US housing market overvalued by $200 billion due to unpriced climate risks
New economic research reveals hidden risks and overvaluations in real estate market, particularly impacting low-income households.
A examines the potential cost of unrealized flood risk in the American real estate market, finding that flood zone property prices are overvalued by US$121–US$237 billion. Authored by researchers from Environmental Defense Fund, First Street Foundation, Resources for the Future, the Federal Reserve, and several academic institutions, the study also examined how unpriced flood risk throughout the country could impact communities and local governments, finding low-income households particularly vulnerable to home value deflation.
Currently, more than 14.6 million properties in the United States face at least a 1% annual probability of flooding, with expected annual damages to residential properties exceeding US$32 billion. Increasing frequency and severity of flooding under climate change is predicted to increase the number of properties exposed to flooding by 11% and average annual losses by at least 26% by 2050. The increasing cost of flooding under climate change has led to growing concerns that housing markets are mispricing these risks, thus causing a real estate bubble to develop.
Low-income households are at greater risk of losing home equity from price deflation due to factoring in anticipated flood risk. The study found that low-income households stand to lose as much as 10% of their market value.
In general, the study found that highly overvalued properties are concentrated in counties along the coast with no flood risk disclosure laws and where there is less concern about climate change. In particular, properties in Florida are overvalued by more than US$50 billion.
Aside from the impacts to homeowners, municipalities that are heavily reliant on property taxes for revenue are also highly vulnerable to budgetary shortfalls. These municipalities are concentrated in coastal counties, as well as inland areas in northern New England, eastern Tennessee, central Texas, Wisconsin, Idaho and Montana. In these areas, local governments may need to adapt their fiscal structure in order to continue to provide essential public goods and services.
A large portion of overvaluation is driven by properties located outside of the Special Flood Hazard Area (SFHA), identified by the United States Federal Emergency Management Agency as having 1-percent chance of being flooded per year. Properties located outside the SFHA comprised 83% of all properties at risk of flooding and contribute 69% of total overvaluation in dollar terms.
The timing, speed, and extent of devaluation depends on institutional, policy, and regulatory adaptation responses to increasing flood hazards – all of which will impact who bears the financial brunt of climate-related disasters: individual homeowners, taxpayers, or mortgage lenders.
The study is the first-ever assessment of climate risk to property values, using the property-specific, climate-adjusted First Street Foundation flood model. To generate these estimates, the authors evaluated the extent to which property values already account for the costs of flooding. They then compared those price discounts with property prices that fully capture expected damages from flooding over the next 30 years.