Windshield Haze: A Guide

Does it seem impossible to fully clean your front windshield? If the glass seems permanently dirty or if extensive glares are a problem even after washing, your windshield may have developed permanent hazing. Unlike haze from dirt or condensation, permanent hazing is from damage to the glass.

What Is Hazing?

Permanent hazing is from a combination of scratches, pits, and etching on the surface of the glass. It primarily affects exterior surfaces, but interior surfaces are not immune. Dirt can easily become trapped in the scratches and pits, making the problem of hazing worse.

It typically first appears as minor scratches or shallow pits. You may only notice it when the sun or a headlights hit the glass, since bad glares are a side effect of even minor hazing. Over time, the hazing can worsen to the point that window loses all clarity, which results in a dull glass surface that is no longer easy to see through.

How Does It Happen?

There is no single cause of hazing. Most hazed windows become that way from a combination of factors. These factors often fall into three main categories.

1. Sand

If you live in a sandy region or near a dirt road, wind can lift up sand particles and literally sandblast the windshield. The result is minute scratches and small pits all over the glass. Sandblasting damage tends to start out as minor damage, but repeated exposure can lead to major glass damage.

2. Wiper Damages

Windshield wipers can contribute to hazing due to scratches that may be left behind. Damaged wiper blades can trap hard dirt particles against the glass, which are then scraped back and forth each time you use the wipers. Wiper scratches can become deep very quickly due to the repetitive nature of the damage.

3. Acid Etching

Acid etching is from weak acids eating through the top layer of glass to create an etched haze. Much like sand damage, acid damage tends to build up over time, so it is repairable if you catch it early enough. Acidic bird droppings or exposure to acids in pollution and acid rain are the primary culprits.

Is Hazing Preventable?

Some types of hazing are preventable, while others are more difficult to avoid because the causes are environmental. For example, sand damage may be preventable if you are able to park your car in a garage and avoid driving on windy days, but you will not be able to avoid it completely if you drive in a susceptible area.

Wiper damage is always avoidable. By simply replacing your wipers before they become damaged, you can prevent a lot of damage. Further, avoid using wipers on dry glass, since scratches are more likely to occur if no moisture provides lubrication for wiper blade movement.

As for acid etching, the environmental acids that a windshield is likely to have exposure to act slowly. This means you can avoid acid damage by washing your car frequently and by parking under a cover when possible. Never allow bird droppings to sit on the glass for long periods of time without washing your windshield.

Do You Have Repair Options?

Two main repair options are usually the best, which you may use alone or in combination. Your windshield glass service can advise on which methods are most likely to refurbish your hazed glass.

1. Polishing

Minor hazing can be buffed out of the glass. Windshield glass has several layers, and minor hazing only affects the outermost layer of the glass. A special abrasive pad buffs off the damaged layer of glass. A polishing pad is then used with a polishing compound to smooth the glass so that it regains the clarity necessary.

2. Acrylic Coatings

Acrylic resin scratch fillers are another option. These fillers are necessary for use over a badly hazed window, but they can fill deeper scratches that are not in the driver’s critical vision field. Coatings are a good option if you have a few deeper scratches on the passenger side from a windshield wiper.

When Is Replacement Better?

Keep in mind that repair is only possible if the hazing is relatively minor. Any deep scratches or pits in the critical vision area of the driver aren’t usually repairable, as glares and a loss of clarity can still impact the driver's view through the windshield.

Extensive hazing with many etches or pits may also be best repaired by replacing the windshield. You lose some clarity with any repair, which is not an issue with minor damage but can be very detrimental with more severe damages.

Contact MS Glass Outlet if you need help for your hazy windshield. We look forward to helping you have the best windshield possible for your car. Let us know what questions or concerns you may have about this or any other windshield issue.