IBHS has conducted several damage investigations following major hurricanes to assess building performance across different wind speed zones, exposures, and construction eras. All data are georeferenced and focus on details such as terrain exposure, elevation and roof structures, finishes, openings and opening protection, attached structures, and damage to these building systems.
A major finding from our post-disaster investigations and research is that stronger building codes significantly improve the performance of houses during a hurricane.
More than $9 trillion of insured coastal property is vulnerable to hurricanes along the Gulf and Atlantic coasts from Texas to Maine. Additionally, 50 percent of the nation’s population now lives within 50 miles of the coast.
On September 14, 2018, Hurricane Florence made landfall near Wrightsville Beach, North Carolina, with sustained winds of 90 mph. Florence moved slowly inland with heavy rain and tropical storm conditions extending over a large area. On September 24–27, the IBHS Post‐Disaster Investigation Team deployed to assess residences along the North Carolina coast from Wrightsville Beach to Pine Knoll Shores. This area included wind speed zones from 80 mph to 105 mph based on 3‐sec gust RMS HWIND wind speeds. The team conducted on‐site visual inspections and used drone and NOAA aerial imagery to evaluate the performance of the roofs of FORTIFIED houses. The team investigated a total of 55 homes, consisting of 22 FORTIFIED houses and 33 non‐FORTIFIED neighboring houses.
[Members Only] General Insights on Performance of FORTIFIED Residences in Hurricane Florence
A post-disaster study of the coastal wind damage caused by Hurricane Harvey in 2017, resulted in important new guidance for people with homes exposed to hurricane winds. The report also offers new quantitative data that will help architects and building designers, insurers and catastrophe modelers better understand how storms affect structures.
This report offers coastal communities, and homeowners anywhere high winds occur, excellent guidance on how to defend against high winds. It is based on a coordinated, scientific field assessment of how structures of various ages, designs and construction techniques fared against Hurricane Harvey’s Category 4 conditions.
Hurricane Harvey Wind Damage Investigation
Hurricane Harvey Wind Damage Investigation – Summary
Hurricane Isaac was the first hurricane to make landfall in the continental United States in 2012, and the first since Hurricane Irene in September 2011. Isaac became a Category 1 hurricane shortly before it made landfall near the mouth of the Mississippi River in southeastern Louisiana. Tropical storm conditions persisted over southeast Louisiana and coastal Mississippi for almost 18 hours. This storm had a large wind field, a storm surge of up to 12 ft and significant rainfall (greater than 10 in. in most areas).
This report summarizes the evolution of Isaac, the primary storm hazards, and their impact at landfall along the northern Gulf Coast. Available data from various observation systems (including Texas Tech University Hurricane Research Team platforms) were compiled to provide a summary of wind, storm surge, and rainfall measurements.
Hurricane Isaac Report
When Hurricanes Gustav and Ike raked the coastlines of Louisiana and Texas in 2008, researchers from the Institute for Business & Home Safety (IBHS) and the University of Florida (UF) were presented with a valuable opportunity to investigate the performance of asphalt shingle roofs in real-world storm conditions.
In 2008 Hurricane Ike made landfall on the Bolivar Peninsula (a 27-mile-long barrier island north of Galveston, Texas) and devastated most of the homes with wind gusts up to 115 mph, a 15–20 ft storm surge and heavy rains. Both in the size of its cloud mass and the total energy it contained, Ike was unlike any other hurricane that modern science has been able to observe in the Gulf of Mexico.
After the storm, 10 homes built to a first-generation FORTIFIED standard were among the last houses standing. Upon closer inspection, IBHS engineers found those homes survived with little damage and performed as intended under the fury of this powerful hurricane.
The impact of this hurricane on the Texas coast presented researchers with a valuable opportunity to observe the real-world performance of building materials, product standards and construction techniques. It also provided the first performance test of homes constructed to IBHS’s FORTIFIED standards. This report provides guidance on strengthening coastal construction based on those real-world performance results.
When Hurricane Katrina made landfall on August 29, 2005, it caused an estimated $41.1 billion in insured losses across six states and took an incalculable economic and social toll on many communities. In two reports, one 5 years and one 10 years after Katrina, IBHS examined the aftermath of recovery in the most severely affected states of Alabama, Louisiana and Mississippi.
The 5 year retrospective looked at recovery efforts, changes in building codes and code enforcement.
The 10 year retrospective also examined the effects of enactment of stronger building codes, standards and requirements in several areas. IBHS examined changes specific to roofing requirements during the last ten years in these communities and evaluated several key aspects of roofing regulations, such as building codes, contractor licensing, permits and inspections.
To assess roof regulation improvements along the Gulf Coast, IBHS collected and analyzed data from 40 of the 42 coastal communities in Alabama, Louisiana and Mississippi with populations of at least 10,000. The results of the analysis include recommendations for stronger permitting requirements, and improved roof construction methods in line with our FORTIFIED program requirements.
Hurricane Charley in 2004 was the start of one of the busiest hurricane seasons in the U.S., damaging one in five Florida homes. When it made landfall, Charley had the highest winds of any storm to hit the U.S. since Hurricane Andrew in 1992, and clearly demonstrated the benefits of strong building practices.
IBHS conducted a study of closed insurance claims in 2004, in Charlotte County, Florida, where Charley made landfall. While Charley caused significant damage, the study found the frequency of damage was reduced by 40 percent, and the severity of damage was reduced by 60 percent to homes built after 1996, when stricter building codes went into effect in the area.