Each time you go for a car windshield replacement, you may wonder if you can drive right after the windshield is replaced. The answer is NO. You should wait for at least an hour before you should drive. But there are many factors on which this time depends and ideally, your service provider should inform you about it.
The main reason why you should sit is the adhesive used in windshield replacement. Adhesives have different curing time. Though most industry-approved adhesives tend to cure with-in an hour after applying to the car body. It basically depends on environmental factors like temperature and humidity.
If you drive immediately after the new windshield is replaced, it can disorient the windshield from its position or may cause some gaps between the windscreen and car body. In case of any mishap/accident, this can be fatal. The windshield is not only to look through or just to keep air and dust away from you. It’s an integral part of the car’s structural strength. Windshield holds the car roof and hence in case of an accident your car roof doesn’t collapse immediately. If your windshield orientation is not correct just because you have driven your car immediately after windshield replacement, it’s structural strength is compromised. Now your car’s roof is prone to collapse in case of a serious accident. Even if something fell off on the roof it will collapse as this support base is compromised.
Also, windshield gives support to the airbag deployment during an accident. If your car windshield is not at the correct position or loose due to ineffective PU sealant curing it can affect the airbags functioning.
Minimum time to drive after a windshield replacement is 1 hour. In some cases, it can be more than an hour. It’s basically the time that is required by polyurethane/PU sealant to cure. Though to cure completely, it may take 2-3 days, but once its outer layers get cured, you can drive your vehicle.
Hence, it is important that your workshop inform you of the minimum time you should wait before driving whenever you get a new car windshield. Also, you should also ask if they fail to do so. After all, your safety is your responsibility.
The answer is YES, you should. The tapes at the top or on the side of the windshield are to keep the windshield in position after the primary layer of polyurethane is cured and these are just precautionary. So, these tapes support the adhesive to keep the windshield at the correct position for about 24-48 hours after new windshield replacement so that inner layers of PU sealant also get cured properly.
A few years ago, the automotive industry used the term Safe Drive Away Time (SDAT) but discouraged its use in favor of Minimum Drive Away Time. As the term, Safe can be legally incorrect and can be a liability for the service provider. Technically SDAT and MDAT are two different terms and SDAT was used wrongly instead of MDAT.
SDAT is the safe time in which PU Sealant cures to the level that you can drive your car safely without worrying about the windshield disorientation due to jerk. While MDAT is the minimum time after which you can drive your car normally, but you need to take care of the speed to avoid any kind of a serious jerk to the windscreen.
Now that you know that to maintain safety you should at least keep the car ideal for at least an hour after new windshield replacement. Let’s examine what can affect the Minimum Drive Away Time (MDAT):
Curing depth in mm in first 24 hours for Sikaflex
Generally, in summers at high temperature and high humidity, the curing rate is higher than in winters. In some countries under sub-zero temperatures, special PU sealants need to be used.
