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Why Windshields Crack And How To Fix Them

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As a car owner, you may dread seeing a small crack in your windshield. While it may stay small in size, chances are that it will continue to grow and require windshield replacement services. Here are some reasons why windshields crack, as well as how you can fix them.

Causes of Cracked Windshields


The most common reason that windshields can crack is due to the high velocity impact of a stone. This can easily happen as you are driving down the freeway at high speeds. Stones may get kicked up from the road by a car in front of you, or one may fall off an overpass and land directly on your windshield.

The damage can start small, but that small damage can end up growing into a large crack that spreads across the entire length of your windshield, if you do not have it repaired.

Temperature Variations

Sometimes, the cause of a crack is not in your control at all. Incredibly cold and hot temperatures can cause a windshield to crack due to  environmental stress. This can be done by leaving your car outside on a hot summer day or having it exposed to subzero temperatures during a winter vortex.

Stress on the glass is a reason why it is advised not to clear ice off your windshield with hot water. The temperature difference can shock the glass and cause a crack to develop due to the sudden temperature change.

Fixes For Cracked Windshields

Resin Repair

A popular method to repair windshield damage is a repair kit. These can be purchased at an auto parts store and used on your own at home. It involves removing all air from the crack and applying a resin to the surface. It fills the crack and seals it, which will prevent the crack from getting bigger, due to water and dirt getting inside it and making the glass weak.

Resin can be used to fill large cracks as well, though it will require professional help to do it.


If you ignore a crack for too long, it will get to the point where it is too big to fix on your own. You'll need to have the windshield removed and replaced with an entirely new piece of glass. This ensures that the new glass going into the car will be strong and not continue to break due to the stress of driving a car and having the glass vibrate as you travel down the road.