Why is my windshield crack spreading so fast

Why is my windshield crack spreading so fast?

Cracked windshields can be more than an eyesore; they’re potentially hazardous when driving your vehicle with cracks in it. Glass is only capable of withstanding so much pressure before weakening or breaking, and large cracks in your windshield could cause sudden changes in pressure that worsen the crack. Thankfully, there are ways you can stop cracks from spreading as rapidly until they can be adequately repaired.

Extreme Temperatures

Glass expands when heated and contracts when chilled, so exposure to extreme temperature changes may cause cracks to widen more rapidly due to the expansion and contraction rates of different portions. Therefore, vehicles should park inside a garage when possible or not face their heater vent directly at their windshields.


Dirt and moisture can enter windshield cracks and worsen their condition, further straining them. A great way to shield it from these elements until you can have the damage professionally fixed is placing a piece of clear tape over any visible cracks in the Glass – this won’t obstruct your view while driving, yet will help keep dirt at bay until professional repairs can be performed on it.

Bumps and Slams

The sudden jarring of your car may also contribute to windshield cracks. Rough roads or accidentally slamming your door may put unnecessary stress on the Glass and force it to move in ways it should not, worsening existing cracks or opening new ones. Be wary when driving on rough surfaces or parking near other cars, as this could further exacerbate existing ones. Park on smoother roads for now until having it professionally repaired.

Drastic Temperature Change

Just like moisture, extreme temperature swings can also contribute to windshield cracking. Exposure to intense heat can cause cracks to spread quickly – to mitigate this, park in the shade when possible and use a defroster slowly on your windshield.

Windshield Cracks

If a rock chip has caused your windshield to develop a long crack, it must be repaired quickly to prevent further spread and make your car pass safety inspection facilities. Some inspection facilities won’t accept your car with cracks in certain places or exceeding a certain size threshold.

RS Auto Glass provides professional and cost-effective windshield chip repair and replacement. Additionally, we can assist you in finding a temporary solution to cracks that have already formed by filling them with cyanoacrylate glue (sometimes called superglue) or applying clear nail polish directly over them. These measures may keep the crack closed until your car can be professionally repaired. Call us today if you suspect your windshield cracking to learn how we can help!