The side windows and rear windshield of a car are made of tempered glass. Tempered glass is extremely strong, like laminated safety glass, but it differs in a few key ways. Tempered glass is manufactured by rapidly heating glass to more than 1000 degrees Fahrenheit and then rapidly cooling it to room temperature. There are two main types of glass used when building cars.
Vehicles that circulate today have laminated glass or tempered glass. Automatic glass is tempered or laminated. The glass generally used for the rear window and the front and rear door windows are made of tempered glass, while the windshield is made of laminated glass. A car is made up of many glass exteriors.
While side windows, rear windows and windshields are essential on all vehicles, certain additional glass accessories, such as sunroofs, are also available on modern car models. Made of sand, limestone and soda ash, all glass is typically designed to be 100% recyclable, sustainable and non-toxic. These criteria have become vital, as they help preserve the environment and ensure that a carbon footprint is not left behind. The glass generally used for the front and rear door windows and the rear window are made of tempered glass, the windshield is made of laminated glass.
In addition to laminated glass, automakers began using tempered glass in the late 1930s. This type of glass is used in the side and rear windows of the vehicle and gains strength through a rapid heating and cooling process that strengthens the outer surface of the glass and its core. This “tempering process” makes glass many times stronger than untempered glass of the same thickness. Glass and PVB sheets were heat fused and laminated safety glass was born.
Different types of glass are used throughout the vehicle because each type of glass has a different purpose. And in severe impact situations, the glass “breaks”, but usually doesn't separate because broken glass pieces usually stick to the vinyl inner liner. Current laminated glass consists of a thin layer of polyvinyl butyral (PVB) sandwiched between two layers of solid glass. Because of this, automotive glass is manufactured in two different types of safety glass to protect both the vehicle structure and the occupants inside.
Glass manufacturers continue to explore new ideas to make glass stronger, safer and more adaptable to new vehicles. In addition, laminated glass can be repaired, but tempered glass breaks completely in an accident and requires a complete replacement. The second type of aftermarket automotive glass comes from the OEM, but was created on a different production line. The glass used in the windshield of your car is very different from the glass used in the windows of your house.
The reason for the popularity of glass in automotive parts is the strength, durability, flexibility and versatility they have to offer. That inserted layer of PVB is what allows the glass to absorb energy during an impact and gives it resistance to the penetration of flying projectiles. Glass, in this case, is used to refer to the side windows, the deflector glass, the ventilation glass and the glazed roof (if the car has one). Tempered glass is created by rapidly heating and then cooling the glass to room temperature by introducing it through a blower system.