Most people know insurance isn't going to help pay for flood damage to their house, a poll released today by found, but not many homeowners have done anything about it.

More than 80% of those surveyed understand the flooding limitations of homeowner's insurance policies, the poll found. But Bankrate cited data from the Insurance Information Institute showing that only 13% of homeowners have obtained flood insurance. That's despite the Federal Emergency Management Agency determining that flooding is the top natural hazard in the United States.

"This is a classic 'Do as I say, not as I do' situation," said Doug Whiteman, a Bankrate insurance analyst. "The vast majority of Americans know the key facts about flood insurance, but they haven’t taken the necessary steps to protect their homes."

Properties are typically classified by FEMA as either at a high risk of flood or at low to moderate risk, according to Bankrate, which found that only about half of those surveyed knew which category they were in. The National Flood Insurance Program reports that about a quarter of all claims come from the lower risk zones. Floods can be caused not just from overflowing rivers, but also from melting snow or excessive rain.

After finding out what their risk level is, Whiteman said, homeowners should check to see what their current policies cover (and don't cover), and look into obtaining flood insurance if they don't already have it. Such coverage can be relatively inexpensive, he said.

"The average flood insurance policy costs about $50 per month, so for roughly the cost of dinner and a movie, consumers can protect themselves against disaster," Whiteman said.

Federally backed flood insurance -- which can be purchased from certain insurance agents -- covers damage to the dwelling and contents. However, the amount of coverage is limited and homeowners with higher-value properties (more than $250,000) or high-priced contents (more than $100,000) should also look into obtaining supplemental coverage.

Bankrate noted insurance industry statistics that showed a lower percentage of homeowners have flood insurance now (13%) than did in 2008 (17%), and that while Florida residents took out the most flood policies, states in the Midwest had suffered the most flood damage in recent years.

You can find out more about flood insurance and get the flood-risk rating for your property and an estimate of rates -- whether you're an owner or renter -- at the National Flood Insurance website. Getting flood insurance shouldn't be a last-minute decision when waters start to rise, since policies typically begin after a 30-day waiting period.

Another issue to consider is what would happen if flooding made your home uninhabitable -- something flood insurance through the federal program does not cover (although privately written flood insurance might).

Homeowner's insurance usually covers some housing costs when you're forced to relocate, but not when the reason is flooding. So if your house is damaged due to flooding, you're dependent on whether FEMA steps in or if reasons other than flooding could trigger your homeowner's coverage, such as a tree falling on the house or a mandatory evacuation.

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