Q: What Material Are Windshields Made From?

Windshields have been utilized to protect occupants who drive and ride in the vehicle from wind and debris including insects, dust, and rocks. The windshield also provides a valuable service by creating an aerodynamic wedge that plows through air, reducing vehicle drag and improving fuel economy. Since the early days of the Model-T, the windshield has evolved – especially in regards to the materials it is manufactured with today.

The windshields on today’s modern cars, trucks, and SUVs are made out of laminated safety glass. The glass is comprised of multiple layers of glass that is infused with UV-A and UV-B coating to protect the driver from ultraviolet rays. The glass itself is extremely difficult to shatter, which was the intent of the designers who developed automotive safety glass. If the glass is hit with a large, hard object, the glass will break into very small particles that will hold together; as opposed to breaking in larger pieces comprised of sharper edges.

The glass has a polycarbonate inner layer that helps bond broken glass particles together in the event of a collision. This design has prevented millions of injuries and allows the driver to safely stop their vehicle after being hit without their vision being compromised by broken glass shards. When a windshield cracks, the outer layer of safety glass is what is broken. This is why a glass crack can be repaired on the outside of the vehicle if it is small enough. To repair these small cracks, an epoxy resin is applied into the crack and fills the crack, forming a translucent and virtually unnoticeable finish.

While it is still possible to drive with a cracked windshield, you should have it replaced as soon as possible because it poses a safety hazard if your car is involved in a front-end collision. Not only is this a safety concern, but there are also cracked windshield regulations that each state follows.

The windshield rules and regulations vary depending on the state in which you live and the vehicle is registered. Not only are these rules intended to help protect the drivers and occupants of the vehicle, but they are also a part of some states’ registration process. In several states, when you have the vehicle emissions tested, they will also include a safety inspection. When you have a cracked windshield, the vehicle is automatically failed and you won’t be able to register the vehicle. A cracked windshield can also cause the police to pull you over and issue you a citation also known as a fix-it-ticket.