How to measure tyre tread depth UK
The only portion of your vehicle that makes touch with the road is the tyres. As a result, the state of your tyres is critical to your safety.
It is required by law that your tyres have a minimum tread depth. Here you may learn about the law and how to check your tyres.
Car tyre tread checking
We'll talk about
- Tread depth that is permissible in a legal tyre
- How to Measure the Depth of Tread
- When should you change your tyres?
- The dangers of worn tyres are caused by tyre wear.
- Accidents and worn tyres are two of the most common causes of tyre failure.
- Other tyre regulations
- Tyre inflation pressure
What is the legal tread depth for a tyre?
Each type of vehicle has a different legal minimum tyre tread depth.
- Vehicle class
- Tread depth minimum
- Cars
- Vehicles for transporting goods (up to 3,500kg)
- 3.500kg trailers and caravans
A continuous band in the centre 3/4 of the tread and around the full circumference of the tyre must be at least 1.6mm thick.
The majority of larger vehicles
A continuous band of at least 1.0mm over at least 3/4 of the tread's width and around the full circumference is required. In the remaining quarter, the original tread pattern must be visible.
Motorcycles with a displacement of 50cc or more
A continuous band of at least 1.0mm over at least 3/4 of the tread's width and around the full circumference is required. In the remaining quarter, the original tread pattern must be visible.
Motorcycles and mopeds with engines under 50cc
The tread pattern from the original must be visible.
Checking the depth of your tread
You can check your tyre tread in a number of different methods to ensure that they aren't worn and that they satisfy the legal minimum tread depth. If you think you need replacement or emergency tyre repair, let professional check it for you.
Indicators of tread wear
Looking for tread wear indications is the simplest approach to check whether your tyre tread is legal. Small bars, about 5mm broad, are frequently built into the base of the tyre's major grooves.
If the top of the wear indicator is level with the tyre tread, your tyres have surpassed the legal limit of 1.6mm.
When tyres have worn this level of wear, they must be changed.
Gauges for tyres
Using a calibrated tyre gauge is the best way to test your tyres. These are available in a variety of formats, ranging from digital gauges to laminated cards with coloured indicators.
To use, insert the gauge into the groove of the tyre.
The gauge will tell you how close you are to attaining the vehicle's specified minimum depth.
Check the tyre tread on a frequent basis and in various locations across the tyre to keep an eye out for worn tyres and early signs of uneven wear.
The twenty pence test
If your tyres don't have treadwear indications or a gauge, you can do the 20p tyre test to check them. A 20p coin's outside rim is a little about 3mm broad.
Place a 20p coin in the tread grooves of your tyre.
If the outer rim of the coin is obscured, your tyre tread depth is well beyond the legal minimum.
If you can see part of the coin's rim, it's time to use a proper tyre tread depth gauge to check your tyres more thoroughly.
When are your tyres due for a change?
Once your tyre tread depth reaches 3mm, you should check it more frequently. Replace tyres before the tread wears to less than 2mm.
As autumn and winter approach, it's more necessary to change your tyres. It's preferable to acquire new tyres before winter than to suffer through the cold and wet with tread depths approaching the legal minimum.
Before your front tyres wear out, you should get around 20,000 miles out of them, and about 40,000 miles out of your back tyres.
More information on tyres can be found here:
- How to Change a Flat tyre Safely
- Learn how long tyres last.
- What are the reasons of tyre wear?
Tyres will wear down over time, but certain conditions can speed up the process.
Aggressive cornering and braking contribute to increased wear.
Position - The tyres on the driven wheels will wear out faster, especially on front-wheel-drive cars, which must also handle steering.
Speed - Driving at high speeds raises the temperature and wear on the vehicle.
Excessive load, as well as vehicle weight, increases wear. Tyres on heavier vehicles will wear out more quickly.
Underinflation (due to increased bending and heating) and overinflation (because to reduced contact area) can both result in greater wear.
Wheel alignment is important, and if suspension components like shock absorbers are worn, tyres will wear rapidly and unevenly.
Using a tread gauge to inspect the tyre
The dangers of driving on a tyre with a low tread depth
Driving on tyres with less tread than the legal maximum is both dangerous and unlawful. Driving on bald tyres, where the tread has completely worn away, is significantly worse.
The following are some of the dangers of driving on worn tyres:
- On wet roads, there is less grip.
- Stopping distances are longer.
- There's a higher chance of aquaplaning.
- On icy or snowy roads, there is less traction.
- Punctures are more likely, which might result in a rapid explosion.
You'll have improved road grip and shorter stopping distance if you change your tyres as the tread wears down. Your steering wheel may shake or tremble due to worn tyres or flat patches.
What if I get into an accident while driving on tyres that are unlawful or dangerous?
Any insurance claim you submit may be invalidated if you're in an accident and your tyres don't match the legal minimum specifications. You could be charged with operating a vehicle in a dangerous condition if you drive with risky tyres that are worn or bald.
You might face a fine of up to £2,500 as well as three points on your licence. And that's only for a single tyre. You might face a £10,000 fine and 12 points if all four tyres are determined to be unsafe.
Other legal tyre specifications
There are two unique standards for legal tyres because they play such an important role.
1. Tyres must be fit for purpose and free of faults that could harm the road or put people in danger.
Tyres must not have the following characteristics in order to be considered "fit for purpose":
- Any lumps, bumps, or bulges should be investigated because they could indicate structural deterioration.
- A cut or tear that is deeper than 25mm or 10% of the tyre's width, whichever is greater, and deep enough to reach the ply or cord.
- Any section of the ply or cord that is visible.
2. Inflate the tyres to the proper pressure.
That includes following the pressure recommendations provided by both your vehicle's manufacturer and the tyre manufacturer.
Olympus Mobile Tyre Fitting
If you are in the Hertfordshire to London area and are unsure if your vehicle tyres are legal, or want to replace your tyres, contact the mobile tyre fitters at Olympus tyres Potters Bar who will be happy to advise you.
