The minimum flood elevation requirements for Gulf Coast properties prone to storm surges were “woefully inadequate,” according to a new study, whose sponsors seek federal government intervention to encourage raising the required minimum elevations for building.

“Significantly more Gulf Coast homes and businesses are imperiled by disastrous flooding from storm surge than previously recognized by property owners or policymakers,” according to a statement from the Tampa, Fla.-based Institute for Business & Home Safety.

Its researchers explored property damage caused by Hurricane Ike, which struck the Bolivar Peninsula near Galveston, Texas, Sept. 13, 2008. The institute is an independent, nonprofit applied research and communications organization supported by property insurers and reinsurers.

The study raises questions about the current basis for elevating properties along the Gulf Coast and urges the National Flood Insurance Program (NFIP) to provide greater incentives for building well above the minimum elevations now in place.

More than 50% of the nation’s population lives within 50 miles of the coast, with more than $9 trillion of insured coastal property vulnerable to hurricanes. The NFIP, which is the federal government program that provides flood insurance to homes and businesses, also establishes base flood elevation (BFE) levels for properties.

“Lessons learned from Hurricane Ike, which is the third-costliest hurricane on record, should be used by vulnerable communities from Texas to Maine to effectively reduce property damage in all hurricane-exposed areas,” said IBHS President and CEO Julie Rochman. “Simply put, the study found that many properties are not built high enough to withstand storm surges, tightly enough to prevent water from causing interior damage or strongly enough to prevent damage when high winds strike.”

According to the study’s findings, the BFE requirement for homes on Texas’ Bolivar Peninsula ranged between 13 feet for homes built in the 1970s and 17 feet to 19 feet for homes built beginning in 1983.

All but a handful of properties within the first few rows of houses from the coast, built to even the highest elevation requirements, were washed away during Hurricane Ike, researchers said. By contrast, the study found that 10 homes on the Bolivar Peninsula designed and built under IBHS’s building code-plus new construction program, “Fortified. . .for safer living,” survived the storm, sustaining minor damage. The Fortified homes had outdoor decks at 18 feet that were destroyed, but the homes, which were elevated to 26 feet, survived.

IBHS Senior Vice President of Research and Chief Engineer Dr. Tim Reinhold said most homes in coastal areas are built to or slightly above 100-year base flood elevations. “A 100-year flood means that the level of flood water has a 1% chance of being equaled or exceeded in any single year. However, it is well recognized in the engineering community that coastal homes built to this level have a 26% chance of being flooded or demolished over the life of a 30-year mortgage. This chance increases to about 40% in a 50-year period,” Reinhold said. “All it takes is a breaking wave about 2 feet above the base of a house to knock out the bottom floor or destroy a frame house.”

Reinhold said proper elevation can “significantly reduce” the chances of destruction. Building at the proper elevation “can be relatively inexpensive when building a coastal home,” he said.

“For example, building to a 500-year base flood elevation reduces the chance of storm surge exceeding the base elevation to about 10% in a 50-year period.”