When it comes to window glass, there are a few different types that you might come across. The most common is standard window glass, also called “annealed glass” which is found in most older homes. Then there’s tempered window glass, which is designed to break more safely into smaller pieces, compared to standard glass.
In most places throughout the United States, smaller windows are usually made with annealed glass, while large windows and glass doors have tempered glass.
Annealed glass can break into sharp shards. For a small window this is believed to be less of an issue. Whereas large windows and glass doors will have tempered glass, sometimes called safety glass, that breaks into tiny pieces which are less likely to cause serious injury in the event of an accident.
In contrast to these traditional windows used in most of the country, hurricane impact windows are made differently. Impact-glass is laminated glass. Laminated glass is actually two panes of glass sandwiched together with a super-strong flexible interlayer in the middle. It is sometimes referred to as monolithic glass. The laminated glass is how impact windows are able to hold up to hurricane force winds and flying debris.
If you’re looking for a window that is both strong enough to withstand Florida hurricanes and offers crystal-clear views, impact windows with laminated glass may be the perfect option for you.
Another difference is that hurricane windows often have laminated glass that is heat strengthened. Today, we are going to review how laminated glass differs from tempered glass and annealed glass. First, let’s begin with the science behind them.
How Heat Strengthened and Tempered Glass Windows Are Made
To understand how heat strengthened and tempered glass windows work, it’s important to know a little bit about the manufacturing process.
The process begins and the glass is thoroughly inspected for any flaws that could cause it to break before or during the heating process.
Once it passes inspection, the glass is heated to around 1200 degrees Fahrenheit (approx. 648 degrees Celsius) with the use of a tempering oven.
The difference between heat strengthened and tempered glass is what happens afterwards. Heat strengthened glass is cooled slowly. Whereas tempered glass is quickly cooled in a high-pressure environment. This process, called “quenching” cools the exterior surface of the glass most quickly.
As the center remains hotter for longer, it creates a state of tension while the outer surface remains in a state of compression. This results in the unique characteristics of tempered glass.
Another, less common, way to temper glass is to use a combination of chemicals that stimulate compression. However, this is usually a more costly process compared to traditional tempering and quenching.
Annealed vs Heat Strengthened vs Tempered Glass
Heat strengthened glass is about twice as strong as annealed glass. Tempered glass is also much stronger than annealed glass. However, tempered glass generally has more distortion than heat strengthened glass due to the rapid cooling process.
This means heat strengthened glass has a flatter surface and gives a better and less distorted view than tempered glass does. This is one of the reasons why car windshields are usually made from laminated glass rather than tempered glass.
Applications for Tempered Glass
Tempered glass is widely used across many applications and industries. Some of the most popular examples include:
Non Impact Windows
Most traditional residential and commercial storefront windows are made from tempered glass for safety.
Automotive Side and Rear Windows
You’ll also find tempered glass in many different types of automobiles. It is the standard material used in creating side and rear windows . When an auto accident occurs, these windows will break into smaller pieces for safety.. Most windshields are made from laminated glass, however, which is different.
Tempered Glass Bathroom Shower Doors
Another common application for tempered glass is in bathroom shower doors. Its shatter-resistant properties make it a safe option, especially in homes with small children or pets.
Applications for Laminated Glass
Hurricane Impact Windows
As we previously mentioned, tempered glass is an excellent option for hurricane impact windows. That’s because it is designed to withstand high winds and flying debris that are common during tropical storms. Unlike other forms of hurricane protection, they do not require any setup, teardown, maintenance, or alterations to the appearance of your home.
Automotive Windshields
For safety, in the event of an accident or a rock being kicked up at your windshield from a passing vehicle, most automotive windshields are made from laminated glass. Unlike tempered glass which breaks into smaller pieces, laminated glass holds together.
Another advantage is that laminated glass has less distortion than tempered glass does. This is particularly important for windshields, so you can better see the lines on the road, read signs from a distance and judge the distance between vehicles.
How Laminated Glass Protects Your Home
As mentioned above, hurricane impact windows with laminated glass are designed to resist shattering. This is due to the manufacturing process creating a laminated interlayer that makes it sturdy enough to withstand high winds, flying debris, and impacts, as well as the rapid and extreme air pressure changes hurricanes can cause.
In the event that laminated glass does break, it will hold its shape and stay together. Because it holds a shape, it will still continue to remain in place and provide protection against the elements in the event of severe weather.
Beyond storm activity, laminated glass can also prove a valuable addition for enhancing home security. It is more difficult to break through than regular glass, so it can act as a deterrent for would-be burglars and vandals. If the glass is struck with an object and does not shatter, this may cause someone to move on from your property rather than continuing to attempt breaking and entering.
Get the Best Impact Windows for Your South Florida Home
At Paradise Exteriors, we are proud to serve South Florida as the exclusive installers of the Paradise Platinum Series Windows. In addition to multiple Energy Star Awards for their energy-efficient properties, they are also the only impact windows recognized by the National Crime Prevention Council for helping to take a “bite” out of crime.
To learn more about upgrading your windows to Paradise Platinum, as well as our many financing and warranty options, contact us today to schedule your free estimate.
