How to Defrost a Windshield : Definitive and Comprehensive Guide

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How to Defrost a Windshield

Let’s face it; we’ve all been there sitting on the driver’s seat, holding the steering wheel, and struggling to see the road. Driving with a frosted windshield and foggy windows is daunting, and it can be fatal during the night.

Modern cars have smart features to defog the glass, so you are no longer required to manually rub off the windshield with a cloth.

But how to defrost a windshield is something everyone is not aware of.

Well, this post rounds up the quickest tried-and-tested ways to clear the frost within minutes and drive safely to your destination.

From defrosting in summers to rains, and winters these tips will surely help you get better visibility of the road while reducing the hazards of accidents.

How to Defog Windshield: How to Defrost a Windshield Fast

Running out of time and want to reach your office before it gets too late? Here are some quick tips to clear the fog, on the go.

Turn the Air Recirculation Off

How to Defog a Windshield

The air inside your car is causing the fog to build up even more as you turn on the air conditioner with air recirculation on.

Instead, turn off the air recirculation and let the outside air come inside the car. Colder air is dry and absorbs moisture, which helps in defrosting a windshield.

It would be great to turn the fan speed to 2 or 3 settings for a better flow of air.

Turn the Heater On

Hot air eats up the moisture, so cranking the heater will help. However, using the heater for too long isn’t great as hot air holds moisture, so the fog will build up again.

Use the AC

Once the heater has done its job, turn it off and turn on the AC. The cold air from the AC helps in absorbing the hot air inside the car to remove the moisture.

Roll the Windows Down

How to Defrost Windshield Fast

This will help you match the car’s temperature with the outside temperature for quicker results. Yes, you may feel the outside cold, but it helps in clearing the fog.

Once the fog is clear, roll the windows up and drive safely.

Also Read: 25 Best Car Essentials for Winter

Why Does Frost Form on Car Windshields? And Why Should You Worry About It?

Frost starts developing on your car windshields when the temperature inside the vehicle is higher than the outside temperature.

Frost Forming on Car Windshields

As hot air holds moisture, so when it touches the cold glass, condensation happens as you see a milky white layer on the screen.

In summers and rainy days, the frost builds up on the outside of the windshield, as the temperature inside the car is colder than the outside temperature.

Frost build-up is common, and almost every car driver has to deal with it at some point. However, you should never hit the road with your vehicle without defrosting the windscreen.

Failing to defrost the windshield can lead to an accident, poor visibility being the top reason. Furthermore, the headlight from an oncoming vehicle can refract into the driver’s eyes, making it challenging to drive during the night.

Moreover, driving with frost or ice on the windscreen or car’s windows can attract heavy fines up to $1000 in some states of the U.S.

Follow these tips to defrost the windshield glass quickly, and drive wherever you want.

Defrost the Windshield and Rear Screen of Your Car with these Scientific Tips

Here I’ve covered the easiest hacks to clear the car’s glass from frost in summers, rains, and winters. This post will help you get rid of poor visibility irrespective of the weather.

How to Defrost a Windshield in Winter?

How to Defrost Windshield in Winter

Defrosting a windshield is hardest during the cold weather, especially if it snows in your area. Start with scraping off the snow gently so that the below-mentioned tips work effectively.

If there is no snow, hop inside your car, and use these hacks to clear the fog.

Recirculate the Air

How to Defrost Windshield in Winter

The air inside the vehicle is hot, and when it touches the glass, it condenses and results in frost. Tap on the “Fresh Air Mode” located on the dashboard just below or aside the recirculation button.

It lets the cold air flow inside the vehicle to balance the temperature. This hack takes some time to clear the fog, so be patient and enjoy listening to your favorite music tracks while the process goes on.

Decrease the AC Temperature

This tip requires you to wear the fluffiest and hottest of jackets and overcoats. If you are in a rush, turn the AC on, and let it cool the cabin.

When the inner temperature matches the outer temperature, the fog will fade away automatically.

Once done, turn the AC off, and drive your car with the recirculation off and normal fan speed.

Use the Defrost Vents

How to Defog Windshield

Modern automobiles come equipped with a defrost feature that regulates the flow of air towards the front as well as the rear screen. Look for this button in your car; it has three or four squiggly arrows pointing in an upward direction.

