How to demist your windscreen quickly

Thursday 24th October 2019

Whether you’re rushing to get to work, dropping the kids off on the school-run or simply have errands to run, getting in the car to a fogged-up windscreen is never ideal. There goes a good five minutes of your time waiting for it to clear so you can be on your way safely…

But what if there was a way to clear the mist quickly? Learn how to stop car windows from fogging up in winter, as well as preventative tips, from our helpful guide.

Why does my windscreen mist up?

Windscreens and windows typically mist up due to the water vapour in the atmosphere. When you enter a vehicle, your body heat and breath are likely to heat up the air in the atmosphere, which increases the amount of moisture in the air. This warm moisture is then condensed against cold windows and windscreens in the vehicle as it comes into contact with them, and forms as a mist.

How to demist windscreens

Knowing how to demist a car quickly, especially when you’re in a rush in the chillier months, is not only important for allowing you to get on with your day, but from a safety aspect, too. UK law states that you must be able to see out of every window in your car before driving – so having a misted windscreen can result in a fine, as you’re putting both yours and others’ lives in danger.

• Heater – the most common go-to strategy to de-mist car windows is whacking up the heat on full blast and hoping for the best. However, knowing how to use your heater properly can be helpful for de-misting windows quickly. Begin by releasing cold air and gradually increase the temperature as the air dehumidifies– as circulating hot air to begin with releases ‘wet’ air into the vehicle, which delays demisting. Also, remember to direct the vents towards the windscreen and windows as opposed to the driver or passenger.
• Air Con – despite popular belief, using your air con will help. The air con can be used simultaneously with the heater, as the hot air will partly dry the glass through evaporation, but begin to condense on the glass again when cooled down. However, the simultaneous conditioned air will ensure the atmosphere inside the vehicle stays dry. Plus, using your air conditioning in winter (when windscreens are more likely to mist up) is beneficial to keep it working effectively all year round, too. Unsure if your air con is working efficiently? Our Air Con De-Mist or Air Con Clean services can ensure it’s working optimally, allowing you to clear your windscreen as quickly as possible.
• Climate control – does your car have a climate control system? If so, this is the perfect time to use it. Check to see if there is a setting for demisting windscreens and this will automatically alter your temperature in the car to achieve the best results.
• Windows – dependent on the temperature outside, you can also demist your windscreen by opening your windows. The dry and cold air outside can reduce the amount of water vapour in the atmosphere within the vehicle and help clear the windows and windscreen faster. This is a handy tip to use when you’re already driving and your windscreen begins to mist up! Of course, if snow and ice are the reasons your windows are obscured, do not attempt to open the windows – as, if they have frozen, this can break and crack the glass, as well as potentially damaging the window mechanism.

How to prevent car glass from fogging

Now you know how to demist car windows quickly, it might be useful to find out some of our tips on how to prevent car glass from fogging up in the first place:

• Dehumidifier box – purchasing a small dehumidifier box, would help absorb the moisture in the air before it hits your windscreen – protecting the screen from misting as quickly.
• Windscreen shields – designed to protect against sun, snow and ice build-up, a windscreen shield will cover your car windscreen, which can be useful for both summer and winter, reflecting the sun’s rays - keeping your car cool or preventing your car's glass from fogging.
• Clean windows – if your windows are clean, they’re less likely to mist up – that’s referring to both on the outside and inside of the vehicle. Using soap, or shaving foam, creates suds which, when then cleaned off correctly, leaves a protective layer that can prevent the glass from fogging up. However, this is only a temporary fix – and needs to be reapplied regularly, but a windscreen cleaned in this way is less likely to fog-up.

Learning how to demist windscreens and windows quickly can be very time-efficient, and can also keep you safe while driving on the roads. For any more motoring advice, get in touch with one of our expert team or locate your nearest Formula One Autocentre today.