Specific hurricane building code requirements are outlined in state and residential codes, which state the minimum safety standards that must be adhered to during house design, construction, and maintenance.
Requirements for hurricane windows and other hurricane protection measures can vary from state to state, so it can be a little tricky to determine the requirements for your area.
The importance of ensuring that buildings are designed, built, and maintained using current best practices cannot be overstated.
From 2018 to 2020, 10 hurricanes battered the coastline of the United States. In 2020, convective storms led to over $30 billion in damage, with $11 billion lost during a single event classified as a derecho that occurred in August 2020.
A derecho is a long-duration, widespread storm that forms from a cluster of thunderstorms or a single high-energy storm. They can cause similar destruction to hurricanes, but the damage is generally in one direction, extending more than 240 miles and with gusts of wind above 58 mph.
Whatever label is put on it, a storm can represent an existential threat to your home, blowing in your windows, lifting your roof clean off, and razing the house to the ground. Your windows are an essential line of defense against hurricanes and other intense storms.
Following the requirements of the building codes in your area won’t guarantee that your home will escape any storm damage, but it will go a long way to making sure it survives and remains in a livable condition.
Table of Contents
- Are Hurricane Windows Required In My State?
- What Risks do Hurricanes Pose?
- What Are the Options for Protecting Windows from Hurricanes?
- What Are Building Codes?
- What Are the Hurricane Window Code Requirements for Distinct States?
Are Hurricane Windows Required In My State?
Hurricane windows are not specifically required in most states at risk of hurricanes. However, building codes in at-risk areas often require window protection measures, such as shutters or plywood boarding to avoid damage from flying objects and high winds.
If you’re considering installing hurricane windows, either because of recent damage to your home or because you are building a new home from scratch, it’s essential to understand the requirements of your local jurisdiction.
The hurricane window building codes for your area must be considered when making significant changes to your home.
Ensuring that your home meets requirements is not just about passing the inspection. It can also influence the amount you pay on your home insurance, not to mention ensuring your windows are up to the task of fending off the worst a hurricane or other substantial storm can throw at your home.
There are many measures that homeowners can employ to improve their home’s resilience to hurricanes. In addition, many can reduce the cost of home insurance.
We’ve published an article on one of these measures, hurricane ties, and how much installing them can save you on home insurance.
For this post, we’ve put in the legwork to identify standard requirements for hurricane windows under the building codes of some of the states most affected by hurricanes.
So, read on to find out more about this critical topic.
What Risks do Hurricanes Pose?
Hurricanes wreak billions of dollars worth of damage each year in the US. We’ve all seen the pictures of devastation on the news, with buildings flattened, cars wrecked, and people injured or killed.
These tropical cyclones are generated by warm surface sea temperatures in the Atlantic Ocean, which make moist warm air rise into an overhead storm, causing the low-pressure area beneath to intensify.
As more air is drawn into the storm, it rises and cools, resulting in the formation of more clouds as the moisture condenses. This process generates heat, causing the storm to get stronger.
When the hurricane makes landfall, its strong winds and torrential rain often damage property and endanger life. These powerful storms have killed almost 7,000 people since 1980.
The states along the Atlantic Coast of the US and the Gulf of Mexico are most at risk. Florida suffers the most hurricanes by a considerable margin, as seen in the graph below.
Hurricanes bring high winds, which can lift objects from the ground and propel them through the air at an alarming speed. When these flying objects collide with buildings, they can cause damage, especially to windows, the weakest point of most homes.
Once a smashed window has compromised the building envelope, wind and rain rush in.
The resulting water damage is often nothing compared to the devastating impact of the wind blasting through the window opening, causing a rapid increase in air pressure that can rip the roof off and topple the walls. In which case, the outcome for your home will be complete destruction.
Another concern of hurricanes is the severe rainfall, which can produce flooding, damage people’s homes, and threaten lives. Storm surges, rip tides, and tornadoes are also possible, and further add to the hazards faced by the population when a hurricane hits.
What Are the Options for Protecting Windows from Hurricanes?
You can take precautions to protect your home’s windows from the worst effects of a hurricane.
Some of the best measures include:
Boarding Up Your Windows
The most basic option for protecting windows is to place plywood sheets or other protective panels over them, which are a physical barrier to flying objects. Although this is a relatively cheap option, it requires work every time a hurricane warning is issued.
The plywood needs to be stored when not in use and needs a thickness of 5/8″ as a minimum to be strong enough to withstand the punishment a strong storm can dish out.