Press it, and wait for the magic to happen. Defrosting is extremely helpful in areas with extremely cold temperatures and snow.

You can drive your car with the defrost mode on, and it will keep the frost from coming again.

Use Some Kitty Litter

Fresh Step Advanced Cat Litter

It may be a little surprising, but using kitty litter can help in defrosting the windshield. Put some Fresh Step Advanced Cat Litter inside a cotton sock, and toss it on the dashboard near the defrost vents.

The litter will absorb the moisture from the air, and you won’t see frost on the windshield.

Use the Heater Intermittently

Using the heater constantly can result in fog forming on the windshield. So you should avoid using the heater for a longer time.

Use the heater intermittently, and turn it off once you feel warm and cozy. Hot air holds more moisture, so the fog can show up again, which may cause trouble while driving.

A Pro Tip: It would be great to invest in good winter wiper blades as they are designed to remove snow effectively. Replace the blades with the winter blades, and clean the windshield quickly.

How to Defrost a Windshield Without Heat?

Using hot water can damage the windshield, and you may end up spending money on fixing the cracked windshield. As per car experts, you should never use a hot liquid on a cooled glass surface, as it is not the safest practice!

Risks of using Hot Water on a Frozen Windscreen

Pouring hot water on the windshield seems to be the best solution when you are late for work and worried about dropping the kids at the school!

However, you may see cracks developing on the glass right after you pour water on the frozen windshield.

Here’s why you should never use hot water for defrosting glass:

Cracked Windscreen

How to Defrost a Windshield Without Heat

When you spray boiling water on the cool glass, there is a sudden change in temperature. The glass expands quickly and then contracts, which leads to cracking.

In some cases, the entire windshield gets shattered, and you may leave the house with a hefty repair bill.

Scalding and Steam Burns

Apart from the windscreen issues, pouring hot water isn’t good for you as well. The water may bounce off on you, and it can be excruciatingly painful. When the water hits the ice, it forms steam, which can cause steam burns on the hands.

Damaged Paintwork

Damage Caused by Using Hot Water on a Frozen Windscreen

The hot water rolling down the windshield can ruin the paint job of the glass surrounds and the bonnet. There’s a thin layer of protection on the paint, and it gets deteriorated when washed off with hot water.

Quick Hacks to Defrost a Windshield Quickly Without Heat

So how do I clear the fog without heat? Here’s how to defrost car windows without heat:

Scrape Off the Snow

Scrape Off the Snow with Ice Scraper

You cannot clean the frost without clearing the snow deposited on the windshield. I prefer using ice scrapers and snow brushes, as they work well and do the job quickly.

However, some of my friends use wipers to flick off the snow. Unfortunately, there is one problem with using wipers, and that’s the snow sticking on them.

If the wipers are frozen, the motor won’t work properly. Or the rubber will tear apart if they start wiping the glass.

The best way to remove the thick snow is using a plastic ice scraper. Also, it’s compact, so you can toss it inside the vehicle storage and carry it wherever you go.

There’s no special technique required in using a scraper. Either use it vertically or horizontally and remove the snow gently so that the blade doesn’t scratch the windshield.

Once you are done removing the snow, clean the windscreen with the wipers, and follow the next instructions.

Use a De-icing Spray for Better Results

The problem with snow is that it falls again, and your car’s windshield gets frosty over and over. But there’s a solution that keeps the windshield clean for longer.

You can use a de-icing spray to clean the stubborn fog quickly. Furthermore, the DIY spray is cheap, and you can make it with ingredients available around the house.

How to Prepare a De-icing Spray at Home

I’ve used two home-prepared windshield de-icer sprays, and both have worked fine by preventing the snow from forming a layer of frost on the glass.

Salt and Water Solution

You probably had used salt on your patio to prevent ice formation. Well, the salt melts the ice quickly, and the solution doesn’t require using hot water. All you need to do is mix some salt with water and pour it over the windscreen.

However, use the salt in the right quantity, as heavy salt can damage the glass.

  • Take two cups of water in a bowl and add one tablespoon of salt.
  • Stir well, and pour the solution in a spray bottle.
  • Remove the snow build-up using an ice scraper, and spray the solution over the windshield.
  • Let it sit for some minutes, and you will see ice melting.
  • Use the wipers to clean the residual ice.

