You’ve likely been there. You jump right into your vehicle and also after you’ve been driving for a couple of minutes, your windows start fogging up. Why go this happen and what can you do about it?

Why carry out Windshields Fog?

There are a variety of reasons why her windshield would certainly fog including:


Humidity causes a buildup in water the turns right into water vapor. You breathe the humid air. This wait comes out from inside her body or turn off of it. Windshield fogging often tends to be much more of a difficulty when over there is an ext than one human being in the auto since over there is more breathing.

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Temperature is actually molecules moving. More moisture is hosted with heat air than cold. However, this isn’t a chemical reaction. The molecule aren’t stop on come water molecules. More water i do not care gas once it’s warmer than it walk a liquid. And, there’s more space between each molecule with warmth air therefore, the water molecules deserve to fit right into this space.

Surface Tension

Tiny droplets form from water due to the fact that water molecules choose other water molecules as opposed to something prefer glass.


Moist, heat air condensing when it hits your car’s chillier windshield causes condensation. This normally happens in the beforehand morning. This is additionally why top top humid, warmth days when you have actually your auto air conditioner to run you’ll view condensation form at the windshield’s base where it meets the cool air.

When there’s 100 percent relative humidity, if the temperature to reduce more, the water needs to discover its way out someplace. Top top a morning that’s cool external when there’s fog or dew ~ above the ground, that’s due to the fact that the moist, warmth air contacts the cold ground.

How to Clear away the Fog on her Windshield

You have the right to clear fog in countless ways. And also although there’s no special way of law it the works finest each time, the two that are much more likely come work better are together follows.

Dry the wait Out

Your ideal option is to operation your wait conditioner, depending upon your lull level. This method works well once the exterior temperatures are over freezing and damp, wet humans acquiring into the vehicle causes the fog. If cold is ideal when running your A/C, you can still operation the air in ~ a warmer temperature and also get rid that the fog.

Evaporate the Water Vapor

For straightforward and rapid fix, rotate the warmth on and also run it v your defrosters. This causes the condensation to evaporate type of favor the moisture on your apparel evaporating as soon as you revolve the clothes dryer on. This technique works much better when over there are chillier temperatures and you are capturing the fog buildup early.

When her windshield is extremely foggy, you can use a little squeegee or dry towel to settle the fog quickly and also then rotate on the cold A/C. Progressively increase the air’s temperature if you uncover the A/C is too cold because that you until you dry out the wait inside her car.

Let’s conveniently go over some things you have the right to do to eliminate the fog from your windshield:

Put her defroster ~ above a high setting.Set the temperature to hot.Turn turn off the recirculation setting.Turn top top the wait conditioner.Crack your windows.

Keep in mental that as soon as you’re dry air that’s inside her vehicle, you have to pull in the outdoors air fairly than simply circulating inside air. This days, many defrosters currently do this.

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Now, that you know what come do as soon as your automobile windshield fogs, do you understand what to execute if her windshield has a chip or a crack? contact Anthony Volk Auto Glass today at (610) 436-9727. Ours team is was standing by because that all your auto glass needs!

Our very trained technicians know how to prevent the windshield chip or cracked from spreading into a bigger concern that might end up costing you much more money.

Anthony Volk is a 3rd generation auto glass installer born and raised in West Chester, PA. With over two decades of personal auto glass experience he and his team will carry that endure to you.