Plywood boards can also be challenging to install on second-story windows, and you might not relish the prospect of climbing up a ladder with a heavy, unwieldy piece of plywood, especially if the wind is already getting up.
Resin-Coated Ballistic Nylon
Easier to handle and install, resin-coated ballistic nylon can protect your windows from the wind and rain, but the material flexes when hit by a large object, which can allow the window to be smashed.
Permanently installed on the outside of the home, hurricane shutters are an effective protective measure that homeowners can easily draw across the windows of their home in response to a hurricane warning.
Although some types will still require you to climb a ladder to close them if they are located on the second floor, some can be shut from inside the house. Shutters that can be closed remotely are also available, which makes for a very convenient solution.
Hurricane windows are made from laminated glass, comprising two or more layers of clear glass with a piece of plastic film.
These layers are bonded together to make a robust pane of glass that can withstand impacts from flying objects such as those it might expect to receive during a hurricane.
The plastic center of the sandwich is typically made from polyvinyl butyral and is at least 0.015 inches thick but could be as wide as 0.09 inches. If the pane suffers an impact, the plastic layer holds everything together even if the glass smashes because the fragments generally stick to the plastic.
This durability maintains the building envelope and obstructs wind and rain from rushing in, stopping water damage to your belongings. More importantly, it prevents the sudden increase in pressure that can lift your roof off and blow your whole house down.
The great thing about hurricane windows, apart from their protective features, is that they are a completely passive measure, meaning you don’t need to do anything to prepare for an approaching storm.
Hurricane windows are ready to protect upon installation, making them a great option if you are often away from home and won’t necessarily be there to respond to a hurricane warning, which will only come 36 hours before its arrival.
They are also great options for people with mobility issues who would struggle with the task of fitting protective panels before a storm arrives.
What Are Building Codes?
Building codes have been developed for most aspects of US building design, construction, and maintenance. Residential codes provide guidelines on how to build homes and have been available in the US for over a century.
Building your home to meet the requirements of the relevant codes will ensure you meet the minimum legal provisions. The standards set out in the building code guidelines are the minimum stipulations needed to protect the general welfare, safety, and health of those living in the building.
The codes are regularly updated to ensure they remain relevant and account for modern innovations, research lessons, and recent disasters. The codes’ requirements are usually specified in terms of the minimum performance required or in prescriptive statements.
Performance codes set a technical objective, and it is up to the designers and builders to determine how to meet the standard.
An example of a performance-based code requirement is the specification for an impact window, which must be able to withstand an impact from a piece of 4″ x 2″ lumber fired at it at a speed of 34 mph and then survive 9,000 cycles of wind testing.
Prescriptive codes, on the other hand, specify the precise method that designers and builders must follow to achieve the objective.
What Are the Hurricane Window Code Requirements for Distinct States?
To help you get a feel for the requirements of different states and how your local specifications stack up against other parts of the country, we’ve compiled a list of requirements for some of the key states affected by hurricanes.
If your state isn’t included in the list below, you can find out what the requirements are for your locality by checking this website, where you can enter your zip code or address to get the full details.
The best way to find out what your particular jurisdiction requires is to speak to the local authority for your area. They will advise you on what is needed, and you should always talk to them to be clear on things.
US States With Statewide Hurricane Window Codes
Eighteen states along the Gulf and Atlantic coasts are classed as most vulnerable to catastrophic hurricanes.
Every three years, the Insurance Institute for Business & Home Safety (IBHS) produces a report called “Rating the States,” which evaluates the building code enforcement and administration and the licensing of contractors in these states.
According to the 2021 IBHS report, ten states have uniform statewide codes and enforcement processes for residential buildings, including:
- South Carolina
- New Jersey
- Rhode Island
- North Carolina
States With No Mandatory Codes
According to the IBHS report, eight of the eighteen most vulnerable to catastrophic hurricanes have no mandatory statewide codes.
These states include:
- New York
- New Hampshire
Some states mentioned above have changed their regulations since the IBHS report was published and now have statewide codes. For example, Alabama is one which has now adopted the 2021 International Building Code.
This change was announced on April 11, 2022, and takes effect July 1, 2022, with a six-month grace period to allow projects already underway to complete the review process or transition to the new code requirements.
Let’s look at some of these states in a bit more detail.
Florida is widely acknowledged as the leading state in the US regarding hurricane safety requirements set out in its building codes. This stringency is perhaps not surprising given its susceptibility to hurricanes, as shown above.
The 7th Edition of the Florida Building Code, Residential (FBCR) was brought in in 2020, updating the statewide code put in place in 2017. The code’s requirements cover the protection of households from wind, fire, flood, and storm surges and are based on the latest technical requirements and research.
