How to Stop a Windshield Crack from Spreading

Co-authored by Ed Beery and Luke Smith, MFA

Last Updated: November 2, 2022 References

Windshield cracks happen all the time⁠—all it takes is a stray pebble to cause some major problems. And they’re not just annoying, they can be a serious safety concern, too, distracting your eyes from the road and weakening your windshield. We’ve got the best quick fixes to stop those little nicks from spreading, at least until you can get your windshield serviced by an auto glass professional.

Things You Should Know

A windshield repair kit is the best way to fix small nicks and cracks.
Filling a crack with super glue or nail polish is a common method of stopping a crack from spreading.
Applying clear tape over a crack will prevent more debris from entering the crack and making the problem worse.

Method 1

Method 1 of 4:

Using Super Glue or Nail Polish

1
Clean the windshield with glass cleaner. Apply window cleaner to a rag or microfiber cloth. Rub the rag or towel over the cracked area to remove any dirt or debris.^{[1]
X
Research source} Allow the windshield to dry completely before you move on to the next step.
- Be sure not to spray any cleaner directly on the area, as this can get inside the crack and interfere with the repair process.
2
Use a small, sharp object to clear any debris from the crack. Once the crack is wiped clean, find a push-pin, sewing needle, or another thin and sharp object to insert into the crack and carefully nudge any debris like glass or dirt out from the crack.^{[2]
X
Research source}

Advertisement
3
Apply super glue or clear nail polish to the crack. Carefully squeeze a small amount of super glue into the crack—just enough to fill the crack without causing a mess. Then, carefully wipe away the excess liquid with your cleaning rag. Let the glue dry for at least two hours before getting back on the road. ^{[3]
X
Research source}
- If you’re using nail polish, be sure to use clear nail polish so that the fix is transparent and not too distracting.
- Super glue and nail polish fill the crack and help prevent further damage, but they're not permanent solutions. You'll need a repair or even full replacement in order to completely fix any chips or cracks.

Method 2

Method 2 of 4:

Applying Tape to a Crack

1
Use glass cleaner to clean the windshield. Spray a microfiber towel or clean rag with window cleaner. Gently rub the rag or towel over the cracked area so the space around the crack is free of debris. ^{[4]
X
Research source} Allow the windshield to dry completely.
- Don’t spray the glass cleaner directly onto the damaged area, as this can interfere with the repair process.
2
Remove small debris from the crack with a push pin or other sharp object. After you clean the windshield crack, find a push-pin, sewing needle, or another thin and sharp object. With the sharp end of the pin, scrape out any debris that might have found its way into the crack, including glass or dirt.^{[5]
X
Research source}
3
Cover the crack with tape. Use strong, clear tape, like packing tape, to seal the crack. Make sure the crack is completely covered to prevent any further dirt or debris from finding its way inside. Use transparent tape that will allow you to drive and see through your windshield without too much distraction.
- Tape will only cover the crack and can help prevent further damage, but don’t stop there. Use a windshield repair kit or visit an auto body shop to fully repair or replace the windshield.

Method 3

Method 3 of 4:

Using a Windshield Repair Kit

1
Purchase a windshield repair kit. The best way to stop a crack is to fix it! Windshield repair kits are available at most auto shops and hardware stores and are a cost-effective way of removing any chips or small cracks.^{[6]
X
Research source}
- Syringe adhesive kits usually include adhesive liquid and a syringe, and involve injecting the adhesive into the crack with a syringe.^{[7]
  X
  Research source}
- Suction adhesive kits typically include a resin formula to inject into the crack, as well as an applicator that suctions to your windshield.^{[8]
  X
  Research source}
2
Clean the windshield and remove debris from the crack. Spritz a rag or microfiber towel with window cleaner. Gently rub the rag or towel over the cracked area to remove any dirt or debris. Then, use a push-pin, sewing needle, or another thin and sharp object to gently remove any debris.^{[9]
X
Research source} Allow the windshield to dry completely.
- Careful not to get any window cleaner inside the crack itself. This can interfere with your repair!
3
Apply the resin or adhesive with the included applicator and let the area dry. Once the damaged area is clean and free of debris, insert the adhesive into the kit’s applicator. Then, position the applicator directly above the crack and carefully inject the adhesive into the area and let it dry. ^{[10]
X
Research source}
- Each kit comes with its own particular instructions and methods, so be sure to follow the instructions included in your particular kit!