If you are not sure about using salt on the glass. Consider the next de-icing solution, which is way more effective and is safe for the windshield, and window glass.

Rubbing Alcohol and Water

DIY De-icing Spray Solutions

Rubbing alcohol can quickly dissolve the ice, and if you are in a hurry, you should use this method. Moreover, it doesn’t involve using a scraper.

However, alcohol freezes if the temperature falls under 5°. If you live in an area with sub-zero temperatures, this method is for another day.

  • Take a spray bottle and fill it with two parts of rubbing alcohol and one part of water.
  • Remove the thick snow using your hand so that the solution can reach up to the glass.
  • Spray the windshield defroster solution on the entire windshield, and wait for some time.
  • You will see the ice melting within 2-3 minutes.
  • Use the windshield wipers to clean the sludgy snow.

Commercial De-icing Products Work Well for Removing Ice without Heat

Prestone Trigger Spray Windshield De-Icer

Commercial de-icing products are specifically designed to remove the snow build-up. Moreover, these products are convenient to use, and you can easily get rid of the snow without even using a scraper.

There are several benefits of using these products, including:

Quick and Lasting Solution

A commercial de-icer doesn’t just melt the ice, but it prevents the ice from forming again. Even if the snow falls on the glass, you can clean it with wipers.

Accurate and Even Application

There’s no need to worry about the de-icer damaging the modern car’s paintwork. These solutions are available in spray cans, and you can apply them evenly on the entire windshield.

Easier to Handle

I love how easy it is to handle a de-icer. No-fuss of preparing the solution, just take it out from your car, spray on the glass, and wait for the results.

Is De-icing Solution Bad for the Environment?

Well, the answer is yes! Using a de-icing solution is bad for the environment as it contains several chemicals. You should only use such solutions when in a rush or left with no other option.

Here are some eco-friendly ways to keep the windshield protected from snow, and thus the frost.

Cover the Windshield

OxGord Windshield Snow Cover

It would be great if you cover the windshield overnight. There are several good-quality windscreen covers available that you can use with your car. If there is less or no ice build-up, you don’t have to spend a lot of time defrosting the screen.

Park the Vehicle in a Garage

Parking your car under shade safeguards it from the elements of nature. Also, there are no hassles of removing the ice, as your car remains clean all the time.

Get the Windscreen Coated

There are several types of windscreen coatings available that protect the windshield from snow. These coatings don’t let the snow stick to the glass, and a few blows with the scraper will help you remove the ice.

Also Read: 15 Best Cars For Snow Driving

How to Defrost a Windshield in Rain?

How to Defrost Windshield in Rain

On rainy days, the fog builds up on the inside of the windscreen and not the outside. So, using the wipers will only clear the rainwater and not the frost.

In fact, the frost formed on rainy days can be extremely difficult to clean due to the higher moisture content in the air.

Turn the AC On

When it rains, the outside temperature falls down below the temperature of your car’s cabin. So turn the AC on with the lowest temperature setting, and see how it quickly clears the fog.

Use the defrost button to keep the flow of air towards the front and rear windshield. Once these screens get clear, turn the vents towards the window glass.

It would be great to keep the fan setting at 2-3 for quicker results. Furthermore, clean the fog using a soft and lint-free cloth if you are in a hurry.

Use a Window Cleaner Solution

How to Defrost a Windshield in Rain

The frost starts building up when the cold rainwater hits the windshield, and the inner temperature is hot. So, how to defog car windows in the rain without AC?

You can use a window cleaner solution like Rain-X 5071268 Glass Cleaner + Rain Repellent.

It doesn’t let the water stand on the glass, and there will be no frost at all. Spray this windshield defroster solution on all windows, and apply it properly following the instructions.

The thin barrier formed on the windshield rolls down the water quickly, and there will be less fog than before.

Get the Weatherstripping Replaced

Universal Self Adhesive Auto Rubber Weather Draft Seal Strip

I’ve seen numerous folks struggling with clearing the frost on a rainy day, even after using several coatings on the windshield.

Well, the deteriorated weatherstripping is another cause of frost build-up. Get in touch with your local car mechanic and get the weatherstripping checked.

