Quick answer: when rock chip repair works
Rock chip repair is usually the right choice when the chip is smaller than about a quarter (around 1 inch across), any crack is shorter than about 6 inches, the damage is not in the driver's direct line of sight, and it is not near the edge of the glass. If the damage is larger, sits right in front of the driver or in front of a windshield camera, or starts at the edge, you will most likely need a new windshield.
These are common industry rules of thumb, not hard laws, and every chip is a little different. A trained technician should look at it before you decide.
Size rules of thumb for chips and cracks
Windshields are made of laminated glass: two layers of glass bonded to a clear plastic layer in the middle. Most rock chips only damage the outer layer, which is why many of them can be repaired.
- Chips: bullseye, star and combination chips up to about 1 inch across are usually good candidates for repair. A quick test is whether a quarter covers the damage.
- Cracks: a single crack up to about 6 inches long, roughly the length of a dollar bill, can often be repaired. Some shops use a shorter limit, and anything longer usually means replacement.
- Number of chips: one to three small chips can typically be repaired. A windshield with many chips or pitting is often better replaced, because multiple repairs can affect clarity.
- Depth: if the damage goes through to the inside layer of glass, repair is no longer an option.
Location matters as much as size
The driver's line of sight
Even a well-done repair can leave a faint mark. If the chip is directly in front of the driver, in the area the driver looks through to see the road, many shops will recommend replacement so your view stays clear. California law also prohibits driving with a windshield in a condition that impairs the driver's vision.
Edge cracks
Damage within a couple of inches of the edge tends to spread quickly, because the edge of the glass is under more stress. Cracks that start at or run to the edge usually call for windshield replacement.
In front of a camera or sensor
Many newer cars have an ADAS camera mounted behind the windshield near the rearview mirror. Damage in the camera's field of view can affect how lane-keeping or emergency braking systems see the road, so replacement followed by ADAS calibration is usually the safer path.
Why chips spread in Inland Empire heat
If you drive in Colton, Riverside, Fontana or San Bernardino, you know summer afternoons regularly climb past 100 degrees. Heat is hard on damaged glass. A small chip turns into a cracked windshield for a few common reasons:
- Fast temperature changes: blasting cold A/C on a sun-baked windshield, or washing a hot car with cold water, puts sudden stress on the glass.
- Daily heating and cooling: glass expands and contracts with temperature, which works on the weak spot day after day.
- Road vibration: potholes, speed bumps and freeway expansion joints can push a chip into a crack in seconds.
Until the chip is fixed, park in the shade when you can, avoid aiming the defroster or A/C straight at the glass at full blast, and cover the chip with a piece of clear tape to keep dirt and moisture out. Then get it repaired as soon as possible. We serve drivers across the area, including Riverside and Fontana.
What rock chip repair does and doesn't do
During a repair, the technician cleans out the chip, uses an injector tool to fill it with a clear resin under pressure, and then cures the resin with UV light. The whole process usually takes well under an hour.
What repair does:
- Helps stop the chip from spreading into a crack
- Restores much of the strength at the damaged spot
- Makes the chip much less noticeable
- Keeps your original windshield and factory seal, and usually avoids the need for ADAS calibration
What repair doesn't do:
- It won't make the damage completely invisible; a small blemish may remain
- It can't fix long cracks, edge cracks or damage to the inner layer
- It won't reverse a crack that has already spread
Repair is also kind to your wallet. It typically costs much less than a new windshield, and many insurers cover chip repair with little or no deductible. See our guide on windshield replacement cost in California for typical ranges.
Repair or replace: a quick checklist
Run through these questions while you look at the damage. The more "yes" answers you have, the more likely rock chip repair will work.
- Is the chip smaller than a quarter?
- If there is a crack, is it shorter than a dollar bill?
- Is the damage outside the area right in front of the driver?
- Is it at least a few inches away from the edge of the glass?
- Is it outside the area in front of the camera near the rearview mirror?
- Are there only one to three chips on the windshield?
- Is the inside surface of the glass smooth, with no damage you can feel?
If you answered "no" to any of these, replacement may be the safer choice. That does not always mean a long wait: same-day windshield replacement is often available when your glass is in stock.
One more tip: do not wait for a chip to "see what happens." Dirt and moisture work their way into an open chip over time, and that can make the repair less clear. A fresh chip that is repaired within days usually turns out better than one that has been collecting grime for months. And if a crack has already started spreading from the chip, measure it before you call so the technician has a better idea of what to expect.
Not sure? Send us a photo
The easiest way to decide is to let a trained technician look at the damage. Text a clear photo of the chip or crack, with a coin next to it for scale, and we will tell you whether rock chip repair will work or whether replacement is the better call.
Cano's Auto Glass is 100% mobile with free mobile service, so we come to your home or work. Call or text (714) 718-4692 Monday to Saturday, 7am to 6pm, or request a quote online. Hablamos español.
