Impact resistant windows, also known as hurricane windows, are designed and made to withstand high winds (up to 170 mph) and resist shattering when struck.
While impact windows aren't indestructible, they are very hard to break. To get through, a burglar would create a ruckus and likely be caught. Breaking through impact windows typically proves to be considerable work and energy, forcing burglars to move on.
Impact glass is designed to resist heavy blows, and for this reason, it has become the mainstay in windshields for cars, trucks, and busses and more recently houses windows. Just like a car windshield, however, it can break if hit hard enough.
Installing these windows significantly lowers your chances of major damage to your home. Hurricane impact windows have advanced to the point where they can withstand Category 5 wind conditions, and the debris that goes with it. So next time a hurricane hits your neighborhood, don't be caught unprotected.
Impact Windows Are Just for Looks
Knowing that your home has permanent protection against hurricanes, tornadoes, and other storms at any given time also provides peace of mind. Ultimately, hurricane-resistant windows are capable of withstanding winds of up to 200 miles per hour.
There is a common misconception that hurricane windows and doors are “impact-proof”, but that is not true. They are called impact windows because they are impact-resistant, not impact-proof. The glass may crack when it's hit, but it will not break into pieces, or break away from the frame.
Hurricane windows are treated with a laminate that prevents the glass from breaking but does not stop a bullet from passing through them. These windows are designed to protect against flying debris caused by hurricane winds. So, to answer your question, no, hurricane or impact windows aren't bulletproof.
All PGT WinGuard® windows and doors are rated for Impact Zone 3 and Impact Zone 4 ratings and are tested to withstand winds over 150 miles per hour in accordance with the ASCE Wind Zone Map.
Category 4 Hurricane
These winds can destroy a home's roof structure and exterior walls, topple most trees and power lines, and cause damage that will last for months. Category 4 hurricanes cause extreme harm to glass windows and doors for homes and businesses.
Most older homes have windows that do not latch, close, or operate properly which can be a nuisance and could also be dangerous in hurricanes; even with hurricane shutters on. With impact hurricane windows and doors you do not need hurricane shutters.
The biggest drawback of impact windows is their cost, which is why they are typically only used in high-risk areas. However, it is beneficial in the long run because they last much longer than other types of glass.
Aluminium windows are considered one of the most secure options available on the market. It is one of the most burglar resistant materials available because of its inherently strong properties despite its featherweight appearance. When discussing aluminium's durability, it's much stronger than most people realise.
A polycarbonate window is much more difficult to break through than a standard glass window. In fact, according to some estimates a polycarbonate window is over 200 times more resistant to impact!
How much force does it take to break a house window? Depending on the manufacturer, the force required to break tempered glass ranges from 20,000 to 24,000 PSI (or pounds per square inch).
You don't want to spoil anyone's fun by telling them not to play because you're worried about your windows. With impact windows, you can let them play and they can even keep playing after a ball hits your glass because it won't break.
In plain terms, yes, impact glass can break. However, as these glass structures receive impact, the inner layer of PVB keeps the structure from breaking down—it keeps the window standing even though the glass shatters. There are varying types of impact glass.
After moving west across south Florida and into the very warm waters of the Gulf of Mexico, Katrina intensified rapidly and attained Category 5 status (with peak sustained winds of 175mph) for a period of time as it moved northwest on August 28th.
According to Ocean Impact Windows, standard residential windows typically can be expected to sustain winds up to 77 mph before shattering. More advance windows are able to sustain winds up to 173 mph!
A Category 7 is a hypothetical rating beyond the maximum rating of Category 5. A storm of this magnitude would most likely have winds between 215 and 245 mph, with a minimum pressure between 820-845 millibars.
So with all that said, at what wind speed do windows break? A Design Pressure or DP rating measures the strength of a window. Standard residential windows have DP values between 15 and 50. A DP 15 window can reasonably be expected to sustain winds of roughly 77 mph before shattering.
Impact windows are oftentimes worth the money. Though they're typically more costly than standard windows, the impact options can reduce the price of your home insurance and help prevent costly home damages caused by storms.
Category 1: 74-95 mph. Category 2: 96-110 mph. Category 3: 111-129 mph. Category 4: 130-156 mph.
Impact resistant windows and doors are made to withstand impact and not break into pieces regardless of whether the impact comes from hurricane-force winds, flying debris or a hammer.
Impact-resistant windows are designed to withstand impact from debris at high speed, whether it's from a hurricane, tornado, or even a burglar. If you aren't currently ready or willing to replace all of your home's windows, you can also install shutters to protect your current windows from hurricanes.