For any property owner or manager in South Florida planning some sort of renovation, it is vital to understand the Florida Building Code (FBC) and its requirements. The Florida Building Code was created in 2000 in response to Hurricane Andrew in 1992. Before then, counties and cities could create their building codes so long as they met state minimums. However, Hurricane Andrew demonstrated how lax codes or poor enforcement could endanger lives and property and create a statewide disaster. Municipalities can make amendments that are stricter than the statewide code, but no local code can be lesser than the current edition of the FBC.

Florida Building Code Explained: Window and Door Replacement Requirements

The Florida Building Code is updated every 3 years to accommodate changes in climates, the housing market, and building material industries. The newest version of the FBC will go into effect January of 2021, and it will be referred to as Florida Building Code 2020 (FBC 2020), as it will be created this year. FBC 2020 will be the 7th edition of the Florida Building Code.

A common question among Florida property owners is "Are impact windows required in Florida?" The short answer is no. However, when it comes to replacing or installing new windows and doors, the Florida Building Code has very specific requirements as to what is acceptable. According to FBC 2017, the version currently being enforced in our state, all glazed openings within a structure need to either be impact-resistant or use impact coverings (like shutters). Some single-family homes can get approval for using plywood, but there must be pre-approved fastening systems in place.

All window and door projects, both replacement and new construction, need to be permitted with the local municipality. Therefore, no matter the type of product being installed, it must be proven to the building department when applying for the permit and during inspections that there is proper hurricane protection either installed or on property.

Since the Florida Building Code requires either shutters or hurricane windows (another name for impact windows), homeowners and property managers must decide which protection is right for their property. Since both options are acceptable within FBC 2017, the decision will likely come down to other factors like cost, labor, aesthetics, or what other additional benefits there may be. If you are trying to decide between hurricane shutters or impact windows and doors to protect your home and family, visit our shutters vs impact page to download a free copy of our comprehensive analysis on the subject.

South Florida is a unique place when it comes to home building, and windows and doors are no exception. While all of Florida must follow FBC, areas throughout South Florida, like South East Florida, have even more stringent codes. One such example is the High-Velocity Hurricane Zone, aka HVHZ. HVHZ is an area consisting of coastal Palm Beach County, Broward County, Miami-Dade County, and Monroe County. HVHZ requires stronger impact products than the other parts of Florida, meeting wind speeds between 170 mph and 200 mph, depending on your exact location.

Other areas in Florida require impact products or shutters that meet Wind-Borne Debris (WBD) certification. These products can be certified as impact-resistant but would not be authorized in the HVHZ unless they pass those tests as well.

Florida Wind Speed Map
Image Source: discover.pbcgov.org


How to Determine Your Required Design Pressures (DPs) 

Determining whether you are in the HVHZ is the first step in deciding the proper products needed for your project. The next consideration is what exposure the building is considered. Relation to large open areas (like bodies of water or large areas of flat land) and height of the building determines the exposure. Our entire service area falls under either Exposure C or Exposure D. Exposure C is for any building under 60 feet tall and that is at least 1,000 ft from a large open area. Exposure D is for any building within 1,000 ft of a large open area that is at least a mile wide, or any building that is above 60 ft tall no matter the location. Certain important infrastructure buildings like schools and hospitals must meet Exposure D requirements no matter their size or location.

Finally, within a single building, there are 2 different zones; zone 4 and zone 5. This is because the corners of buildings experience stronger forces from wind and flexion from the building moving during a storm. These zones are determined by the length of a single wall. Zone 5, which can require significantly higher negative design pressure ratings than zone 4, are any openings that are within 10% of the wall’s length from the corner. For example, for a wall measuring 20 ft, any opening within 2 ft of the corners would be considered zone 5 and need higher design pressures.

What Does This Mean for Your Window and Door Project? 

So, what do these requirements mean for you? First and foremost, the specific FBC requirements for your building will determine what design pressures (DPs) your new products, whether they are hurricane shutters or impact windows and doors, must meet. All these products must undergo both missile testing, which determines impact resistance, as well as cyclical testing. The cyclical testing determines the product’s design pressures, both positive and negative. These DP ratings refer to how much pressure, measured in pounds per square foot (psf), that the product can withstand before it breaks or is altered beyond acceptable parameters.

If your building is required to have high DPs, sometimes negative DP values for high-rises can be as high as -130psf, you may become more limited in size or material types for your hurricane protection. To meet the changing demands of the Florida Building Code, manufacturers are constantly innovating to create larger and stronger products. Impact window and door manufacturers like ESWindows and CGI Commercial offer aluminum windows as large as 15 ft tall and are approved for use in the HVHZ.

The Florida Building Code can be complicated to understand for those with little or no experience dealing with it. If you are considering new impact windows and doors, it is recommended that you speak with a seasoned professional who understands all these requirements and has access to a variety of product options to meet the demands of the FBC. To get a free consultation and estimate from the experts at Window & Door Replacement Company, fill out our form or call 561-623-8446.