Method 4

Method 4 of 4:

Protecting Your Windshield From Further Damage

1
Avoid rough or bumpy roads. Too much jerky motion can disturb the crack and cause it to spread. Use a GPS to alter your route to avoid bumpy roads that may cause the crack or chip to become worse.^{[11]
X
Research source}
2
Avoid driving in the rain. Rain can carry small debris that might find its way into the crack and cause more problems. Try to drive only on clear, dry days in order to prevent further damage to your windshield.^{[12]
X
Research source}
3
Park under a shelter to avoid severe temperature changes. Severe temperature changes can also affect existing windshield cracks. Keep your car indoors if possible in order to keep it at an even temperature. If you can’t park inside, try parking in the shade, or in the same location from day to day.^{[13]
X
Research source}

*A chipped or cracked windshield left in the elements on a day with large temperature changes may lead to significant additional cracking.

Expert Q&A

Question

Does heat or cold make windshield cracks spread?

Ed Beery
Automotive Specialist
Ed Beery is an Automotive Specialist and the Owner of InTechgrity Automotive Excellence based in Denver, Colorado. With more than eight years of experience, he specializes in providing maintenance and repair services for both individuals and companies. Ed and the InTechgrity Automotive Excellence Team are approved by the American Automobile Association (AAA) for repairs and are Automotive Service Excellence (ASE) certified.

Ed Beery

Automotive Specialist

Expert Answer

Definitely—windshield crack spreading is often caused by temperature changes, along with vibrations and pressure on the windshield. If possible, keep the vehicle inside and in a more consistent temperature environment. This will also reduce the risk from temperature changes from your defroster/heater blowing on a cold windshield or cold AC air hitting a hot windshield.
Question

What can you do to a windshield to stop a crack?

Ed Beery
Automotive Specialist
Ed Beery is an Automotive Specialist and the Owner of InTechgrity Automotive Excellence based in Denver, Colorado. With more than eight years of experience, he specializes in providing maintenance and repair services for both individuals and companies. Ed and the InTechgrity Automotive Excellence Team are approved by the American Automobile Association (AAA) for repairs and are Automotive Service Excellence (ASE) certified.

Ed Beery

Automotive Specialist

Expert Answer

When the car is in a place to do so, drill a shallow dimple (with the smallest diameter hole possible) into the windshield at the end of a crack line to create an endpoint for the crack and to control spreading. Glass drill bits are widely available at hardware, tool, auto repair, and online stores.
Question

Why does my windshield crack keep spreading?

Ed Beery
Automotive Specialist
Ed Beery is an Automotive Specialist and the Owner of InTechgrity Automotive Excellence based in Denver, Colorado. With more than eight years of experience, he specializes in providing maintenance and repair services for both individuals and companies. Ed and the InTechgrity Automotive Excellence Team are approved by the American Automobile Association (AAA) for repairs and are Automotive Service Excellence (ASE) certified.

Ed Beery

Automotive Specialist

Expert Answer

You might be driving it in poor or improper conditions. Always avoid heavy snow and high speed driving, and be mindful of wind speed and direction. When driving into the wind, your speed plus the wind speed can mean pressure equal to 100 mph plus winds, which is a lot of pressure on a windshield.

Things You’ll Need

Windshield repair kit (optional)
Super glue (optional)
Clear nail polish (optional)
Clear tape (optional)

Warnings

The best way to stop a crack from getting bigger is to get it fixed. Visit an auto glass shop to have the crack professionally sealed or the windshield replaced, if necessary.

⧼thumbs_response⧽
Helpful 0 Not Helpful 0
DIY methods can yield poor results and have a good chance of rendering a professional, quality repair impossible.

⧼thumbs_response⧽
Helpful 0 Not Helpful 0
If the situation is so bad that there is concern that the windshield may break apart, do not drive the vehicle if possible and have the windshield repaired or replaced.

⧼thumbs_response⧽
Helpful 0 Not Helpful 0