How to de-ice your car windscreen

Knowing how to de-frost your car windscreen and prevent it getting iced up can save you time and hassle on cold winter days.

It’s essential that you don’t drive off until you have clear visibility through your car windscreen and windows. It may be tempting to set off as soon as you can see through a small gap in your windscreen - also known as ‘portholing’. However, this is not only unsafe, but it could also cost you a fine and penalty points on your licence[1].

Here’s how to de-ice your windscreen and get on the road quickly and safely.

Use a scraper

This is a simple, but usually effective first step. Use a scraper or a plastic edge to remove ice but be careful along the edges of your windows and windscreen, to avoid damaging seals. If you haven’t got a scraper, you can use a spatula or even a credit card, as long as you’re careful not to damage the magnetic strip on the back it[2].

To avoid getting cold and icy hands when scraping your windows, it’s always a good idea to put on some gloves.

Turn on the heater

Turn on your car heater, ensuring the heat is directed at the windscreen and the windows. The RAC[3] recommends starting the heater cold, then slowly increasing the temperature, to avoid overloading the cabin with hot, ‘wet’ air. Using the air-con can keep the atmosphere inside dry. 

Don’t leave the car idling while it’s warming up. By leaving it unattended, you could put your car at risk of theft and could also be breaking the law.

Use your car’s technology

If you own a modern car with remote heating and defrosting, then make use of these nice features to help de-frost the windows.

Don’t pour boiling water on your windscreen

Pouring boiling water on your car windows is never a good idea, as the sudden temperature change can cause the glass to crack.

Even using lukewarm water is best avoided. On particularly cold days, the water could quickly freeze[4], making it harder to de-frost your car windscreen.

Get rid of any snow

Remove any snow from your roof before stating the car so it doesn’t blow off when you’re driving. This could be a dangerous distraction to your or other road users.

Seek advice you can trust

There are many suggestions online to defrost car windscreens and windows, but not all of them are reliable, so make sure you know and trust the source of the advice you’re reading.

One common but unreliable hack that can be found online is to cut a potato in half and rub it over the windscreen the night before. This is because potatoes contain glycerol, a substance which is found in anti-freeze. But, while you might find a less icy windscreen in the morning, you’ll also probably find it is smeared, which can actually impact your visibility[5].

Be careful with your wipers

It can be tempting to use your wipers to help clear the ice, but you could end up damaging them if you turn them on and they’re frozen stuck.

For the same reason, make sure your wipers aren't on before you start your car.

Plan ahead

You may be able to avoid your car windows getting covered in ice in the first place. For example, if you have a garage that you haven’t filled with other gear, then it’s a good idea to clear it out so you can park your car inside on cold nights.

If you don’t have a garage - or are using it for something else and can’t clear up the space quickly - then you can also cover your windscreen to stop it getting icy, using a piece of cardboard or an anti-frost windscreen cover, which you can buy cheaply online. Covering it up every night is a simple but effective way to keep your windscreen from icing up.

However you go about it, the important thing is to ensure your windows are completely clear before setting off. This will help you stay safe on the road, especially when driving in wintry conditions.

[1] https://www.rac.co.uk/business/news-advice/frosty-windscreens
[2] https://www.lookers.co.uk/blog/how-to-remove-ice-from-your-windscreen-without-a-scraper
[3] https://www.rac.co.uk/drive/advice/winter-driving/how-to-demist-your-windscreen-in-double-quick-time/
[4] https://www.holtsauto.com/prestone/news/ever-ok-use-warm-water-defrost-windscreen/ 
[5] https://www.theaa.com/driving-advice/seasonal/defrosting-car-windscreen