By Andy Jensen on April 13, 2021 in Life Hacks
Few car ownership experiences prove more aggravating than finding a giant crack in your windshield. It’s understandable when it happens by rock strike, but super annoying when it mysteriously appears overnight. Here’s a look at the science behind windshield engineering, and how you can help prevent expensive damage.
Why Do We Have Windshields?
You may be muttering this question to yourself if you just got a crack. Unfortunately, you can’t just rip your windshield out of your vehicle and drive around like you’re in a scene from the Beverly Hillbillies. For one, a ton of bugs would hit you in the face. And two, the windshield is a necessary part of your ride. In relatively modern cars, a windshield acts as a part of the chassis. This means a windshield serves as an integral part of a vehicle’s crash structure and doing without one is the equivalent of cutting your doors off. In an accident, a windshield transfers crash energy around the cabin, promotes proper airbag deployment, and prevents objects from ejecting from the car. If yours is cracked or otherwise damaged, you need to replace it.
How Did My Windshield Get Damaged?
A surprising amount of hazards want to use your windshield as a punching bag. Here’s what to watch out for.
- Dirt
You think it’s just annoying road dust, but dirt is really abrasive at the microscopic level. While the damage is tiny, it adds up over time. Keep your windshield clean to protect it.
- Worn out wipers
We’re all guilty of occasionally forgetting to change the wipers on time. Old wipers — especially damaged ones — can cause the wiper arm to scratch the glass. Change your wipers on time, about every 6 to 12 months.
- Harsh chemicals or tools
When you’re running late, it’s cold out, and a sheet of ice covers your windshield, it’s easy to get impatient. However, chipping away at the ice — and inevitably chipping away at the glass — or dousing your windshield in acidic vinegar can cause damage over time.
- Extreme temps
While high temps won’t crack your windshield, heat expands windshields slightly, eventually turning tiny, unnoticeable cracks into a huge problem.
- Road debris
Gravel, rocks, asphalt, and ice chunks can be kicked up by other vehicles, smashing into your glass.
- Accidents
Fender benders damage more than just the fenders. If you are involved in a collision, the windshield could be damaged as easily as the bumpers are.
How to Prevent Windshield Damage
While drivers encounter plenty of threats to their windshields, they can prevent damage with the following methods.
- Take the road less traveled
It’s not just a good saying for an inspirational Facebook post. Choosing quieter routes lessens the chance of rocks and debris smacking your windshield.
- Drive slower
A lower velocity reduces the impact forces, meaning rock strikes are less likely to cause damage. It’s science!
- Avoid gravel roads
Your paint will thank you for this one too.
- Park in a garage at night, if possible
Protecting your car from the elements prevents hail damage and snow and ice buildup. And when it’s time to sell, you can include “Garage kept!” in the ad as a bonus.
- Park in the shade on hot days
Yes, choosing a shady spot keeps the interior cooler. It also prevents high temps from expanding any existing tiny cracks.
- Go easy on the scraper
Ice scrapers can chip the glass if you’re too aggressive or use them to tap the ice. Use the defroster and gently remove ice with a scraper or brush.
- Don’t follow construction vehicles
Ever notice how dump trucks have that “stay back 200 feet” warning? That’s because gravel and cement can spill out, bounce off the road and damage your vehicle. Staying back more than 200 feet lets the debris settle on the road by the time you pass over it.

How Do Windshield Coatings Work?
If you want to be a little more proactive about damage prevention, consider windshield films and coatings.
- Windshield film is similar to window tint, except it goes on the outside of your windshield. This clear plastic cover — which protects your ride from small cracks and debris — is nearly invisible once applied. Bonus: Even clear windshield tint reflects UV rays.
- Windshield coatings contain a mixture of chemicals that provide a tough, invisible outer shell to ward off minor debris. Note: Leave installation to the pros and know that these coatings typically wear off after a year or two.
Too late? What to Do with a Damaged Windshield
If you find a ding or crack in your windshield, consider these steps to minimize the damage and potentially lower your repair bill.
- Call your favorite insurance company.
If you have a costly windshield and your deductible is low, you may be reimbursed for some of the cost.
- Also, call your local glass pro right away to schedule an appointment.
A ding or chip can often be repaired without removing the windshield, sometimes in as little as five minutes. Keep driving though, and that chip will become a crack, requiring full replacement.
- Delay car washes, even if you hand wash.
The water pressure or cold temperature could make the crack worse.
- Drive gently, or just minimize driving if you can
This will prevent road vibrations from making the crack worse.
- Avoid extreme temp changes
Subjecting a damaged windshield to noticeable changes in temperature can quickly make matters worse.
Conclusion
Stressed about breaking that big chunk of glass on your ride? Don’t be. With proper maintenance and some attentive driving, you ward off damage. If not, windshield damage can usually be repaired quickly and easily.