DIY Windshield Chip Repair vs Professional Windscreen Chip Repair: What’s the Difference?
- Paula McCoy
- Jun 19
- 6 min read
A windscreen chip repair might seem like a minor issue, but if left untreated it can quickly turn into a large crack requiring a full windscreen replacement. Many vehicle owners wonder whether they should attempt a DIY repair kit or take their vehicle to a professional auto glazier.
In this blog, we explain how professional windscreen chip repairs work, the difference between DIY and professional windscreen chip repairs, and why professional repairs are usually the safest and most reliable option.
What Is a Windscreen Chip Repair?
A windscreen chip is a small impact point or crack usually caused by stones or debris flicking up from the road and hitting the front windscreen. Windscreen Chips can also occur from falling objects, birds, or other unexpected impacts while driving or parked.
When the windscreen is struck, the impact creates micro-trauma within the laminated windscreen. This opens a small cavity in the glass which traps air, moisture, and dirt. The dark or black appearance you often see inside a windscreen chip is trapped air within the damaged area.
This trapped air is what causes the crack to continue spreading over time. The purpose of a stone chip repair is to remove the air and replace it with specialised resin to strengthen the glass and reduce the chance of further cracking.
A common misunderstanding is that windscreen chip repairs completely disappear after repair. This is not usually the case. Even after a professional windscreen chip repair, the damage may still remain slightly visible, but it should appear much clearer and structurally stronger if repaired correctly.
What Causes Windscreen Chips and Cracks?
Windscreen chips can happen at any time while driving or even while parked. Common causes include:
Loose stones from roads
Following trucks or construction vehicles
Gravel roads
Falling branches or debris from trees
Sudden temperature changes
Road vibrations
Vehicles parked under trees or frequently driven behind heavy vehicles are generally more at risk.
How a Professional Windscreen Chip Repair Works -
Professional windscreen chip repairs are carried out by trained automotive glass technician using specialised tools and high-quality chip repair resin.
At professional auto glass businesses, automotive glass technicians are commonly trained through the Building and Construction Industry Training Organisation (BCITO) Auto Glazing qualification. This training teaches automotive glass technicians how to safely repair windscreens and windscreen chip repairs while meeting New Zealand safety standards.
Step 1 – Cleaning and Preparing the Windscreen Chip Repair -
The automotive glass technician first cleans the damaged area and checks the severity of the windscreen chip. Any loose glass or contamination is removed.
Step 2 – Drilling the Impact Point
A professional chip repair kit may include a precision Dremel drill with specialised drill bits designed specifically for automotive glass repairs.
The automotive glass technician carefully drills into the impact point to create a controlled opening for the chip repair low viscosity. It is important not to drill too deep, as this can damage the laminated layer underneath the glass.
Step 3 – Injecting the Windscreen Chip Repair Resin
A bridge and injector system is then attached over the windscreen chip. This device creates pressure and vacuum cycles that force the chip repair resin deep into the crack and remove trapped air.
The windscreen chip repair low viscosity resin is left to settle for several minutes so it fully spreads through the damaged area.
Step 4 – Sealing and Curing
Once the stone chip repair crack is filled, a higher viscosity finishing chip repair resin is applied over the surface. A curing strip is placed over the car windscreen chip repair to create a smooth finish.
The windscreen chip repair is then cured using a specialised UV lamp or direct sunlight for several minutes until hardened.
Step 5 – Finishing the Windscreen Chip Repair
After curing, excess windscreen high viscosity pit fill resin is carefully scraped away using a flat blade. The area may then be polished to improve the final appearance and help reduce visibility of the vehicle windscreen chip repair.
Professional Windscreen Chip Repair Costs in New Zealand
Pricing can vary depending on the business and whether the repair is completed in a workshop or as a mobile windscreen chip repair service.
At Maverick Auto Glass:
Workshop windscreen chip repairs: approximately $80 including GST
Mobile windscreen chip repairs: approximately $100 including GST
Additional windscreen chips on the same windscreen: approximately $35 extra per chip
Larger franchise businesses may charge between $120–$140 including GST for a single chip repair and they don’t offer mobile windscreen chip repair service.
is chip repair covered by insurance?
