Your car's windscreen isn’t just a piece of glass to keep the wind and rain out.
- A clean, clear windscreen is essential for good vision when driving.
- A bonded windscreen is an integral part of the vehicle body, contributing towards strength and stiffness.
Whether it's a foggy windscreen or a small crack, here’s how to stop it becoming dangerous.
In this article
Best way to clean your windscreen - step by step
There are different ways to clean your windscreen and you might even have seen some “hacks” online. But the best way is this classic method which uses glass cleaner and 2 microfibre cloths.
Step 1 - Prepare the windscreen
- Carefully lift up your windscreen wipers away from the glass. (On some cars, you’ll need to use the “wiper maintenance” mode rather than lifting. Info will be in the handbook.)
- If your windscreen’s very dirty, wash it first with water and a brush.
- Make sure the windscreen is dry afterwards.
Step 2 - Use glass cleaner
- Spray half your windscreen with alcohol-based glass cleaner.
- Avoid ammonia-based cleaners which can cause damage.
Step 3 - Wipe with a cloth
- Use a clean microfibre cloth to wipe your windscreen in long, smooth strokes.
- You can wipe top to bottom and side to side to make sure no spots are missed.
Step 4 - Repeat
- Clean the other half of your windscreen by spraying the other side and cleaning with a cloth.
Step 5 - Clean the wipers
- This is a really important step that’s often overlooked.
- Give the rubber of the windscreen wipers a good clean with screenwash to remove dirt and debris.
- This will make them work much better and could extend their life.
Step 6 - Buff the glass
- Buff the glass with a second clean microfibre cloth.
Step 7 - Clean the inside
- Repeat the cleaning steps for the inside of your windscreen.
- Use clean cloths to avoid smears.
- Spray the cleaner onto the cloth instead of the glass to avoid getting it on your dashboard.
Cleaning the inside of your windscreen
It’s just as important to clean the inside of your windscreen as the outside.
Over time, chemicals from leathers, plastics and vinyls inside your car are released in a process called “off-gassing”. These gases can make the inside of your windscreen greasy.
Can you clean your windscreen with vinegar?
You can add a small amount of vinegar and methylated spirits to water to make an effective cleaning solution. The vinegar cleans well and the alcohol makes the solution evaporate quickly, reducing smears.
But both of these chemicals can be unpleasant smelling. Plus, getting the ratio perfect is a bit hit and miss. When you add in the cost and preparation time, you’re no better off that if you use a proper glass cleaner.
Shop-bought glass cleaner has the added benefit of a pleasant perfume in most cases. It’s particularly welcome when cleaning inside the windows.
How to demist your windscreen
It's common to find your windscreen misted up when you get into a cold car. It's important to clear it thoroughly. Here's some tips:
- Look for a windscreen demister button in your car that'll direct maximum airflow to the windscreen to clear it quickly.
- Some cars have an electrically-heated front windscreen with very fine wire heating elements embedded in the glass.
- Air-con's not just for summer - it helps to dry the air in the car too, so helps clear a misted windscreen.
- Keep a microfibre cloth in the car to wipe the screen if it mists over again while you're driving.
For rear screens and wing mirrors, try these steps:
- Rear screens have electrical heating elements running across them to clear mist quickly.
- You might be lucky and have heated mirrors. If not, wipe your mirrors with a cloth.
- You could also try demisting sprays, which claim to leave your windshield fog free for a few weeks.
For foggy glasses, wipe them with a cloth (preferably a microfibre lens cloth) to get rid of all smears. There are also anti-fog lenses available, and are offered by most opticians.
How to defrost your windscreen
On frosty days, it’s important to make sure that your windscreen is completely defrosted before you try to drive. It’s not enough just to clear a small patch to see through.
- Make sure your wipers aren’t on before you switch on the engine, in case they’re frozen to the glass.
- Turn on the engine and turn on the warm air blower. You can also use the aircon to remove moisture inside the car.
- Turn on the rear-windscreen heater and heated mirrors if you have them.
- Use a scraper and de-icer on your windscreen while you wait for the car to heat up.
Learn more about how to defrost a car windscreen with our step-by-step video.
