The quickest safe way to de-ice a windscreen is to start the engine with the heater blowing on the screen, spray a de-icer such as SOFT99 Glaco Deicer on the outside, then clear the softened ice gently with the wipers switched off. Our screen wash range has the winter mixes that keep the washers working.
What is the quickest safe way to de-ice a windscreen?
Heat from inside and de-icer from outside, working together. The heater warms the glass slowly and evenly from the cabin side while the de-icer softens the ice on top, so a few minutes later it slides off with a soft scraper or a gloved hand instead of having to be chipped away.
How do you de-ice a windscreen step by step?
Give yourself ten minutes on frosty mornings and do it in this order.
- Start the car and stay with it: turn the heater to the windscreen setting with the fan on full, and switch on the heated screen if your car has one.
- Leave the wipers off: check the stalk is off before you start, so frozen blades do not try to move.
- Spray the de-icer: cover the glass from the top down, including the edges where ice is thickest.
- Wait a minute: let the de-icer and the warm air soften the ice.
- Clear the softened ice: push it off with a plastic scraper held flat, working from the top down, with no hard chipping.
- Free the wipers last: lift the blades gently once the screen is clear and check the rubber has not stuck or split.
- Clear every window: do the side windows, mirrors, lights and number plate as well, so you can see and be seen.
Why should you never pour hot water on a frozen windscreen?
Because a sudden change in temperature can crack the glass, especially if there is already a small chip, and the water you pour on refreezes on the screen and the ground around the car within minutes. Lukewarm water is not much safer for the same reasons. Heat from the inside and a proper de-icer are slower by a minute or two and far kinder to the glass.
Should you use the wipers to clear ice?
No. Wiper blades frozen to the glass can tear their rubber edge or strain the wiper motor if you switch them on, and dragging them over ice blunts them. Clear the screen first, then free the blades by hand and check them before you set off.
What helps to de-ice a windscreen?
A de-icer for the morning, a coating that makes the glass harder to freeze, and a washer bottle that does not freeze.
Thaws ice and snow frozen onto glass and leaves a hydrophobic coating that makes it harder for the glass to freeze again. Hold it 15 to 20cm from the screen and switch the trigger between a mist and a precise spray.
A water-repellent coating for windows and glass wing mirrors that also makes the glass slower to freeze over on frosty mornings. Apply it to clean, dry glass before the cold weather sets in.
How do you stop a windscreen freezing overnight?
Coat the glass before the frosts arrive and cover it when a hard frost is forecast. A hydrophobic coating such as Glaco Roll On or the coating Glaco Deicer leaves behind makes it harder for frost to bond to the glass, so less ice forms and what does form comes away more easily. A windscreen cover held in by the doors does the rest on the coldest nights.
Keep the inside of the screen clean as well. A film on the inside glass holds moisture and fogs up as the car warms, which slows the whole job down. Our guide to stopping car windows steaming up covers the inside of the car.
How do you stop the screen wash freezing?
Use a concentrate at its winter ratio and never top it up with plain water. A frozen washer bottle leaves you with a salty, smeared screen and no way to clear it on the move. These are the screen washes we stock for winter.
A ceramic concentrate mixed 1:5 for winter and 1:10 for summer, which leaves rain, sleet and snow beading on the glass.
An SiO2 ceramic-infused concentrate used half and half with water all year round and neat in severe winter, in a 5 litre size.
A concentrated washer fluid additive you dilute to the strength you need, in a 500ml bottle.
What should you clean the glass with once the ice has gone?
A streak-free glass cleaner and a dry microfibre, once the car is warm and the glass is dry. Salt and grit from the de-icing leave a film that smears in low winter sun, and a hydrophobic cleaner tops up the coating at the same time.
A streak-free glass cleaner that leaves a water-repellent layer in one step, on wet or dry glass, coated or not.
Common questions
Can you use a bank card to scrape ice?
We would not. It snaps easily, does little against thick ice and puts your hand close to the glass. A plastic scraper held flat, after the de-icer has softened the ice, is quicker and safer.
Is it worth leaving the car to warm up?
Only for as long as it takes to clear the glass, and only with you in the car. Warm air on the inside of the screen makes the de-icing easier and clears the misting at the same time, but on a public road the law does not allow you to leave the engine running unnecessarily while the car is stationary, or to leave it running unattended at all. Let the de-icer and a scraper do most of the work, and set off once every window is clear.
Why does my windscreen smear after de-icing?
Salt, grit and de-icer residue mix with the water as the glass thaws. Clean the screen once it is dry, and check the wiper blades, which take a beating in winter. Our guide to why a windscreen smears goes through every cause.
Does rain repellent help in winter?
Yes. A coated screen sheds rain and slush more easily, and Glaco Roll On makes the glass slower to freeze over on frosty mornings.
For the rest of the car through the cold months, see our routine for protecting your car in winter.
Need help choosing?
Tell our team what you drive and where it is parked overnight, and we will put together a winter glass kit. You can also browse our glass sealant and glass care ranges.
