What Causes Windshield Haze and How to Remove It!

Have a thin coat of haze or film on your windshield? This can be dangerous, especially at night and or when it is raining. In this blog, I’ll share a few common reasons for why this happens, and how to remove it using a few products you may already have at home.

Once you have your windshield crystal clear, I’ll share a few tips I have found to be helpful for me in keeping your windshield crystal clear.

So what causes windshield haze?

Believe it or not, that film on your windshield may not be what you think. While there are several common causes to haze forming on your windshield, both on the inside or outside of the windshield surface, some actually surprised me.  Here are a few common reasons:

Offgas from vinyl or plastic

offgas haze on windshield

Vinyl and other plastics, when heated can vaporize and eventually settle on the surface of your windshield, causing a smoky film from the inside. I’ve experienced this in my truck, and is a phenomenon I was honestly not aware of until recently.

This is usually more of a problem for new cars, but some say it may be a problem for up to 150k miles.

I began to notice after cleaning the outside of the windshield, there still appeared to be a haze on the inside. This seemed odd to me since I keep the inside pretty clean, and assumed it was overspray from using vinyl cleaners on the dash. When the haze continued to form, I later realized that offgas was the root of the problem.

Other possible causes in addition to a vinyl dash are vinyl seats or seat covers. You’re more likely to start noticing offgas haze during the summer, especially if you park outside in the sun.

Smoking

Smoking may also be the culprit, and can actually be quite difficult to get off. It’s especially important to remove carcinogens, as they can be more difficult to remove over time.

Engine or heater coolant

It’s not unheard of for a leak in your engine or heater coolant to produce a green or colored haze on your windshield that enters you vehicle usually through the front vents. This is usually characterized by a strong smell and can leave a greenish or colored tint to the inside of your windshield.

You always want to address any leaks as soon as possible to avoid breathing in any dangerous chemicals.

Hard water, acid rain, dirt, or other substances on the outside

If your hazing is not caused by any offgas, but seems to only be a problem on the outside of your car’s vehicle, this can be  caused by a variety of substances like:

  • Acid rain
  • Tree sap or pollen
  • Hard water

This is probably the most common exterior haze that forms, and should be easiest to remove.

If you regularly deal with hard water spots, I outline s few options for removing and preventing them in this blog post.

5 Products to Remove Haze from your Windshield

Products to Remove Windshield Haze

There are several products you can use to remove windshield haze, that you can either make yourself or buy in stores. Depending on what caused the hazing, you may need to apply a little more pressure than you normally would when cleaning the outside of the windshield.

1. White vinegar and water [General multipurpose]

This solution is one of the most effective home remedies I’ve heard works is white vinegar and water at a 10% vinegar to water ratio. You may want to up the percentage depending on how severe your hazing is. Works well with

2. Ammonia-free Glass Cleaner Spray [General Multipurpose]

Armour All makes a pretty good glass cleaner that you can use to treat your windshield that is ammonia-free that you can pick up on Amazon for about 7 bucks.

Keep in mind, this is different from Amour All protestant, which you should never apply to windshields (which can cause hazing).

3. Invisible Glass or another Glass Cleaner Aerosol Product  [For Maximum Clarity]

This is one of the best products for making your windshield as clear as possible once cleaning has occurred. Usually works best when the surface is completely clean.

4. Mr. Clean Magic Eraser [For Removing Stuck on Substances]

When dipped in water, a magic eraser can do a great job of removing stuck-on substances like smoke residue or offgas, and is great because while abrasive, you don’t have to worry about scratches.

5. Rubbing alcohol  [For Hard to Remove Substances]

For smoke residue and other stuck-on substances, rubbing alcohol is a great option to try when traditional glass cleaners don’t seem to be working.

I recently picked up a spray bottle for a couple of bucks for cleaning windows, and are really handy to have around.

Tips When Cleaning

  • Use microfiber towels if you have them in order to prevent streaking. Using towels will allow you to apply more pressure and won’t leave behind particles as paper towels can. Newspaper has also been known to be effective for cleaning windows
  • Avoid ammonia-based cleaners on tint. If you are cleaning windshields and windows, be sure to avoid ammonia-based cleaners (they can ruin tinting)

How to Prevent Windshield Haze

Exterior

  • One product that I like to use to prevent exterior windshield haze in Rain-X. It comes in a few different varieties, but I prefer the aerosol.  Not only does it help prevent water from drying and possibly forming a film, I’ve found it also does a pretty good job in making it difficult for other substances or particles (like pollen) from sticking.
  • A haze will form when applying Rain-X which is normal. Once dry, simply sprinkle with water to remove excess haze. Be sure to read the application instructions to best results and do not apply to the interior surface!

Interior

  • Especially if you park outside and deal with offgas, a good windshield sunshade is a great idea for keeping your car as cool as possible during the summer months. These come in a variety of types, and can even be personalized with your favorite team’s logo!
Free eBook: 25 Essential Detailing Products for Beginners

Conclusion

While haze may seem harmless, I’ve known it to obstruct driving for me (especially at night, especially in the fog and rain). The best thing to do is to keep your windshield clean, and avoid parking outside when you can.

Have any other ideas or suggestions that have worked for you? Let us know in the comments.

Leave a Comment