This might sound obvious – even annoying when mentioned – but the major problem when getting your vehicle ready to drive in extreme weather conditions isn’t the danger of poor visibility or the risk of damage to the windows.
It is impatience.
Always make sure you allow extra time on your journey to cope with removing ice from the windows properly – not just the windscreen.
The primary reason why you need to do this is safety but it also is a legal requirement and could affect your insurance cover in the event of an accident. When using the road during icy or stormy conditions, there can be many obstacles along the route which require additional attention, aside from pedestrians, cyclists and other road users, drivers need to see clearly to avoid road hazards such as potholes, flooding or icy road surfaces.
In terms of the law, this states that you must be able to see out of all glass panels on the vehicle. Inadequately demisting or removal of ice and frost could result in your being responsible for subsequent damage. It could also invalidate or limit your insurance cover.
Beyond this, there is a real risk of damage to the glass panels if you improvise some method of removing ice without forethought.
Let’s look at the options available.
Scraping
Scrapers are things we pretty much all have, or have used at some time. Make sure the scraper is easy to find and preferably stored in the car.
Be wary of using tools not intended for this, such as painting tools or odd kitchen utensils. Make sure you have a scraper that is easy to hold and control and which will not scratch the glass surface. This last point isn’t just winter-season advice. As automotive glass – especially the windscreen – ages, it becomes more prone to water or melting ice smearing across the surface, instead of running away smoothly. This is caused by scratches, invisible to the naked eye, that accumulate with time. Using a poor quality scraper can make this much worse. Equally, pay attention to your wiper blades to make sure they are in good condition and not contributing to scratching. Final tip: a scraper with a long handle is easier and quicker to use than the discount versions.
Liquids
Most of use have used some sort of de-icing spray. The advantages are twofold. It makes it easier and faster to remove the ice and it also provides a limited time after application to prevent new frost forming on the windows, which is a common problem when it is really cold and damp. The better de-icer sprays will hold back ice formation long enough for the vehicle to heat up and prevent new ice forming.
Sprays can be aerosol or spray-bottle types, depending on cost. The reputable brands typically contain methanol in conjunction with other chemicals and will not mark or damage the vehicle’s bodywork. The home-brew version, using diluted vinegar, will also work but it also runs the risk of marking painted and metal surfaces.
Water
Used carefully, this can remove ice or snow quickly without scraping and keep the glass ice free long enough for the vehicle to heat up. The operative word is “carefully”.
Always use cold water. Using warm or hot water can aggravate hairline cracks in the glass and damage the weather seals around the glass. Use a container suitable for pouring – you don’t want to get wet while doing this! – and pour the water onto the bodywork above the glass panels, allowing it to run downwards. This avoids any extreme temperature difference between the water (usually 10 to 20 degrees C) and the iced glass that could be as much as 40 degrees colder.
In all this, the main thing is doing it properly and allowing for the time and effort involved. The last thing you need in adverse driving conditions is limited visibility.