Request a Quote

How the Sun Damages Your Windscreen


As a sunshine country (also dubbed sunburn), Australia is susceptible to extreme heat year-round. With this sweltering heat comes the likelihood of us experiencing sun damage. Not just to ourselves but also to our cars. Yes, our cars are susceptible to the sun too! However, unlike us, cars can’t be protected by a long-sleeved shirt and SPF 50+, so we need to take other measures in protecting our vehicles. In addition, with the unfortunate effects of global warming, The Bureau of Meteorology’s State of Climate 2020 report Australia’s temperatures continues to change. Therefore, we can expect to see hotter days in the near future. With these facts known, it’s even more important to know the dangers of the sun on ourselves and our cars.

Our cars are an investment, and learning how to avoid sun damage can preserve your car’s value, your safety and reduce the number of repairs your car may require. Of course, we’re probably all aware of how the sun’s ultraviolet (UV) rays oxidise and fade car paint. Resulting in our cars looking a little worse for wear. But too much sun exposure also affects your

windscreen and almost every part of your car. So today, we tackle how sun damage puts a strain on our windscreen, and of course what we can do to combat this.

How Does the Sun Damage Car Windscreens?

Whilst not noticeable at first, sun damage accumulates slowly and becomes evident after a few years. Prolonged and constant exposure to the unforgiving Australian sun can cause extensive damage to almost all parts of your car, including the most vital parts of your vehicle – like the windscreen. Unless you have invested in professionally installed window film to protect your vehicle, you’ll reap the repercussions. If untreated, the sun can even break your windscreen, which will require more than just a glass repair.

Watch Out for Temperature Changes

But how does the damage happen? The biggest culprit to windscreen damage isn’t necessarily the sun but the fluctuation of temperatures inside the car. For your glass to break, it doesn’t take much. The temperatures inside cars are hotter than the temperature outside. For example, during an Australian summer, it can easily hit 30 degrees by 9 am. However, it only takes ten minutes for the inside of your car to reach 44 degrees. 20 minutes of sun can increase that temperature to 60 degrees! This is why you’ll see messages either online or on the news about the risks of leaving your children or pets unattended in a locked car.

Extreme Temperature Changes Cause Stress Cracks

Cars left outside become a mobile sauna that houses a battle between two temperature extremes. It’s a battle of the interior and exterior. Once some heat has accumulated, the windscreen glass expands. When we turn on our AC to avoid melting like an icy pole, the sudden cooling of temperature causes the glass to rapidly shrink. This face-off between hot and cool temperatures applies pressure on your windscreen, causing cracks or splits to develop.

As windscreen cracks tend to spread, any existing damage worsens, as the conflict between temperatures causes existing damage to expand. This often goes unnoticed, as most of us assume the damage to our windscreens come from gravel. However, the sun is the silent culprit causing windscreen damage known as “stress cracks”. Unlike cracks and chips that happen under impact from debris or hail, stress cracks pop up out of nowhere. So if you notice an unexplained crack that suddenly appeared, it could be caused by the sudden change in temperatures.

What Are Stress Cracks?

This might come as a surprise, but stress cracks can happen even after just one single impact of sunlight. Now we don’t mean to scare you from driving during the daylight, but this is important to know when it comes to your visibility. And it’s something that’s not talked about enough in the realm of car safety.

Under the sun, your car’s glass and metal components will heat up. Since the metal naturally heats faster, this causes stress on the middle of the glass, which creates cracking. Usually, these cracks occur on the edges of windscreens but can spread out onto the entire windscreen.
How Can You Avoid Windscreen Stress Cracks?

The good news in all of this is protecting your car against sun damage is manageable. Some strategies you can implement include:

1. Park in the shade

Simply parking your car in the garage, basement, and undercover is an excellent way of safeguarding your windscreen. We know this isn’t always available, though. To get around this, you’ll want to cover your car to avoid direct sunlight. Particularly if your windscreen already has existing chips or cracks that are yet to be repaired. Purchasing accessories like a windscreen sunshade will also help reduce the heat inside your car, which means fewer chances of stress cracks, as well as your interior suffering from UV damage.


2. Let your car gradually cool down

We understand the temptation (dare we say second nature) of blasting your AC as soon as you enter your car on a sweltering summer’s day. Yet this is one of the worst things you can do to prevent stress cracks. So instead, get into the habit of turning on your air-con if your car’s cooling system is too low at first.

3. Let your car gradually warm-up

Similarly, when winter makes its way back around, you’ll want to gradually heat your car instead of hitting your interior with the defroster. It may require a little more time and preparation, but ultimately it will save your windscreen from potentially cracking as well as a repair bill. You’ll also want to avoid pouring boiling water to warm up the windscreen, as the sudden temperature change is also likely to cause the windscreen glass to expand and cause windscreen damage.

4. Tint your windows

Window tinting is more than just for privacy. It also is another solution in protecting both your car’s interior and exterior from UV damage and potential stress cracks. Implementing these tips will also prevent your interior from being damaged too! Say goodbye to hot steering feels and faded upholstery.


Why You Shouldn’t Delay Repairing a Damaged Windscreen

If you believe your windscreen has become damaged due to a temperature fluctuation, it’s best not to delay. No matter how small and harmless you think, it may be. Instead, seek help from a reputable professional. You won’t want to postpone repairs for a couple of reasons.

If on the driver’s side, cracks serve as a severe hindrance to your visibility. Poor visibility can increase the risk of a crash by 30%. With our visibility decreased, we can’t accurately determine when and how much to slow down by. A damaged windscreen also puts you at risk for more significant injury. When your windscreen requires a repair, your roof is extra susceptible to caving in during an accident, which is less than ideal.

The same goes for your windscreen being the first line of defence in a front-on collision, but it also impacts your airbags ability to deploy as well! Your windscreen truly does impact multiple aspects of your safety, which is why a delay in repair is never recommended. Your safety heavily relies on the health of your windscreen.

Seek Your Repair Sooner Than Later

If you pledge to frequently inspect your windscreen, employ a sunshade to your rescue and gradually cool or heat your car, you can undoubtedly expect fewer stress cracks. As harsh as the sun is, we have multiple solutions to combating sun damage in today’s age. If you notice a crack, don’t put your safety on the line, even if it seems insignificant. Book a service or repair today by calling Novus on 13 22 34. As the trusted experts in windscreens, we feel confident in our services and our ability to provide you with the utmost care.

Skip to content