Résumé

As climate risk intensifies, governments increasingly subsidize home insurance against natural hazards. While this policy lowers premiums for high-risk households and maintains broad insurance coverage, it may also distort location choices and raise exposure in hazardous areas. In this paper, I study this trade-off in the context of the French coastal real estate market. I document that home insurance premiums are effectively uncorrelated with environmental risk, creating weak price signals for households about the cost of exposure. Consistent with this muted incentive, cross-sectional regressions and staggered difference-in-differences around the official disclosure of environmental risk maps reveal no price penalty for exposure. To assess the broader consequences for household sorting, construction patterns, and aggregate value-at-risk, I develop a spatial equilibrium model of housing demand and supply featuring disaster risk, land-use regulation, and flat insurance pricing. Counterfactual simulations examine how introducing risk-based premiums would affect housing-market outcomes, welfare, and the long-term sustainability of the French system.

Informations pratiques