It’s very common for condensation to form on the inside car windows. And if the weather’s cold enough, this condensation can freeze into ice.
In this post, we’ll explain what causes this condensation to form, why it’s a problem, and how to stop it from happening.
Why Does My Car Get Condensation Inside?
Condensation can form inside your car when there are different temperature and moisture levels inside and outside your car. When warm air meets your cold windscreen, any water vapour in the air can condense into windscreen fog. If the temperature’s low enough, this condensation can freeze into ice.
It’s common for windscreen condensation to build up during journeys. Your breath and your passengers’ breath is the culprit here. Human breath is warm and moist, and when it meets that cold windscreen, it can become moisture.
But condensation can also build up overnight. This is because the interior of your car is an enclosed space. Over a prolonged period of time, both temperature levels and moisture levels can build up. And when the temperature’s low, your windscreen’s going to be cold. So with that mix of a warm, moist car interior and a cold windscreen, you might find condensation inside your car on frosty winter mornings.
Why Is Windscreen Condensation Dangerous?
Windscreen condensation is a problem because it obstructs your view of the road. This isn’t just an inconvenience. It’s also illegal. Section 41D of the Road Traffic Act 1988 says that you must have a clear view of the road before you move off.
Whether it’s first thing on a cold winter morning, or having returned to your vehicle after popping into a shop, if you find your windscreen’s misted up, make sure you clear it before you set out.
There’s a few steps you can follow to demist your windscreen quickly. Read our guide to demisting your windscreen in rain and winter.
But if you want to stop your windscreen from misting up in the first place, there are a few things you can try.
How To Stop Your Windscreen From Misting Up in Winter
- Clean Your Car – Dirt and grime can give moisture something to cling to. So if you regularly clean your car inside and out, moisture will have a harder time taking hold, and you may see less condensation from on your windows.
- Cover Your Car – Get a winter cover for your car. It won’t stop moisture levels from building up on the inside, but it will protect your windscreen from the elements, meaning that condensation and ice is less likely to form overnight.
- Look For Leaks – A leak in the lining of your car’s doors, windows or sunroof can allow atmospheric moisture into your car’s interior. And as we’ve seen, when this builds up, it can lead to condensation and ice. Check your car in for a service and a trained mechanic might be able to spot and fix any leaks.
Safe Driving in Cold Weather
You’ll find lots of guides on our site to help you stay safe on the roads through the colder months of the year:
- How to demist your windscreen in rain and winter.
- Getting your car winter ready.
- Winter tyres – what are they and do you need them?
- Car won’t start in the cold, and other winter car issues.