The Florida Building Code requires windows to be impact-resistant or protected (with shutters or protective panels) if they are located less than a mile from the sea and if the wind speed is 110 mph or more.
Florida also has a hurricane tie and strap code, which we’ve written about here if you want to learn more.
The 70th Texas Legislature passed House Bill 2012, which put in place requirements for the inspection of structures to be considered insurable for hail and windstorm insurance cover via the Texas Windstorm Insurance Association (TWIA).
Any new repairs, construction, or additions must be inspected to ensure they adhere to the TWIA Plan of Operation. The inspection program relates to the houses in “catastrophe areas,” as the Texas Department of Insurance Commissioner specifies.
Some examples of areas designated as “catastrophe areas” include:
Cameron County requires window and door protection to withstand windborne debris impacts, such as permanently-mounted hurricane shutters, temporary panels for covering the windows with permanently-installed mounting hardware, or replacement products that significantly increase protection for windows and doors.
According to the Brazoria County website, as recently as 2018, it had not adopted building codes for single-family residential developments.
This means that hurricane windows, shutters, or protective wood panels are acceptable for one- and two-story single-family dwellings.
Galveston has adopted the 2012 International Residential Code, meaning there is a requirement for hurricane shutters, temporary panels, or replacement products to increase windows and doors’ protection significantly.
Louisiana has implemented a uniform statewide code that includes requirements that protect homes from hurricanes.
These include specifications that, in windborne debris regions, glazing must be resistant to impact or protected with a covering capable of withstanding impacts from flying debris.
If windows are not impact-resistant hurricane windows, they must be protected by wood structural panels of at least 7/16″-thickness. Greenhouses and glazing over 30 feet are exempt from the protection requirements.
Alabama has adopted the 2021 International Building Code as the State Building Code, meaning that impact-resistant hurricane windows are required in windborne debris regions.
If windows are not impact-resistant, shutters or protective panels are acceptable.
According to the Georgia government website, buildings must be designed for impact resistance. The website states that all components of the exterior building envelope must be impact resistant or covered by a protective impact-resistant covering (such as shutters).
South Carolina’s website states that a home’s windows, doors, and skylights must be protected from impact by windborne debris by one of the following:
- Impact-rated hurricane windows
- Shutters, including roll (either fabric or metal), Accordion, Bahama, and Colonial
- Temporary storm panels made from steel, aluminum, or polycarbonate
- Screen or fabric specialist protective measures
- Structural wood, such as plywood panels
North Carolina’s State Building Code is based on the 2015 International Residential Code.
Requirements for hurricane windows in buildings that are in windborne debris regions are that they must meet the standard of the Large Missile Test of ASTM E 1996 and ASTM E 1886.
In single and two-story buildings, wood structural panels are permitted for use as protection, provided they are at least 7/16″-thick, with a maximum span of eight feet. The panels must be pre-cut and pre-drilled to be secured with the hardware provided.
According to the 2018 Virginia Residential Code, exterior glazing of buildings in windborne debris regions needs to be protected from windborne debris.
Building owners must achieve this with protection that meets the requirements of the Large Missile Test of ASTM E1996 and ASTM E1886. These tests apply to exterior windows and also protective systems such as shutters.
The Virginia code does allow for wood structural panels to be used to protect windows, provided it is at least 7/16″-thick and has a span of fewer than eight feet.
The panels must be pre-cut and attached to the window frame. They must also be pre-drilled and secured with the necessary hardware to resist the loads they are likely to experience.
The damage caused by hurricanes each year is massive. Intense storms are responsible for significant loss of life and result in costly repair or rebuild bills for residents of impacted areas when they land.
Windows are particularly vulnerable during a hurricane and can be pierced by flying objects picked up by the high winds.
When this happens, it allows wind and rain into the house, causing extensive damage. The sudden inrush of current can even raise the air pressure inside the house enough to lift the roof off and eradicate the building.
Protective measures are available that can reduce the likelihood of damage to a house. Such efforts include hurricane windows, shutters, and temporary protective wooden panels.
These are not only good practices but are code requirements in most states prone to hurricanes.
Specific code requirements vary between jurisdictions, but they share the principle of protecting window openings by ensuring the window is strong enough to survive an impact or by shielding it with a protective covering.
These precautions decrease the chance of a building envelope breach, keeping the wind and rain out of the house. This security protects the contents from water damage and, perhaps more importantly, safeguards against the severe structural damage that can result from the inrush of high winds.