The Importance of Hurricane Standards in Building Codes

28 Jun 2022

How building codes evolved to address hurricane impact hazards and where we are today

As the U.S. embarks on another hurricane season, safety – of people, of communities and of buildings – is top of mind. As discussed in a previous blog, damage from hurricanes, wildfires and tornadoes totaled $146 billion in costs last year. And this year's Atlantic hurricane season has been predicted to be above average by Colorado State University.

According to the Federal Emergency Management Agency (FEMA), one of the best ways to safeguard communities against natural disasters is adopting hazard-resistant building codes that ensure the safety and durability of structures. Building codes also help to mitigate the financial costs associated with damage, as well as casualties, as the strength and frequency of hurricanes continues to increase.

The development of hurricane standards in building codes progressed only in the last 50 years. In 1974, Tropical Cyclone Tracy in Darwin, Australia, resulted in the very first impact standard being defined in the Darwin Area Building Manual. In 1983, the Southern Building Code Congress International (SBCCI 1983) incorporated the impact standard used in the Darwin building code. Then in 1992 Hurricane Andrew hit southern Florida, causing extreme devastation and an estimated $25 billion damages. Two years later, hurricane mitigation provisions were defined for the first time ever in the Enhanced South Florida Building Code (Broward and Dade Counties). In 2002, the First Edition of the Florida Building Code adopted in the current, more modern format and in 2020 the current version of the Florida Building Code was adopted.

Hurricane Protection in Building Codes

I'm going to highlight some of the considerations that building codes in Florida and Texas have incorporated to help ensure the durability of structures during a hurricane. However, I also recently presented a webinar on Hurricane Standards, Testing and Product Approvals that goes into detail about all the requirements in the Florida and Texas building codes, as well as standards and test methods, product approvals, and best practices to consider when building in a hurricane-prone area. For a more in-depth look at hurricane standards and testing, download the recording.

The current edition of the Florida Building Code outlines requirements and definitions for buildings in areas where hurricanes are common. Chapter 2 of the Florida Building Code defines the following in relation to hurricanes:

• High Velocity Hurricane Zone – this zone consists of Broward and Dade counties.
• Hurricane-prone Regions – areas vulnerable to hurricanes, including the U. S. Atlantic Ocean and Gulf of Mexico
• Wind-borne Debris Region – areas within hurricane-prone regions

Chapter 16 of the Code discusses structural design requirements and testing for openings, roofs, vertical members, flooring, and shutters based on zone and region. Testing specifications are included for wind speed, deflection, missile impact, debris protection and other hazards associated with hurricanes. The Florida Building Code also references Testing Application Standards for testing, impact and non-impact building envelope components, and products subject to cyclic wind pressure loading testing.

It's a little different in Texas, where it is a home rule state. This means that building code adoption takes place at the local level, so adjacent municipalities may have different requirements. However, as of September 1, 2020, coastal properties must meet certain building standards to obtain windstorm insurance through the Texas Department of Insurance (TDI) Windstorm Inspection Program. The Windstorm Certificate of Compliance applications must be certified in accordance with the 2018 International Residential Code (IRC) or the 2018 International Building Code (IBC), regardless of municipality. Similar to Florida's Building Code, Texas also defines windborne debris protection, and most of the designated catastrophe areas are now located within the windborne debris region.

As you can see, while building codes have been revised in the last few decades to include provisions and requirements for hurricane impact, how they are adopted and implemented can vary state-to-state and even by municipalities within states. It's important to know and understand the requirements where you are to ensure you are building structures that can withstand weather events in your region.