Why you should never de-ice your car using hot water – and what to do instead

The de-icing mistakes we're all making. (Getty)
The de-icing mistakes we're all making. (Getty) (Getty Images/iStockphoto)

Yahoo Life’s editors are committed to independently selecting wonderful products at great prices for you. We may receive a share from purchases made via links on this page. Pricing and availability are subject to change.

While a wintry frost might look Insta-pretty, frozen windscreens are less ideal, particularly as you can guarantee you’ll have to de-ice them on a day when you’re also running late.

In the search for a super-speedy solution, many of us will turn to the trusty kettle and fling boiling water all over the glass.

But, turns out that’s not a great idea, as it could actually crack your screen.

"Too many people still take the risk of pouring boiling water on their windscreens as a quick fix to their ice problems," explains Keith Hawes, director of Nationwide Vehicle Contracts.

"The issue with this method is that it can actually cause your windscreen to shatter, particularly if you have tiny nicks and chips."

Hawes says a further popular de-icing suggestion to use a plastic bag filled with warm water to clear the screen comes with a similar risk.

Read more: This small but mighty heater plug is on sale

Have we been de-icing our cars all wrong? (Getty Images)
Have we been de-icing our cars all wrong? (Getty Images) (Getty)

Turns out the quest to remove ice from car windscreens quickly on wintry mornings can have some pretty costly impacts.

Research from MORE THAN has revealed one in five (20%) drivers under the age 35 have damaged their car’s windscreen when clearing frost, costing them an average of £143 to repair or replace it as a result.

Thankfully there are ways to effectively, quickly and safely remove frost from your screen without causing damage or forking out for an expensive de-icer.

5 de-icing mistakes we're all making

Using boiling water

Research by Halfords, which polled 1,600 motorists about their winter car habits, revealed that half of motorists have used a kettle of hot water to defrost their car windscreen.

But that could be a costly mistake as the sudden warmth hitting your windscreen in chilly temperatures could lead to the glass cracking.

Just leaving it

Sure, it’s tempting to stick the heater on full blast and drive off hoping the screen will soon clear, but that’s a move that could land you in trouble.

According to the Highway Code, “windows and windscreens must be kept clean and free of obstructions to vision”.

During the icy winter months, this is particularly relevant and you must clear the ice (or snow) from all of your windows, as well as both the front and rear windscreen, before driving.

"Only clearing ice or snow from part of your windscreen, known as ‘portholing’, can lead to up to three points on your licence, and a £60 fine," explains Hawes.

Read more: 7 surprising tricks to stay warm in bed this winter

"By law, every glass panel must allow full vision, and you must have a clear view of the road from all angles before you set off."

The same goes for clearing the condensation that forms inside the car.

Don’t be tempted to leave your car to defrost while you head back in the warm either as you’ll be risking a fine of £20 and three penalty points for leaving your car to defrost while the engine is idling.

The law says if your car's engine is running, you need to be “in control” of it, which likely rules out you being in your house in the warm while your car ticks over outside.

And, of course, if you’re busy grabbing a cuppa inside, your car could also be an easy target for thieves.

Waiting in the car for the screen to warm up isn't environmentally friendly. (Getty Images)
Waiting in the car for the screen to warm up isn't environmentally friendly. (Getty Images) (Getty)

Sticking on the heater and waiting for it to clear

Hands up who hasn't been paying attention to the climate change warnings? While ultimately effective, this is the least environmentally friendly option thanks to extra fuel you’ll use and the extra pollution you'll cause.

Starting the wipers

Tempting though it might be to speed along the process along by using your wipers to help shift the ice, starting up wipers that are frozen to the windscreen or jammed by snow could cause damage to the mechanism.

Using a credit card

Halfords found that over a third (35%) of drivers have admitted to using a bank card to scrape ice from their windscreen. While it may seem like a good idea, using anything other than a proper ice scraper risks scratching the glass.

Of course it could also cause your precious card to snap too, rendering you card-less, and potentially therefore cash-less.

The best (and safest) ways to de-ice your car

Use a windscreen scraper or de-icer

Both offer the easiest and safest method to free your car of frost.

Make a DIY de-icer

While de-icers are effective, there are some more cash and environmentally-friendly ways to remove ice from your screen.

One easy method is to mix up a solution of water with a teaspoon of salt, before pouring it over any frozen areas.

Use this sparingly, however, as salt could cause damage to the windscreen and avoid hitting the paintwork as it is also corrosive.

Mixing up three parts of vinegar to one part of water will also do the trick, but could be a little on the smelly side.

Meanwhile, Hawes suggests an alternative solution of mixing water with rubbing alcohol which you can get from any pharmacy.

Mix one part water with two parts rubbing alcohol and fill the spray bottle with the solution. This can then be sprayed on your windscreen to melt the ice.

"The really great part is that this solution will not freeze, as rubbing alcohol has a freezing point of around -88 degrees celsius, which means the bottle can be kept in your car until next time," he says.

"You can also use hand sanitiser to remove the frost from your keyholes if necessary."

How to properly de-ice your car [Photo: Getty]
How to properly de-ice your car [Photo: Getty] (Getty)

Read more: Best mattress deals 2022 UK - including John Lewis, Emma, Simba and more

Prep the night before

If the temperature has dropped and you suspect it will be an icy morning when you wake, you can plan ahead to stop the frost on your car windows.

"You can achieve this by using an old towel and covering your windscreen," advises Hawes. "Trap the top two corners of the towel in the driver and passenger doors to secure before the temperature drops the night before travelling."

Doing this means your towel will take the brunt of the ice, meaning your windscreen will be clear when it is removed. Get those dusty beach towels out and put them to good use!

Put plastic bags on your mirrors pre-frost

To prevent being fined due to icy mirrors, Hawes recommends putting plastic shopping bags over your mirrors the night before and securing with elastic bands.

"When you remove the bags in the morning the mirrors should be free of ice," he adds.

Shop top-rated winter car products

RevHeads Ice Scraper | £10.99 from Amazon

FREESOO Windscreen Frost Protector Car Snow Cover | £7.99 from Amazon

AA Winter Car Kit | £18.23 from Amazon

Advertisement