These thin rubber strips attached to the doors keep the moisture out of the car and help in maintaining the temperature. Less moisture results in less fog, so get the stripping replaced if required.

What If the Fog Won’t Disappear?

If the windshield is still frosted, it may be due to some oil present on the glass. Sometimes people wax the windscreens to make them look shiny and scratch-free.

However, the oil present in such products holds the moisture and results in frost. Get some soda or rubbing alcohol solution on a soft cloth and clean the entire glass screen, then follow the above-mentioned defrosting tips and drive safely.

Also Read: Basic Car Tune Ups That Should Be Done Once In a Year

How to Defrost a Windshield in Summer?

Use these tips to beat the frost if it’s hot outside. These tips will help you maintain an optimum temperature inside the car that’s perfect for driving without getting sweaty.

Let Windshield Wipers Help Clear It

How to Defrost a Windshield in Summer

If the frost is on the outer glass, use the wipers to clean it! Don’t spray water on the windscreen. Instead, use the dry wiper technique to clear it in a single swoop.

Before you wipe the windshield, ensure the screen is clean from dust and dirt. If you see these elements, consider cleaning them with a soft cloth, and then use the wipers.

So the stubborn fog is still there? Use the second and most helpful tip.

Drive with the Windows Rolled Down

How to Defrost a Windshield in Summer

If you don’t have enough time to wait for the wipers to clear the fog, roll down the window glass. When the outer air hits the windshield, you’ll see fog clearing up quickly.

It’s a sure-shot way to defrost a windshield during summers.

Turn the AC Down

How to Defrost Windshield in Summer

If your car has cooled off, turn the AC off for some time. Or you can turn down the fan speed to avoid the screen getting foggy again.

Focus the AC vents on your face and legs instead of the car’s windshield and window glass. Up the AC’s temperature while driving to avoid frost from building up.

Use the Defrost Feature

Every modern car has a defrost feature. If you can withstand the blast of heat for some time, use this function to clear the windshield and the rear glass.

Turn the temperature knob to the red side to activate the heater. Once the glass gets clear, turn the defrost off, and you can use the regular AC on low fan speed.

Usually, the fog is on the outside of the glass during summers. Some use the wiper hack in the first place. If it doesn’t help, then you can use other methods to get better visibility.

Things To Do to Prevent Windshield from Fogging Up

Defrosting a windshield can be pretty tricky sometimes, and the best deal is to prevent it from fogging up. Here are the easiest hacks to ensure there’s no frost on the windscreen in any weather.

Apply Shaving Foam on the Inner Side

Gillette Foamy Regular Shaving Foam

Well, that shaving foam can do a lot more things than just making you look better. Take some foam and apply it to the inside of the windshield.

Use a sponge or a soft towel to spread it evenly all over and create a thin layer that’s not visible at all. Let the foam dry, and you can start driving.

A Pro Tip: Always use shaving foam and not shaving cream. Furthermore, use a sponge instead of a cloth, a sponge doesn’t scratch the glass and applies the foam properly.

Keep the Car Windows Open

Driving alone? Keeping the windows slightly cranked down will be really helpful in preventing the frost build-up. I usually keep the rear windows half open during the winters to avoid fog build-up.

Use the Fresh Air Mode

Always drive with your car on the Fresh Air Mode and not on the recirculation mode. The outer air helps in balancing the temperature inside the vehicle cabin, and it prevents the windshield from fogging up.

Apply an Ammonia-based Solution

Windex Glass and Window Cleaner Spray

The ammonia solution has similar properties as that of shaving foam, but it is more effective. The most popular solution is Windex, as it contains a good amount of ammonia.

Spray it on the inner windshield and rub it with a soft towel. It could be a little messy, so place some dry towels on the dashboard to keep your lovely car squeaky clean.

Apply the solution in horizontal and vertical strokes, and reapply it on the areas if required.

Use the Remote Starter Function

If your car comes with a remote starter function, start it 5-10 minutes before you want to head out. Keep the defroster on so that it clears the fog quickly. Also, it helps your car maintain a good temperature, so you can ride without shivering.

