The Resilience of Closed-Cell Spray Foam: Weathering the Storm
Hurricanes are among the most destructive natural disasters, primarily due to their powerful winds. The National Hurricane Center has established the Saffir-Simpson Hurricane Wind Scale (SSHWS) to categorize hurricanes on a scale from Category 1 to Category 5, based on their sustained wind speeds. Category 5 hurricanes are the most formidable. Hurricanes officially begin at Category 1 when they reach sustained winds of 74 mph. These hurricanes can unleash sustained high winds for hours, often accompanied by gusts reaching 50 percent higher than the sustained wind speed. A Category 2 hurricane, with minimum winds of 96 mph and gusts of up to 144 mph, can exert nearly 80 pounds of pressure per square foot, posing a severe test for traditional home construction.
The Perfect Example
The Sand Palace in Mexico Beach, Florida, provides a real-world example of hurricane-resilient construction. It withstood the devastation of Category 5 Hurricane Michael in 2018 due to its fortification with six inches of closed-cell spray foam insulation, which not only improved insulation but also increased its structural strength by up to 300 percent.
Research and reports have demonstrated the effectiveness of closed-cell spray foam insulation in hurricane-prone regions. The National Institute of Standards and Technology found that spray polyurethane foam (SPF) roofing systems held up well during Category 3 hurricanes like Katrina and Rita. Additionally, the Spray Polyurethane Foam Alliance (SPFA) conducted tests revealing that closed-cell spray foam insulation significantly enhances transverse and lateral shear strength, up to 300 percent, in both metal and wood construction.
In response to the growing threat of major storms, building codes in hurricane-prone areas, such as Miami-Dade County, have evolved. They now require measures like bonding roof sheathing to attic framing and walls. FEMA-approved closed-cell spray foam insulation, not only meets wind uplift prevention requirements but also fulfills energy insulation codes, ensuring homes are better prepared for the increasing danger of powerful hurricanes.