It is unsafe to drive with a hole in the car's windshield that is bigger than a couple of inches in size. If there is a hole in the car's windshield then the windshield, as a unit must be replaced. A cavity in any of the car's windows creates vulnerability for the driver and the passengers. This means that the occupants of a car with damaged windows are within range of any projectiles such as rocks or road debris that may fly through the cavity or further damage it. Snow rain and hail may damage the car’s interior or cause injury to the car's occupants.
The front and rear windshields are the largest areas of glass on the body of a vehicle and these must be in good condition for the driver to be in compliance with road safety laws. A vehicle's front windshield is rigid and strong enough to contribute to the overall strength of a car’s frame; it also helps with the deployment of airbags.
A windshield must be replaced with auto glass, which these days must be laminated glass. To manufacture a windshield two sheets of glass are bonded together with a layer of polyvinyl butryal [PVB] between them. The sheets of auto glass are then shaped and cut to fit the front window pane of the car and through the use of a molecular bonding process which fixes the windshield in place, the vehicle becomes airtight and waterproof.
Windshields are replaced by technicians who are trained to do the job, either in a garage or by the road. Before the windshield is replaced, a windshield technician will carefully assess the damage that has been done to the vehicle, both inside and outside. The shards of glass that remain in the window frame, attached by the weather stripping, will need to be removed. Once this has been done, a new windshield can be installed.
A new windshield must be carefully bonded and sealed into the window frame of the vehicle, to recreate full weatherproofing. To make the process more convenient, some companies use special quick-setting sealants so that the vehicle can be driven away in a short period of time.
If you decide to remove an old or damaged windshield yourself, for instance because this job is not covered by an insurance policy, there are several other tasks that will need to be performed. A home handy man who takes on this task will need to have the right tools for the job.
The old weather stripping must be removed, using a Stanley knife. New windshield clips must be gently hammered into the top of the windshield’s frame. A urethane sealant which has been applied to the windshield socket or frame will hold the new windscreen in place. This is the point at which new windscreen wipers and new weather stripping should be re-affixed to the windshield. Debris such as broken glass, or scraps from the windshield’s reinstallation may remain on the floor inside the car; so carefully sweep or vacuum them up.
It is best to wait a while before driving the vehicle, to let the urethane sealant settle and dry completely. A good day’s work has now been done, and the new windshield should protect the car’s occupants just as well as the old one has done.
Other things to remember are the vehicle's brand and model number, because each windshield socket is a different size and shape. The vehicle's brand name and model also influences the style of the features that may be built into the windshield itself. The may be a shade band of tinted glass at the top of the windshield on the driver's side, or the windshield may be wired for heating with fine tungsten wires embedded in the glass.
Some windshields are tinted to provide protection from infrared rays – this is a way of keeping the vehicle cooler. The rubber molding or weather stripping will also need to be fitted carefully to each different type of vehicle.
To keep your family and passengers safe, always replace a windshield the minute it shows signs of permanent damage.