When temperatures can change rapidly to an already weakened area of your windshield and cause it to expand or fluctuate to such a degree that an additional or more profound defect occurs along the defect’s most vulnerable edges.
If you have any small windshield dings or edge cracks, get them filled immediately! As the weather drops your windshield must deal with the “thermal stress” of a warm interior and a cold exterior. A small ding can turn into a very expensive, spreading crack.
Think of the sound that you hear when you pour a warm liquid over ice. The popping sound is thermal shock applied to the ice. Rapid changes in temperatures will cause certain materials to chip, crack, or spread most every time.
It doesn’t take liquid to rapidly change the temperature causing windshield to break. Any time that the interior and exterior vary drastically in temperatures, thermal shock will most likely affect windshield chips and cracks. In fact, the closer the damage gets to the edge of the windshield, the greater the chances of the damage propagating into a crack. If it is 90 degrees outside, your vehicle interior can reach staggering temperatures in just minutes.
Your windshield is made up of 2 pieces of glass “squeezed” together under heat and pressure. The two are separated by a thin sheet of safety material. When the interior reached 120+ degrees, the piece of glass on the inside expands. The outside is still hanging in there at 90 degrees and remains the same shape; however, the expanding piece on the inside most often times will cause failure to the windshield at any impact point that exists on the exterior. An opposite example is when the hot car is then cooled down with an air conditioner. The interior glass begins to contract, pulling on the outside piece of glass causing failure.
When your windshield is compromised by a flying rock or other debris, you need to go to a licensed, quality windshield repair technician as soon as possible for windshield crack repair. If you cannot quickly make it to a repair shop, follow these steps to increase the chances of saving it:
– Try to keep the interior and exterior of the vehicle balanced in temperature. Turn off you’re a/c or heater and crack all of the windows about 1”. Open your sunroof if you have one.
– Park it in the shade and leave the windows cracked. Do not place a sun shade in the window.
– Do not wash the vehicle and do not clean the area or use your washer fluid on the windshield.
– Place clear tape over the damage immediately. Any kind of tape will work…scotch tape, packing tape, etc.
Thermal shock is to blame for that little, tiny chip turning into a long crack. Make sure that you stay away from costly replacements by getting your windshield repaired quickly before thermal shock costs you money.
Pitstop Autoglass + Windshield Repair Service Center® is always ready to repair your windshield and get you back on the road safely.
If you have any further questions, stop by your local Pitstop for a no-cost evaluation.
For more technical information about Thermal Shock, visit wikipedia here: