Drivers warned never to use popular 'hack' to clear windscreens

Drivers are being warned that they could risk damaging their car this winter all thanks to a common "hack". With the colder months now here, many motorists will be waiting longer to de-fog or de-ice their cars.

But in a warning from Windscreen Wipers, with more cold frosty weather on the horizon, drivers need to stop falling for online hacks. One of these is using water - and it's not just hot they're worried about. The experts caution: "Using water of any temperature to de-ice windscreens is not advised. Hot water will cause the glass to expand, which can result in it cracking or even shattering, and cold water can freeze on top of existing ice and frost. Both methods can damage your windscreen, sometimes beyond repair."

Because of this, windscreen washer fluid is designed to be used in freezing temperatures. The solution lowers the freezing point of the fluid so you can safely clear your windscreen while driving and not damage your wipers or the windscreen, the experts explain.

Even rubbing hot water in a sandwich bag on the windscreen to quickly remove frost can cause damage and small cracks in the glass which may not be noticeable until it's too late. Another de-icing hack they warn against is rubbing a potato on the windscreen to prevent freezing overnight. In fact, smearing anything on windscreens is a faux pas for drivers they say as this can leave debris on the screen and limit visibility.

Instead, you should use the car air-con to de-mist windows and whilst you wait, you can scrape off any snow and ice. Do allow the air-con to work efficiently, you need to turn on the car's heating on a low setting and gradually build up to a higher temperature, this will prevent the windows from fogging up even more. Then turn on the air-con to remove moisture from the air. if you don’t have working air-con, open the windows slightly for the same effect.

Experts at AA, back up this method stating: "If you use hot water for the ice on your car, you run the real risk of damaging your windscreen. Glass expands quickly when hot or even warm water touches it. But it'll contract quickly too as it cools down in the cold air. That flexing can make the glass crack even if you're using lukewarm water – especially if it had small chips or cracks already."

As well as telling people to not use water - cold or warm - they say that sadly, "not everyone bothers to clear all the ice off before they drive off, instead leaving just enough of a window to see through. This is known as 'portholing' and could get you in trouble with the police if you're caught driving dangerously."