Everything You Need to Know About Hurricane Windows

According to the National Oceanic and Atmospheric Administration (NOAA), more than 300 hurricanes have struck the United States since 1851. Of these, almost one-third have been Category 3, 4 or 5 storms.

States that border the Atlantic Ocean and the Gulf of Mexico are most at risk, with Florida the clear leader in the number of hurricanes making landfall. Building codes in many parts of that state mandate hurricane windows or hurricane shutters, which offer protection from high winds. Since 2012, the International Building Code required them in new construction in coastal states from Texas to Maine.

During a hurricane, strong winds can lift debris and hurl it through the air at high speeds. When it strikes windows, flying shards of shattered glass pose a hazard to anyone in the vicinity. And with the glass gone, there’s nothing to stop the wind and rain from damaging the inside of the structure. Hurricane windows can prevent all that.

What Are Hurricane Windows?

Windows designed to stand up to hurricane-force winds and flying debris.

Instead of a single pane, hurricane windows feature two panes of tempered or laminated glass, bonded to a central layer of clear polymer (usually polyvinyl butyral). The glass shatters when struck by a projectile. But instead of flying in all directions, it clings to the central plastic layer, which remains intact to seal out wind and rain.

Hurricane windows come with strong frames, usually wood or steel. Some budget-friendly windows may have vinyl or aluminum frames. To provide the maximum level of protection, hurricane windows need to be professionally installed.

Hurricane Windows vs. Impact Windows: What’s the Difference?

Hurricane-resistant and impact-resistant windows are almost the same thing. The difference: Hurricane windows must meet building codes in hurricane-prone areas. They undergo one of two tests, depending on where they’re placed on a building.

Windows installed below 35 feet above ground must withstand the impact of a 2×4 fired at the glass from a cannon at around 50 feet per second. Those above 35 feet are tested differently, with a large number of ball bearings fired at the glass. Two tests are needed because the force of debris in the air during a hurricane varies with altitude.

Hurricane windows sold in Florida must be approved by the state or Broward and Miami-Dade Counties. The latter two, in South Florida, carry more stringent requirements because hurricanes in that region, known as the High Velocity Hurricane Zone (HVHZ), are stronger than anywhere else.

Hurricane windows in other states don’t have to conform to Florida standards. But if they do, it’s a selling point.

Types of Hurricane Windows

Each hurricane window receives a design pressure (DP) rating based on the maximum pressure differential it can withstand. It’s a complex formula that corresponds to storm intensity.

A DP rating of 10 should withstand a Category 1 hurricane (maximum wind speed 95 mph). A 20 rating should withstand a Category 2, and so on, up to DP 5 for a Category 5 storm (maximum wind speed exceeding 157 mph).

Hurricane windows are available in seven formats, including:

• Single-hung;
• Double-hung;
• Bay;
• Sliding/rolling;
• Picture/fixed;
• Casement;
• Skylight.

Dealers stock windows in standard sizes, designated by a four-number code. A standard 24- by 36-inch bedroom window bears the code 2436. Most dealers also accept orders for non-standard sizes.

Benefits of Hurricane Windows

If you live in hurricane country, the benefit is obvious. There’s no need to add storm shutters or cover your windows with plywood, which Floridians turned to in the past when storms approached. There are other benefits as well.

• Noise reduction: Hurricane windows are thicker than conventional single-pane windows, making your house quieter.
• UV protection: The laminated glass, as well as the central polymer layer, naturally filter out harsh sunlight, even without a UV-blocking film.
• Energy efficiency: Hurricane windows provide better thermal insulation than regular ones.
• Home security: Windows that can withstand a hurricane can also stand up to intruders trying to break them and get into your house.

The No. 1 drawback to hurricane windows is the expense (see below). They’re not only costly to purchase and install, but more costly than conventional windows to replace if they do break. Besides that, design options are more limited than conventional windows.

Cost of Hurricane Windows

The average cost to equip an entire home with hurricane windows is around $8,000. The factors that influence costs include:

• Window size and location: It costs more in labor to install windows in upper stories.
• Frame material: Wood is the most expensive, and aluminum the cheapest.
• Special features: Adding stabilizer bars or low-emissivity glass costs more.
• Permits: These costs vary from place to place but are generally between $50 and $200.

Homeowners in hurricane hotspots can save money on installation by doing it during the off-season. And all homeowners installing new hurricane windows can take advantage of a $200-per-window federal tax credit provided by the Bipartisan Budget Act of 2018.