How to Stop Condensation on Car Windows
Ellie Dyer-Brown, 30 days ago
5 min read
- Car ownership
- How to
FixMyCar provides tips and tricks for eliminating condensation.
Are you fed up of finding your car windows wet with condensation? It’s a common problem for motorists, and there are several things you can do to prevent it. This guide provides practical advice and a handy life hack to banish the moisture in your car for good.
Contents
What causes condensation in a car?
Do new cars have less condensation?
How to prevent condensation in a car
How to stop condensation on car windows overnight
How to clear away condensation
The dangers of driving with condensation on car windows
In a nutshell: You need to remove moisture from the air and keep your car ventilated to prevent condensation. You can do this by opening a window, switching on the aircon or blower, and putting a dehumidifier in your car.
What causes condensation in a car?
Condensation happens when warm air meets cooler air and condenses to create moisture. Your car windows are often at a different temperature than the air outside, which is why they get condensation on them.
Since the temperature drops overnight, you’re most likely to see condensation on your car windows first thing in the morning. Other things can cause it as well, such as:
Steam from hot food or drinks
Heat from your body (e.g. if you’ve just worked out)
Leaking doors, windows or vents
Coolant leaks
This guide explains how to diagnose leaks. If you think a leak is the reason for your car’s condensation, you’ll need to book a repair.
Do new cars have less condensation?
You’d think this would be the case since new cars have better insulation and tighter seals, but that doesn’t always work in their favour. They are better at trapping warm air, which leads to more moisture building up. You can counteract this by opening a window slightly to improve airflow.
How to prevent condensation in a car
Below are a few tricks to prevent condensation from forming in your car.
1. Use your air conditioning
Regularly using your car’s air conditioning system isn’t just beneficial for its health; it also prevents condensation. The aircon draws old, moisture-rich air out of the cabin, condenses it, and gets rid of the water in a controlled way. The less moisture in the air when you park up, the less condensation will form overnight.
Even if your car doesn’t have air conditioning, you can still use the blower to increase the airflow. Make sure you have the controls set to ‘fresh air’ rather than ‘recirculate’.
Helpful guides:
2. Focus on ventilation
Good ventilation is the most important thing to focus on when trying to reduce condensation. Regularly opening a window or door and letting fresh air flow through the vehicle will help to keep it dry.
3. Check for leaks
If your car always has lots of condensation, rainwater might be seeping in through door seals, creating damp patches. The heater is another common place where cars get leaks. Look around and see if you can spot areas where the seals might need replacing.
4. Keep your windows clean
It’s easier for water to stick to dirty windows, so try to keep the glass clean. This will also help the demisters work better.
5. Open the windows when you have hot food or drinks
The steam from hot food and drinks will create condensation in your car. Crack open a window or use your air conditioning to remove excess moisture.
6. Maintain cabin air filters
Regular maintenance of your cabin air filter is important for good ventilation and airflow. It should be replaced roughly every 10,000 miles; this is often done during a full service. You can find the correct replacement interval for your model in the owner’s manual.
How to stop condensation on car windows overnight
1. Don’t leave wet items in your car
Wet items like raincoats and umbrellas create humidity, which may cause condensation. Whether you have a bag of sweaty gym clothes in the boot or a wet coat after being caught in a downpour, remember to take it out at the end of the day.
2. Keep your car covered overnight
If you keep your car in a garage overnight, use a lightweight, breathable cover to prevent condensation.
3. Get a dehumidifier
Dehumidifiers work by taking the moisture out of the air. You can get them in varying sizes, and some are designed specifically for cars.
4. Use silica gel pellets
You can buy silica gel pellets online. They often come in a bag or packet you can leave in your car to draw moisture out of the air.
5. Put cat litter in tights
This DIY life hack will save you money if you already have a bag of cat litter at home. Fill a sock or tights with the litter to create your own dehumidifier, then leave it in your car. It will absorb moisture just like silica pellets. When you think it has absorbed as much liquid as possible, replace it with a fresh batch.
How to clear away condensation
Foggy windows are a safety hazard, so clear them thoroughly before driving anywhere. Follow these steps to get rid of the condensation:
Turn the heater on and switch it to the cool setting. Direct the air at the windscreen if possible.
Use the air conditioning or open a window to get the air circulating.
Gradually increase the temperature as the condensation clears.
Use the windscreen and rear window demisters (if your car has them) to speed up the process.
The dangers of driving with condensation on car windows
Condensation on your car windows is more than an inconvenience. It obscures your view of the road, putting the safety of you, your passengers and other road users at risk.
The dangers include:
Impaired visibility
Increased risk of collision
Delayed reaction time
Potential legal consequences
The law
The Highway Code states that windows and windscreens must be kept clean and free of obstructions. Similarly, the Road Traffic Act says you must have a clear view of the road ahead.
If you’re involved in an accident or the police catch you driving with windows that aren’t clear, you could be penalised. You’d likely get an MS60 conviction, resulting in three points on your licence and a fine.
Read about common driving offences and penalties.
How to dehumidify a car and remove damp
A damp car interior is something you want to avoid because it can lead to problems with condensation and mould. However, if the inside of your car is already quite damp, we've got some tips for drying it out.
Remove excess moisture
Use a dry cloth to wipe away excess moisture from surfaces. If the upholstery is damp, you could use a hairdryer on it if you have an extension cord that will reach the car.
Air it out
Ventilation is the best way to remove damp and prevent mould. On a warm, sunny day with no chance of rain, open the doors and windows for as long as possible (without leaving the car unattended) to give it time to dry.
Use a dehumidifier bag
Once you’ve removed as much dampness as possible using the tips above, the final thing to do is buy a dehumidifier bag and leave it in your car to get the remaining moisture out of the air.
How to get rid of mould in your car
Mould is unpleasant, but it’s not too hard to get rid of. You’ll need a few household cleaning products and some elbow grease. We recommend wearing a mask and rubber gloves to ensure you don’t breathe in mould spores, which are bad for your health.
Clean your car out, removing any rubbish and belongings.
Hoover the upholstery and carpets to get rid of mould spores.
Mix eight parts distilled white vinegar to two parts water in a spray bottle. White vinegar not only removes mould but also stops it from coming back.
Test the cleaning solution in an area that’s out of sight, then spray the mixture onto mouldy areas. Make sure they are saturated, and use a scrubbing brush to rub the mixture in.
Air out your car to get rid of the vinegar smell. When it’s dry, sprinkle baking powder on the areas you have treated, leave it for a few minutes, and then hoover it.
Here are some extra tips for cleaning your car.
What causes mould in your car?
The two leading causes of mould are dampness and lack of fresh air. The best way to prevent it is to follow our advice about reducing condensation and dehumidifying your car.
Looking for affordable car repairs or maintenance? FixMyCar can help you find the right garage at the right price.
If you found this guide helpful, you might also like:
Written by Ellie
Ellie is FixMyCar's Content Writer. She has over three years of experience writing about cars and regularly collaborates with automotive experts to provide trustworthy advice for drivers in a language they understand. Her work has been featured in Yahoo! Finance, iNews, The Daily Express and The Sun. She has a BA in English literature and an MA in creative writing from Durham University. Outside of work, Ellie follows F1 and eagerly awaits Ferrari's next era of dominance in the sport. She drives a Suzuki Swift.