Is the housing market overvalued by billions due to flood risks?

That house you have might not be worth what you think it is — and a lot of people are in the same boat (and may need one), according to a new study.

Homes in certain areas that are vulnerable to floods are overvalued by $120 billion to $237 billion, Bloomberg reported, citing data from a report published by the Nature Climate Change journal.

The authors of the report got their numbers by determining how much homes are currently selling for and estimating the average yearly losses that homeowners would experience in the event of a flood over the course of 30 years, or the typical length of a mortgage.

Not surprisingly, the biggest differences in value were in coastal areas like Florida, where real estate transactions don’t require the disclosure of the risk of floods, Bloomberg said, citing the report.

“The consequence of this financial risk and how the housing market responds really depend on policy choice on who bears the cost of climate change,” Jesse Gourevitch, of the Environmental Defense Fund and lead author of the report, said, according to Bloomberg. “It is really critical that flood risk is better communicated to property owners.” 

High-value properties accounted for the lion’s share of overstatement, with 11 percent of the properties accounting for 80 percent of the overvaluation, the outlet reported. But the lowest-priced properties stand to lose the greatest portion of their value — up to 10 percent, according to the report.

And a large portion of overvaluation is driven by properties that are not covered by severe flood zones specifically designated by the government, the researchers found.

Much of the problem lies with state and federal governments. States have different requirements as to disclosing flood risks during a sale, while the federal government’s maps that highlight areas prone to floods are outdated or aren’t easily accessible, the outlet said.

In addition, buyers may be prone to risky decision making by underestimating the risk of a flood, Bloomberg reported. The federal government has contributed to those decisions by offering subsidized flood insurance, the outlet said.

It’s not the first study to report billions of dollars of real estate is subject to the effects of climate change.

A report by the New Jersey nonprofit Climate Central said sea levels could fully or partially flood approximately $34 billion worth of real estate on the country’s coasts. That estimate fis projected over the life of a 30-year mortgage.

The nonprofit used tax assessment data from counties across the country, along with tidal level properties boundaries and elevation. It predicted the damage could be much worse by the end of the century, potentially tripling losses in counties adjoined to the sea.