Charlotte Auto Glass from Impex’s David Cox Rd shop

The first question on any windshield is whether it can be saved. Three things decide it: the size of the damage, how deep it goes and where it sits on the glass. Impex’s own guide is that a repair may be possible when the damage is small, shallow and away from the edges. Damage that is large, deep or runs to the edge usually means a new windshield.

There is also a published standard. ROLAGS, the Repair of Laminated Automotive Glass Standard run by the National Windshield Repair Division, says that stone breaks up to two inches in diameter and single line cracks up to 14 inches are repairable. Those are outer limits, not a promise. Shops also use rules of thumb: Impex speaks of small chips as smaller than a quarter, and a common industry rule of thumb is damage smaller than a dollar bill. Neither is a law.

The technician makes the final call at the car. A chip right in front of the driver may be small enough to fill and still be better replaced, because a repair leaves a faint mark where the stone hit.

Many cars on Charlotte roads now have a forward camera mounted at the top of the windshield. It runs lane departure warning, collision braking and adaptive cruise control. I-CAR, the collision repair training body, lists removing the windshield as one of the events that may require the camera to be aimed again. When a new windshield goes in, the camera sees the road through new glass and may need to be reset to the car’s specifications.

The Insurance Institute for Highway Safety reports that forward collision warning with automatic braking cut rear-end crashes in half. That is the system a misaimed camera can confuse. Impex performs ADAS calibration on site immediately after a windshield replacement, static or dynamic as the car requires, and says calibration takes between 30 minutes and 2 hours. Static calibration uses targets set in front of the car; dynamic calibration means driving the car at a set speed for a set time or distance.

Radar is different. Forward radar sensors usually sit in or behind the front bumper or grille, not the windshield, so a windshield job does not normally call for radar calibration.

In North Carolina, glass damage normally falls under the comprehensive part of an auto policy. The NC Department of Insurance lists breakage of glass among comprehensive losses, and says the coverage pays the cost of repair less any deductible. North Carolina has no law that sets the glass deductible to zero, though some policies include full glass coverage. Check yours.

Two more rules matter. Under G.S. 58-3-180 the claimant chooses who repairs the vehicle, and the insurer pays the same amount whichever shop you pick. And because a rock chip is not an at-fault accident, a comprehensive glass claim does not add Safe Driver Incentive Plan points, though insurers may look at how often you claim. The glass insurance claims guide goes through it step by step.