3 Reasons for Cracked Windows

Sometimes it happens overnight: you go to bed and your window is perfectly fine. You wake up the next morning, and see the crack. Cracks come in different shapes and sizes. Sometimes a crack in your window might be one long, thin line running from trim to trim. Sometimes it’s more contained, just a few veins stretching out at the corner of your window.

Neither of these cracks say anything good about the health of your window, or your home. A cracked window can mean a drafty home, or it could spell problems with your window down the line. Some window cracks can be repaired, but often repairs mask the larger problem and if not replaced, the window will eventually break.

But why do windows crack? Sometimes the reasons are obvious. A bad storm or debris can cause windows to crack. Other reasons might not be so obvious but much more common.

Storm Damage

This is the most obvious reason for cracked windows. In the midst of a storm, debris from nearby trees might hit the window, causing it to crack. There may even be hail or sleet storms in which the storm itself could cause the window to crack. Sometimes it’s unavoidable, but you can help decrease the chances of storm damage by trimming nearby trees. Hurricane film and storm shutters can also help to protect your window from cracking during a heavy storm.

Stress Cracks

Not every window cracks because of storm damage, however. Sometimes stress cracks can appear. With warmer temperatures, the window will try to expand, and this can often cause cracks. It’s especially susceptible to stress cracks if part of the window is cooler than the rest and thus resists expanding. This is why stress cracks are most common in windows that are partially covered in shade. These cracks are difficult to prevent, but window panes with greater thermal resistance like high quality vinyl windows can help.

It’s important to keep in mind that stress cracks can occur not just in summer. In winter, when the temperatures drop so drastically that you crank up the heating to make your home more comfortable, stress cracks can still appear.

Pressure Cracks

Pressure cracks are similar to stress cracks in that they seem to appear out of nowhere. They can be created by drastic weather changes, but they can also form when the windows are installed at the wrong elevation level — too high or too low. Pressure cracks typically run all the way across the glass and when you see them, there’s little chance of repairing the window. In most cases, it will need to be replaced. Pressure cracks most often occur in insulated glass windows.

There’s no way to fully prevent cracked windows, but the higher the durability of the window, the less chance it stands of cracking. At Zen Windows, our replacement windows are all immensely durable, crack resistant, and made to withstand the climate in Des Moines. Want more information? Contact us today for a free estimate.