Many insurance policies in New Zealand also cover windscreen chip repairs if glass cover is included in the policy.
DIY vs Professional Windscreen Chip Repairs
1. WOF and Legal Compliance
One of the biggest differences is compliance with New Zealand Land Transport standards.
Professional stone chip repairs completed by qualified automotive glazing technicians can meet WOF and COF requirements. Businesses may also provide repair declarations or certificates confirming the windscreen chip repair has been completed to industry standards.
DIY windscreen chip repairs generally do not provide certification and may still fail a WOF inspection if the vehicle stone chip repair is poor or remains unsafe.
2. Equipment Quality
DIY kits are made for general consumer use and usually contain basic tools and lower-grade resin.
Professional repair systems use:
High-quality repair resin
Precision injectors
Specialised drill bits
UV curing lamps
Professional bridge systems
Glass probes and finishing tools
These tools allow automotive glazing technicians to complete stronger and cleaner auto glass chip repairs.
3. Technician Experience
Professional automotive glazing technicians are trained to assess damage correctly and prevent further cracking during the windscreen repair process.
DIY car windscreen chip repairs rely entirely on the user’s skill and technique. Incorrect pressure, contamination, or poor curing can easily make the crack worse.
4. Durability
DIY repairs may temporarily keep dirt and moisture out, but they can fail over time due to:
Temperature changes
Road vibrations
Poor resin quality
Air bubbles trapped during repair
Professional windscreen repairs are designed to restore structural integrity as much as possible and often come with warranties.
DIY Kits vs Professional Stone Chip Repair Kits
DIY automotive glass repair kits are commonly sold at automotive stores such as Supercheap Auto or Repco and generally cost between $20–$50.
Professional automotive windscreen chip repair systems can cost over $2,000 and contain significantly more advanced equipment.
Key Differences Include:
Professional Drill Systems
Professional systems use specialised Dremel drill bits designed specifically for controlled glass drilling without creating additional cracks.
Advanced Injector Systems
Professional bridge and injector systems create proper seals against the windscreen to minimise trapped air during resin injection.
Multiple Resin Types
Professional windscreen repairs commonly use:
Thin penetrating resin for deep crack filling
Hard finishing resin for surface sealing
This creates a stronger and more durable repair.
UV Curing Equipment
Professional UV lamps provide controlled curing conditions, helping the resin harden correctly.
Direct sunlight can sometimes cure resin too early during DIY car windscreen chip repairs, especially when working outdoors.
Surface Finishing
Professional kits also include polishing compounds and finishing tools that help improve the cosmetic appearance of the windscreen repair.
Why Timing Matters During Windscreen Repairs
Correct curing time is extremely important during windscreen chip repairs.
If resin is not cured long enough, the stone chip repair may remain weak or fail later. If cured too early or too long, the resin may not bond properly and could trap air or contamination.
Professional automotive glazing technicians understand the correct curing times and environmental conditions needed for a successful car windscreen chip repairs.
Is Professional Windscreen Chip Repair Worth It?
In most cases, yes.
Prevent cracks from spreading
Restore structural strength
Improve WOF compliance
Reduce long-term repair costs
Provide warranty protection
Improve repair appearance
At Maverick Auto Glass, customers also receive repair documentation to help support WOF compliance. If a windscreen stone chip repair later fails and requires a replacement windscreen, the repair cost may also be deducted from the replacement price in some cases.
Final Thoughts
Although DIY car windscreen chip repair kits may seem cheaper upfront, professional windscreen chip repairs provide better structural integrity, improved appearance, safer results, and greater long-term reliability.
A professionally repaired windscreen chip repair can save you from needing a full windscreen replacement and help keep your vehicle safe on New Zealand roads.
If you notice a chip in your windscreen, it is always best to repair it as soon as possible before it spreads further.
Getting a professional to repair a windscreen chip is by far the safest option. Those DIY kits are just a plastic injector and some resin to try and force into a crack without drilling any hole for the resin to spread through the damage properly. Great information! Thanks Paula!