include: Firstly, a high-resolution (50m) flood map contains the spatial distribution of water stages. Secondly, a function between flood depth and probability of damage over certain thresholds, i.e., probabilistic depth–damage curves (PDDCs). Thirdly, premium rating models using PDDCs. And finally, the impact of climate change on insurance premiums.

The results were submitted to APRIA 2022 annual conference, and the further revised version will be presented at IAFICO 2023 annual conference.