While you may never get in an accident, damage to your vehicle’s glass is almost inevitable. The windows in your car aren’t all the same, and they do more than just let you see out while protecting the cabin from wind and weather. How does glass function in your car, and how can it be repaired?
Not All Auto Glass is the Same
There are two types of glass used in automobiles: laminated and tempered.
Laminated glass is made from a layer of plastic sandwiched between two pieces of glass. These three pieces are heat treated to create a single uniform sheet with the plastic layer acting as a shock absorber. If the glass breaks, the plastic keeps the pieces together so shards don’t end up flying around the cab. This glass is used for the windshield, and in some vehicles, the rear and side windows. Laminated glass is extremely strong and is used as a structural component: the windshield alone accounts for almost half of your vehicle’s structural integrity in front impacts and over 60% in rollovers.
Tempered glass is made by taking a normal sheet of glass and repeatedly heating and cooling it. Uneven cooling causes the center of the glass to pull away from the edges, creating tension. This nearly quadruples the glass’s strength, but if anything interrupts this tension, the entire sheet shatters into small pieces. This is desirable in automotive use because it creates small, rounded chunks that are far safer than the jagged edges that can be left by standard glass. Tempered glass is used in side and rear windows.
Both laminated and tempered glass can be repaired, although impacts that laminated glass would shrug off will often be enough to cause tempered glass to shatter. Fortunately, most glass damage is experienced by the windshield since it faces oncoming road debris.
Legal Issues with Damaged Glass
While damage may not be enough to break the glass, it’s illegal in most states if it poses a visibility or safety hazard. In Wisconsin, you could be ticketed if your windshield has any of these issues:
- Cracks directly in front of the driver or obscure the driver’s vision
- Cracks that extend more than 8 inches from the edge of the windshield
- Chips and stone damage more than a half inch wide in front of the driver or more than one-and-a-half inches wide anywhere on the windshield
- Any abrasions or etching that obscure the driver’s view or are directly in front of the driver.
Can My Car’s Glass Be Fixed?
Chips can be repaired if they’re smaller than one and a quarter inches, while cracks are not typically repairable. If the damage extends to the edge of the windshield, it can compromise the glass strength and the seal between the glass and the body, no matter how small it may be. The repair will still leave visible damage, so it’s generally a good idea to replace glass if the damage is within your field of view.
How is Automotive Glass Repaired?
Repair begins by thoroughly cleaning the area to remove any debris using glass cleaners and clays. Scratches are repaired using a series of specialized polishes that are hard enough to remove glass while fine enough to leave a clear finish.
To repair chips and cracks, the technician uses an applicator with a pressurized cup to push a plastic resin into the damaged area. A UV light is shined on the repair, completely curing the plastic. This bonds together the glass and plastic layers, returning structural rigidity. Finally, the repaired area is polished to restore transparency.
Where’s the Best Place to Get My Car’s Glass Repaired?
When you need your vehicle’s glass repaired or replaced, visit Merton Auto Body. We’re an I-Car Gold Class Certified auto body shop with the technicians and equipment to get your car looking and performing like new. Need to get an insurance estimate? We have an appraiser on staff so you can get your repair approved quickly.