How to avoid windscreen glare
The glare of light from the sun or passing cars can distract you when you’re driving.
The best way to reduce glare is to make sure that your windscreen is clean inside and out, and free from any cracks or stone chips. Cleaning your windscreen and wiper blades will help get rid of smears.
- Even if you're not a smoker, a hazy film will build up on the inside of the glass, so you need to clean it regularly.
- Scratches, abrasions and chips on the outside can make dazzle from the sun worse too.
- New blades clear the screen more effectively and help reduce the dazzling effect of the sun – try to renew them once a year.
- Keep the screen-wash topped up using a good quality screen-wash additive to help clean the screen all year round as well as reduce freezing in cold weather.
If you wear glasses without glare protection, you could suffer from headaches or eye strain when you drive. Glare-resistant lenses are available from most opticians and are ideal for frequent drivers. You can also look out for anti-glare driving glasses and driving sunglasses.
Dealing with windscreen damage
Damage to the windscreen can obstruct your vision. High mileage vehicles that have spent a lot of time on the motorway will probably have thousands of tiny chips or “pits” in the windscreen. They're very difficult to see in normal light but you’ll see them at night, when light from oncoming vehicles is refracted. It looks very similar to a very dirty windscreen. The only way to fix this is to replace the screen.
Small windscreen chips or cracks can be easily repaired using specially-developed clear plastic resins with the same optical properties as glass. But if you ignore them, they can grow. Once the damage is bigger, you're more likely to have to pay out for a new windscreen.
You can find out more about windscreen chips and cracks in our article on windscreen damage and insurance.
Dangling objects from a rear-view mirror
Wondering if it's illegal to hang something from your rear-view mirror? You may be breaking the law if it obscures your vision.
When we spot-checked in a survey, 5% of drivers - equivalent to 1.5 million drivers at the time - had things dangling from their rear-view mirrors.*
The survey of more than 2,000 vehicles on motorways found that 1 in 20 vehicles had items dangling from their rear-view mirror which could create a blind-spot. The number 1 item was a green scented tree which seemed to be favoured by van and pick-up truck drivers.
The most bizarre and dangerous item was a silver CD. In the morning sunlight, it had the extra danger of dazzling other drivers with the reflection.
The top 5 items spotted dangling in the windscreen
- Air fresheners (mainly trees)
- Teddy bears (from small to 1 foot in length)
- Miniature footballs
- Beads and rosary beads
- Coats of arms (mainly football clubs)
Can your windscreen fail your MOT?
Regulations tell you to have a full view of the road and traffic ahead. If the driver's vision is impaired, technically the car could fail an MOT.
In your MOT, you shouldn't have a windscreen sticker, chip, crack or other obstruction covering more than 10mm wide in the area above the steering column, called ‘zone-A’.
In the rest of your windscreen, the obstruction shouldn’t be more than 40mm wide. Windscreen stickers or objects hanging from the rear view mirror could also be a problem if they're too big or poorly positioned. And that includes fuzzy dice. But it's worth remembering that so could dash-mounted tech like phones, sat-nav or dash-cams.
Your car can fail the MOT if a wiper blade is loose or missing. You can also fail if the wipers don't clear the windscreen properly to give you a clear view of the road to the left and right sides of the vehicle, as well as to the front.
Wipers that judder, make a noise, leave bands of rain or unwashed margins should be replaced.
What are the penalties if your windscreen isn't clear?
Driving safely means making sure that your line of vision is kept clear. If your vision is obscured, you might not be able to see the road ahead properly and it could even create a blind spot.
The Highway Code says "windscreens and windows MUST be kept clean and free from obstructions to vision".
Failing to keep your vision free from obstruction could:
- Land you a fine and 3 penalty points.
- Mean you're held responsible if you're in an accident.
- Cause your car to fail its MOT.
The penalty code covers "causing or likely to cause danger by reason of use of unsuitable vehicle or using a vehicle with parts or accessories (excluding brakes, steering or tyres) in a dangerous condition".
*(AA Spot-check survey of 2,000 vehicles was carried out on motorways on Monday 5 September, 2011)