Parked in the sun? Here’s how to keep your windshield safe and cool

When the summer sun is blazing, parking your vehicle outside can do more than just overheat the cabin—it can also cause serious wear and tear on your windshield. While it might seem like just a piece of glass, your windshield is a key safety component of your vehicle, and the intense heat of a parked car in full sunlight can put it at risk.

If you’ve ever returned to your car after a long day under the sun and noticed tiny chips or even a growing crack, you’re not alone. 

Let's explore practical ways to keep your windshield safe and cool when parked under the summer sun.

Why is direct sunlight hard on your windshield?

Your windshield endures a lot—wind, debris, fluctuating temperatures—but one of the most damaging conditions is consistent exposure to direct sunlight. The glass can expand in extreme heat, and if there’s even a minor chip or flaw, that heat can cause it to grow into a larger crack. This happens because glass, like most materials, expands when heated and contracts when it cools. Sudden changes in temperature (such as blasting the air conditioning once you're back in the car) can worsen the stress on the glass.

Use a windshield sunshade

One of the simplest and most effective ways to protect your windshield is by using a reflective sunshade. These foldable accessories block UV rays, reduce interior temperature, and shield your dashboard and windshield from direct sunlight. A good-quality sunshade can make a noticeable difference in how hot your car feels and helps prevent your windshield from overheating.

Park in the shade whenever possible

This may seem obvious, but actively choosing a shaded spot—whether under a tree, in a garage, or beside a tall building—can save you from heat-related windshield damage. Even partial shade can reduce the temperature on the surface of the glass, lowering the risk of cracks forming or worsening.

If you frequently park in the same area, consider investing in a carport or portable canopy for added protection.

Crack the windows slightly

While you shouldn’t leave your windows open wide, cracking them slightly (no more than a centimetre) can allow hot air to escape and prevent pressure from building inside your vehicle. Excess heat and pressure inside a closed car can intensify the strain on the windshield, especially if there's an existing chip.

This small action can help moderate the temperature and reduce the risk of stress-related damage.

Avoid sudden blasts of cold air

After your car’s been sitting in the sun, you might be tempted to immediately crank up the air conditioning. However, doing so sends a cold rush of air directly onto the hot glass, which can cause it to crack due to thermal shock.

Instead, allow your vehicle to ventilate for a minute before turning on the AC. Then, direct the airflow toward your feet rather than the windshield until the interior temperature starts to level out.

Stay on top of small chips or cracks

Even the smallest imperfection in your windshield can expand in the heat. If you notice a tiny chip, it’s better to deal with it right away before it becomes a more serious issue that requires full replacement.

We offer professional windshield repair in Toronto drivers can count on to prevent small damage from becoming a costly problem. Quick action saves both time and money.

Know when replacement is the best option

If your windshield already has visible cracks or significant damage, especially near the edges, summer heat can accelerate the problem. In such cases, the safest move is to replace the windshield entirely. Our team at National Auto Glass provides reliable windshield replacement in Toronto residents trust to get them back on the road safely.

Book your appointment today

Protecting your windshield from heat damage isn't just about comfort—it’s also about maintaining safety. If you’ve spotted a chip or think it might be time for a replacement, don't wait for the next hot day to make things worse.

Call us today at (416) 666-7345 or book your appointment . We’ll assess the damage and recommend the best solution to keep you safe, whether it's a simple repair or full replacement.

Summer should be stress-free. Let us help you keep your windshield in top shape all season long.