Homeowners who suffered damage from Hurricane Irene got some good news from the state that their claims won’t be reduced by the hurricane deductibles that are in some homeowners’ insurance policies.

But others discovered, as so many have after a storm surge, that coverage for major flood damage requires a separate policy from the federal government.

The state Department of Banking and Insurance announced that hurricane deductibles will not apply to insurance for homeowners who suffered property damage in connection with Hurricane Irene.

Hurricane deductibles are out-of-pocket costs that are included in some homeowners’ insurance policies, particularly in coastal areas.

They put more financial responsibility on the shoulders of homeowners by basing the deductibles on a percent of the insured value of the house if sustained winds reach 74 mph or faster.

Because these deductibles are typically 1 percent to 5 percent of the insured value of the house, the difference could be thousands of dollars more in costs for homeowners.

On Monday night, Thomas Considine, commissioner of the banking and insurance department, issued a bulletin to insurers saying the deductibles do not apply because the sustained winds were not strong enough.

“This was an important decision,” said Patrick Breslin, spokesman for the New Jersey Manufacturers Insurance Co., which insures 222,000 homes. Of those, 9,200 have hurricane deductibles, the company said.

New Jersey is one of 18 coastal states that allow hurricane deductibles, which have rarely been an issue due to the rarity of hurricanes striking the state. Mandatory hurricane deductibles are allowed in 92 coastal ZIP codes in New Jersey.

Such relief won’t be coming for many people who lacked federal flood insurance and had flood damage from Irene.

Whether water damage is covered by a homeowner’s policy depends on how it came about. Standard homeowners policies cover structural and water damage when wind or a falling tree knocks a hole in a roof, or breaks a window, allowing rain to fall inside. But there’s generally no coverage for the home itself, or for personal belongings, when damage results from rising water. That includes water that seeps up from saturated ground through a basement floor, and homes near beaches flooded by storm surges.

When Irene hit the East Coast over the weekend, flood damage was greater than wind damage in most regions. Inland areas were among those hardest hit by rains that produced flash floods.

Yet many homeowners will be stuck paying all repair costs out-of-pocket, after claims adjusters conclude upon inspection that flooding was to blame, and therefore damages aren’t covered.

That experience could cause many to reconsider whether to buy a separate flood insurance policy in time for the next storm.

“Nothing sells flood insurance like a flood,” said Robert Hartwig, president of the industry’s Insurance Information Institute. “It’s always the case that we see a surge in flood insurance sales in the wake of a flood.”

A poll this year by the institute found that just 14 percent of homeowners nationally had a flood insurance policy. The lowest coverage was in a region hit by Irene: the Northeast, with 5 percent. The highest coverage rate was in the South, with 19 percent.

The Federal Emergency Management Agency said most of New Jersey’s 230,000 property owners with flood insurance are in the southern coastal counties. Cape May and Ocean counties each have slightly more than 50,000 properties insured, and Atlantic slightly more than 30,000.

Coverage remains low despite court cases consistently upholding the industry’s denial of homeowners insurance claims involving damage from flooding, rather than wind, Hartwig said. A series of lawsuits followed in the wake of Hurricane Katrina, which hit the Gulf Coast in 2005.

Nearly all flood coverage is purchased through the government’s National Flood Insurance Program. Homeowners, renters and business owners in about 21,000 communities nationwide are eligible to purchase federally backed flood policies, typically through private insurers that market the coverage. Information is available at www.FloodSmart.gov.

The average flood policy costs about $600 a year, but can start at about $129 in low-risk areas, according to FEMA, which administers the insurance program. The average paid claim over the last five years was nearly $34,000.

The Associated Press contributed to this report.

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