Automotive technology is amazing, isn’t it? A little more than one hundred years ago, we were riding in buggies pulled by horses. Today, we drive cars that can reach nearly three hundred miles per hour, run on electricity, and slow down if the driver forgets to brake.
Even the glass in a car’s windshield has changed over the years, becoming more advanced. Below, we explain the different types of glass that make up your car’s windshield and windows and why you should care.
Glass Types, Explained
In your car, the glass used for the windshield is different from the glass used for the side and rear windows. Let’s take a look at the different types of glass.
Windshields are made of laminated safety glass. This type of glass is actually made up of a piece of plastic sandwiched between two layers of glass. The three layers are sealed together and any air pockets removed using rollers or vacuum systems. Then, the layers are heated to fully bond them together. The final product is designed not to shatter: instead, it usually cracks into a “spider web” pattern when an impact isn’t enough to break the glass.
This laminated safety glass has to be bent and shaped in a very precise way in order to fit the frame and fully provide structural integrity to the car.
A car’s side windows and rear windshield are made of tempered glass. Tempered glass is extremely strong, much like laminated safety glass, but it differs in a few key ways.
Tempered glass is made by rapidly heating the glass to more than 1,000 degrees Fahrenheit and then rapidly cooling it to room temperature. This process increases the strength of the glass by up to four times. The process also changes the glass so that, if broken, it breaks into small pieces of glass that don’t have extremely sharp edges.
The Evolution of Automotive Glass
A century ago, cars were designed without windshields or windows. Drivers had to wear goggles to make sure that their vision wasn’t hampered by the wind or insects. Soon after, windshields were invented to solve this inconvenience; however, the windshield was made of ordinary glass. You can probably guess why this was a problem!
Early windshield glass shattered just like your windows would if hit with a baseball. That meant that large, very sharp shards of glass were propelled at high speeds toward the driver and passengers in the car. Many injuries were reported, and car manufacturers got to work figuring out a solution.
Enter laminated glass. This type of glass, still used today, is extremely shatter-resistant. Instead of shattering when something hits the windshield, a chip or crack will form in the outer layer of the windshield. Although the windshield sometimes needs to be repaired or replaced, it is still a much more safe, durable, and cost-effective option that ordinary glass.
All that being said, you might wonder why laminated glass isn’t used for every window in your car. After all, debris or even another vehicle can hit the side of your car and shatter the windows.
Tempered glass is often used in side and rear windows precisely because it can shatter. In the event that a car goes into a river, for example, it’s important for the car’s occupants to be able to get out. The car doors might not be able to open, but escape would be possible after breaking the glass. Since laminated glass is nearly shatter-proof, this would make escape impossible. Tempered glass, on the other hand, can be broken into small, dull pieces, allowing the occupants to get out of the car with minimal injury.
We’re Here to Help
Now you know more about your car’s window glass and why it matters! To learn more about your car’s windshield—including what to do if it is chipped or cracked—be sure to check out the previous posts on our blog.
If your windshield is damaged, we can give you your options for repair or replacement. Call us today to get a free quote and on-site service from one of our expert auto glass technicians.