Auto glass damage can happen in the blink of an eye—and in Ontario, it often does. Whether it’s a chipped windshield on the 401 or a shattered sunroof after a storm, knowing the most common causes can help you stay alert and take preventative steps.
At RAM Auto Glass, we repair and replace thousands of windshields, side windows, and sunroofs each year. Here are the most frequent reasons Ontario drivers end up needing auto glass repair—and how you can protect your vehicle.
1. Flying Rocks and Road Debris
This is the #1 reason drivers call us. Loose gravel, salt, or small stones kicked up by trucks or passing vehicles often chip or crack the windshield, especially on highways like the QEW, 407, or 400.
Prevention tip: Maintain distance from trucks and construction vehicles, especially on newly resurfaced roads or during winter sanding.
2. Sudden Temperature Changes
Ontario’s climate is notorious for freeze-thaw cycles. Going from a frigid night to blasting your defroster in the morning can create thermal shock in the glass, especially if it already has a chip.
Prevention tip: Warm your windshield slowly. Avoid pouring hot water on frozen glass or using high heat immediately after a cold start.
3. Slamming Car Doors
When a window or sunroof is slightly damaged, even a hard door slam can send a chip spreading into a full-length crack. The pressure from closing doors with windows up increases cabin air pressure, stressing the glass.
Prevention tip: If you notice a chip, leave a small window gap or close doors gently until it’s repaired.
4. Vandalism or Break-Ins
We see a spike in broken door glass and back windows in parking lots, underground garages, and overnight street parking—especially in cities like Toronto and Mississauga. Thieves often break side windows to grab bags, tools, or electronics.
Prevention tip: Hide valuables, park in well-lit areas, and consider window tinting with safety film for added resistance.
5. Hail and Severe Weather
Ontario sees its fair share of summer storms and winter ice. Hail, falling branches, and frozen debris can easily crack windshields or shatter sunroofs, especially during unexpected storms.
Prevention tip: Use a windshield cover or park under shelter during storm alerts. Stay aware of weather warnings via Environment Canada.
6. Poor Installation or Old Sealant
Glass that wasn’t installed properly—or has aging sealant—can shift under stress or leak. That movement often causes stress cracks, especially near the edges. DIY repairs or cheap glass replacements often result in repeat damage.
Prevention tip: Always use certified technicians, like those at RAM Auto Glass, and get sealant inspected if your windshield was installed more than 5 years ago.
7. Hidden Chips That Go Unnoticed
Some damage starts out microscopic—barely visible to the naked eye. But all it takes is one rough drive, a cold snap, or slamming a door to turn a tiny chip into a major crack.
Prevention tip: If you suspect damage, call for an inspection. Most chip repairs are covered by insurance and can be done in 30 minutes or less with our free mobile service.
Related Reading
- How Weather Affects Auto Glass Cracks in Ontario
- How to Prevent Windshield Cracks From Spreading
- The True Cost of Delaying Auto Glass Repair
Have Damage? We’ll Come to You
Whether it was a rock on the highway or a break-in in your driveway, RAM Auto Glass offers free mobile auto glass repair and replacement across Vaughan, Richmond Hill, Toronto, and the surrounding areas. We work with most insurance companies and back all work with a written warranty.
Call (647) 777-7080 or book online for same-day mobile service.