New-build homes’ exposure to flooding: a comparative analysis between France and the UK

In many parts of the world the costs of flooding are projected to rise sharply due to climate change and urbanization in flood-prone areas. This study compares the rate of construction in high-risk zones across France and the UK, and discusses the impact of insurance and urban planning policies. In both France and the UK, the housing stock in flood-prone areas keeps growing substantially every year, and new construction in flood risk areas has not shown any sizeable sign of slowing down in recent years. In France, second homes are overrepresented in flood-risk zones, contrasting with the UK. Both countries show higher rates in low-income neighbourhoods, raising concerns about the emergence of socially deprived areas at high risk of flooding that may not have access to insurance, sometimes called “flood ghettos”. While insurance is subsidized in both countries, a key distinction is that new build homes at risk do not benefit from subsidized rates in the UK, whereas they do in France. However, this difference does not appear to substantially deter construction in risky areas in the UK compared to France. These findings highlight challenges in balancing risk reduction, affordability, and sustainable development.