Newer homes and commercial buildings constructed to modern standards fared better in Hurricane Ike than older structures, but roof design still needs improvement, according to an insurance-backed research institute.

The Tampa, Fla.-based Institute for Business & Home Safety (IBHS) said the results from a two-day survey of property damage in Galveston, Houston and the surrounding Texas area indicates that more attention needs to be paid to building standards for roofs.

“The damage we have seen from Hurricane Ike drives home the need to establish clear definitions and standards for secondary water protection to achieve the kind of performance we need to keep water out of homes when these storms occur,” Tim Reinhold, IBHS chief engineer, said in a statement.

The survey reinforces that more attention needs to be paid to roofing design, he said, adding that it was the number-one point of concern in this storm.

Secondary water protection is the moisture barrier between the roof deck and roof covering, IBHS noted.

Hurricane Ike struck the Texas Gulf Coast on Saturday as a very strong Category 2 storm on the Saffir-Simpson scale. It destroyed many homes in Galveston and swept into Houston, where it damaged a number of commercial buildings as well, leaving area residents without electricity for what could be weeks.

According to the U.S. Department of Energy, as of 6 a.m. today, an estimated 3.09 million customers remain without electricity in seven states. Another 3,864 are without power in New York, Illinois, West Virginia and Missouri The most are in Texas, numbering more than 1.9 million.

The department said a number of harbors remain closed to ship traffic in the Houston-Galveston area, and waterways in Louisiana are also affected.

The Minerals Management Service said Ike destroyed 28 offshore production platforms in the Gulf. Twelve oil refineries in Texas and Louisiana remain shut down, the Energy Department said, and 19 major natural gas processing plants also remain shut down.

Catastrophe modelers estimate that insured losses from Ike will total between $6 billion and $18 billion.

According to IBHS, although Ike contained a large amount of energy, the storm spread moderately strong winds over a large geographic area, rather than very strong winds over a small area. Equipment from the University of Florida and Texas Tech University recorded wind gusts of 116 mph in rural areas about 50 miles northeast of Houston, but lower wind speeds closer to metropolitan areas.

IBHS said that from its preliminary observations, many buildings experienced roof sheathing and siding damage, consistent with a Category 2 hurricane. In some areas, only first floor windows were protected, leaving upper level windows exposed to flying debris. Commercial roof damage was extensive.

Newer residential constructed roofs performed well, while older homes suffered lost shingles and underlay. Commercial building damage in Houston appeared similar to damage to buildings in Fort Lauderdale and Miami following Hurricane Wilma in 2005, although not as extensive.

In the Galveston area, which suffered the brunt of Hurricane Ike, storm surge was the major cause of damage, IBHS said. Older buildings built below current flood elevation requirements suffered the most damage from the surge to lower levels and roofing.

Newer buildings that were properly elevated in accordance with modern building codes performed well, IBHS said.

The survey was carried out by Mr. Reinhold and researchers from the University of Florida, Texas Tech University, Florida International University, Louisiana State University and Clemson University.

Meanwhile, damage assessment from Hurricane Ike continues.

The Jersey City, N.J.-based Insurance Services Office Inc.'s subsidiary Property Claim Services (PCS) said it still does not have numbers to report on Ike.

PCS Assistant Vice President Gary Kerney said that many areas across the region are still inaccessible, “so it will take time to acquire the claim reports and compile an estimate for the nine affected states.

Originally, PCS applied catastrophe number 60 to the damage caused by Ike to Texas and Louisiana. Damaging weather from the remnants of Ike extended the catastrophe definition to include additional damage in the Midwest and lower Great Lakes regions.