Hurricane season is here and, for many Florida residents, it’s time to verify your hurricane preparedness. Let’s start with talking about what a high velocity hurricane zone in Florida is and what it means for your hurricane prep.
Knowing whether your home is in a high-velocity hurricane zone (HVHZ) or not can have a huge impact on the kinds of preparations you need to make for your home.
What Does High-Velocity Hurricane Zone Mean in Florida?
A high-velocity hurricane zone is a region where the Florida Building Code requires structures to be built to withstand wind loads between 156 mph to 186 mph for three-second gusts, depending on the “risk category’ of the structure and which county it’s in.
A hurricane with sustained winds of over 155 miles per hour is considered a Category 5 hurricane, as noted by the Commander, Navy Region Southeast website.
Micheal, the Category 5 hurricane that hit Florida in 2018, was the most powerful hurricane to hit Florida at the time and wrought devastation all the way up north to Georgia after making landfall in Florida. Milton, which hit Florida in 2024 right after Hurricane Helene, had briefly reached Cat 5 status before weakening prior to making landfall.
In Florida, the term HVHZ might only specifically apply to Miami-Dade and Broward counties, every homeowner in the state should prepare like they live in a high velocity hurricane zone. This begins with reinforcing your home’s biggest weak points during a storm: your windows and doors.
What to Look For in an HVHZ Window or Door
In a major hurricane, the windows and doors of your home are the most likely points of failure. And, when a window or door goes, the rest of the house may soon follow. A window or door holding after being hit with a large piece of debris or being subjected to constant changes in air pressure can mean the difference between a house still standing and it being destroyed by hurricane-force winds.
So, the #1 thing to look for in a high-velocity hurricane zone window or door is its durability. An HVHZ window needs to be tough enough to withstand massive wind pressure and heavy impacts from wind-blown debris.
How Much Wind Does It Take to Launch Something at My Home?
The amount of wind that it takes to launch an object through the air varies depending on the weight and surface area of the object. There’s a news story that shared a helpful formula that can give you a rough estimate of the wind speed needed to move an object: W = √195 x (weight in pounds / Area in sq. ft.).
So, say you have a car that weighs 2,000 pounds and has a surface area of 80 sq. ft. being hit by the wind. A wind speed of just 70 mph would be enough to move the car. The heavier and smaller the object, the harder it is to move, and the larger and lighter it is, the easier it is to move.
A category 5 hurricane puts out winds stronger than 155 mph. More than twice the wind speed required to move the car from the example.
What Features Should a High Velocity Hurricane Zone Florida Window Have?
Aside from pure durability from being made of impact glass, what features should a window rated for an HVHZ area have? Some key features of an HVHZ-rated window include:
- Laminated Glass. Even the strongest windows can only take so many impacts before shattering. One of the ways that windows made for high velocity hurricane zones protects homes is by including a layer of laminate that flexes rather than breaks when the harder glass is broken by an impact.
- Multiple Layers. Many HVHZ windows have two or more layers of glass to isolate the interior of the home from the outside air. When an impact shatters the outer glass, the inner glass remains to continue holding back the wind and rain.
- Reinforced Frames. It doesn’t matter how tough the glass is if the frame holding it fails. Hurricane windows need to have tough frames that can take being hit with heavy debris without failing. If the frame bends or breaks excessively, it can cause the whole window to fail.
- Expert Installation. To provide maximum protection, an impact window for HVHZ zones needs to be installed the right way. This means the installer should never cut corners during the installation. Poorly-done installations can mean the window doesn’t sit right in your home or may be more prone to simply falling out during a hurricane. Always look for a highly-rated and trusted window replacement company that uses in-house contractors instead of outsourcing to unreliable third party contractors.
Will an HVHZ Window Never Break?
High velocity hurricane zone-rated windows are incredibly tough and won’t break easily. However, they aren’t completely impervious to impacts. A heavy enough object hitting the window hard enough will cause even the strongest impact glass to break.
What separates a hurricane-rated impact window from a window that’s simply tough is that the hurricane window is designed with failure states in mind.
For example, if the outer window glass breaks, Simonton’s StormBreaker windows will have a flexible layer of laminate behind the window to keep the wind and rain at bay. Behind that is a separate pane of glass that, if a small hole is torn in the flexible laminate, will still work to keep out wind and rain.
After such a break during a storm, the whole window will need to be replaced, but that’s far better than having to pay for water damage remediation on top of replacing the window.
Is My Home in a Florida High Velocity Hurricane Zone?
Currently, only Miami-Dade County and Broward County are designated as high-velocity hurricane zones in Florida.
However, they aren’t the only regions that can face the brunt of a Category 5 hurricane. It’s just that these two counties have been specifically called out as facing a higher risk of being directly impacted by high-velocity hurricanes compared to other parts of Florida.
So, even though your home in Pinellas, Pasco, or Hillsborough county might not be specifically part of a high-velocity hurricane zone, it’s still important to prepare for hurricanes that have high wind speeds.
This is why many homeowners throughout the counties surrounding Tampa look for HVHZ-rated windows that have the Miami-Dade seal of approval, despite not being in Miami-Dade County.
These windows will have passed Missile Impact D tests proving their durability against the kinds of hits a hurricane can throw.
Get High Velocity Hurricane Zone-Rated Windows!
Even if you don’t live in one of Florida’s high velocity hurricane zones, upgrading to HVHZ windows can be an important upgrade—especially with hurricane season already underway as of the time of this writing.
Get prepared for hurricane season by installing high velocity hurricane zone Florida windows from Tampa Bay’s #1 most trusted window replacement company.
Our dedicated team of in-house contractors do the job the right way, every time. With HVHZ windows, you need to ensure that the team putting your windows in is a team you can trust. Reach out to Karoly Windows & Doors to get a quote for HVHZ windows and doors for your home!