Use a Moisture Absorber

Snow Joe Blended Ice Melter

Moisture absorbers like rock salt work well when it comes to preventing your car’s windshield from fogging up. Take some salt in a sock, and place it on the dashboard near the windscreen. It will act as a filter for the incoming air and reduce the frost build-up as well.

Also Read: Basic Automotive Knowledge : Things To Know About Cars

Dos and Don’ts When Defrosting a Windshield

Defrosting a windshield can have some severe effects on your car. So here are some dos and don’ts you need to keep in mind in order to keep the vehicle in good condition.

When Using a Scraper

SubZero 60

When using a scraper to remove the ice, make sure it has a soft blade that doesn’t scratch the window glass. I have seen people removing snow using credit cards, keys, and even metal spatulas. You have to avoid these things at all costs.

When Using a De-icing Solution

The best deicing solutions are made at home, and I’ve covered some of the best DIY solutions in this article to get you rid of the ice. When using a de-icer, don’t use hot water, as it can damage the windshield.

Instead, use room temperature water as that works more effectively.

When Pressing the Gas Pedal

It is essential to warm up the car before using the heater. And in order to heat the engine, drivers press the gas pedal aggressively.

Let the car’s engine warm-up itself before you use the heater or AC for defogging. Being too aggressive on the car can hinder the engine’s lifespan, and it affects the vehicle’s drivability as well.

When Using the Defroster

If you don’t see the fog getting clear, it may be a sign of a faulty defroster. Always get the defroster inspected after some time. Usually, drivers don’t pay attention to the HVAC system, and it results in windshield fogging.

Frequently Asked Questions

Q1: How do you Defrost a Windshield without Cracking it?

A: There are a plethora of ways to defrost a windshield without cracking it. Start with using the AC in winters and heater in summers or rainy days. You can even use the wipers to clean the outer fog when it’s hot outside.

Never pour hot water on the windshield, as it results in sudden glass expansion and contraction, which leads to cracks and damages.

Q2: Does the Shaving Foam damage the Windscreen?

A: Not at all! Using shaving foam has no side effects on the windshield glass. However, you have to be extra careful when using such things. Rub little amounts of foam, and make sure you cover the entire window.

Q3: How many minutes does it usually take to Defrost the Windows of your Car?

A: Well, it depends on several factors, such as the stubbornness of the frost, the power of your vehicle’s HVAC system, and the method you are using.

Typically, it can take around 1-2 minutes to defrost the windscreen. However, it may take around 5 minutes in areas with sub-zero temperatures.

Q4: Is putting your Windshield Wipers up in Winter weather a Bad Practice?

A: It’s a good practice, especially for areas with extreme temperatures. Putting the wipers up protects them from the snow, and you can quickly de-ice the windshield.

Furthermore, you don’t have to warm up the car for longer if the wipers are up.

Q5: How to Defrost a Windshield with Homemade Heat Packs?

A: If the heater isn’t working and you have no other way left to clean the fog. Using homemade heat packs is a great idea, as you can defrost the glass on the go.

Here’s how to use it:

  • Take two old mittens or socks, fill them with uncooked rice, and place them inside the microwave for 30-40 seconds.
  • Grab these socks in each hand, and glide them gently over the inner glass. Make sure to move the sock continuously, and don’t stop it in one place.
  • The heat will get transferred to the ice, and it will help melt the snow without any risks of glass cracking.
  • Clean the snow slush using wipers, and use a soft cloth to clean the inner windscreen.

Q6: What causes a Windshield to suddenly develop a Crack when a Car Defrost is turned on, and it is warming up?

A: The reason is sudden expansion and contraction caused due to heat. When you turn on the heater without scraping off the excess snow, it results in cracking.

Use a scraper or de-icing solution before turning the heater on, and enhance the windshield’s lifespan.

Also Read: 25 Car Cleaning Hacks To Keep Your Car Spotless

Final Thoughts

Defrosting a windshield is no more a pain as these are the easiest way to do the job quickly and effectively. All the hacks that I’ve covered here are cheap and work well in all seasons.

Just be sure about your car’s HVAC system as it is the biggest weapon in your arsenal, as defrosting is the best solution to get rid of fog quickly.

Last update on 2021-09-21 at 00:39 / Affiliate links / Images from Amazon Product Advertising API

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