Does the windshield in your car fog up every time when the outside temperatures are low or when it’s raining? Covering all glass surfaces inside the car, this thin layer won’t go away even with the ventilation turned on. Not only is this annoying, but it also obstructs visibility and affects overall safety. Although we know this happens when the moisture is high, tracking down the source of this problem may be tricky. In this article, we will explain why glasses inside the car fog up and how to prevent it.  

Dirty cabin filter

Most modern cars have a cabin filter, which removes various contaminants from the air that go towards the passenger compartment. These contaminants range from dirt and dust to soot and allergens. As the time and miles go by, this filter fills up with layers of dust and dirt deposits. Not only does this obstruct the air flow, but it also keeps the moisture inside it. As a result, the air that goes into the cabin through the ventilation system will be dirty and damp. This moisture will condensate on the windshield and door glasses, which we will see as a thin foggy layer.

Moisture inside vehicle

Another likely scenario is that larger quantities of water and moisture found a way to get inside the car itself. The easiest way to spot this is by checking if the floor carpets and the sound insulation beneath it are wet. This is a definite sign that rain and water from the road are getting into the car. In many cases, a cause for this can be something as simple as clogged scuttle or sunroof drains. With the proper path blocked, the rainwater may get inside the car during heavy downpours. Also, damaged or worn weather seals at one or more doors can have an identical effect in certain situations. As a last step, a detailed check from underneath may reveal a corrosion that created holes in the floor.

What can I do to prevent this?

Start by replacing the cabin filter once a year, as this will ensure a stream of clean and dry air. Another preventive step involves cleaning all drains, so that the rainwater wouldn’t get inside the car through the ventilation. Also, applying a layer of protective coating on all weather seals will make them flexible and ensure they last longer. And make sure not to step on them when entering the car, as this can cause mechanical wear and damage. In the end, give the car a thorough wash and repair any traces of corrosion.

How important is this service?

As we have explained in this article, finding out why windows in your car fog up isn’t too complicated. However, if you don’t have the right tools or don’t feel up to the job, consider hiring a professional. At FixMyCar, we have certified and seasoned technicians that can come to your home and solve all issues with fogging-up. This will ensure that all important components are checked and your car is ready to hit the road.