Ultimate Guide to Tyre Tread Depth and Safety Standards
As a driver in the UK, you have to make sure that your vehicle is fitted with roadworthy tyres. Being roadworthy means to comply with all legal and safety requirements. If your tyres are found to be below the legal tyre tread depth limit for UK roads, you run the risk of being fined, receiving penalty points on your driving licence and potentially being disqualified from driving. Defective tyres can put yourself, your passengers and other road users in danger.
What is Tread Depth?
Tread depth refers to the thickness of the outer part of a tyre that contacts the road. It's essential for maintaining grip, especially when driving in wet conditions.
It's important to know that the minimum legal requirement for tyre tread depth in the UK is 1.6 millimetres. This should be across the central three-quarters of your tyre's tread and all around each tyre.Over time, this tread wears down and needs to be monitored to ensure safe driving. For safety reasons, it is recommended that you replace your car tyres before the legal limit is reached.
Many vehicle producers recommend replacing at 3 millimetres. Why? Below this depth, stopping distances start to dramatically increase. At 1.6 millimetres in wet weather, it takes an extra two car lengths (8 metres) to stop at 50 mph, compared to if your tread was 3 millimetres!
For more tips on Driving in Heavy Rains and Floods, check out our blog!
How To Measure Tread Depth
- Tread Depth Gauge: This is the most accurate way to measure. You can buy a tread depth gauge, which is not expensive. To use it, you put the gauge's pin into the groove of the tyre and press the base of the gauge against the tyre to see the depth.
- 20p Coin Test: You can use a 20p coin for a quick check. Put the coin into the tyre's grooves in several spots. If the outer edge of the coin is hidden, your tread is still fine. If you can see the edge, your tyres might be too worn and need a professional check.
- Wear Indicators: Many tyres have built-in indicators. These are small raised lines in the grooves. When the tyre tread is level with these lines, it's time to get new tyres.
What Types of Tyre Tread Depth Are There?
Multi-Directional/Symmetrical Treads
- Ideal for Budget-Conscious Drivers: Multi-directional or symmetrical tread patterns are a great choice for drivers who have a budget.
- Versatility and Cost-Effectiveness: The symmetrical design means that the tread pattern on the inside of the tyre matches the pattern on the outside. This feature allows you to place them anywhere on your vehicle, making them cost-effective because you don't need to order four different tyres for your car.
- Suitable for Various Road Conditions: Multi-directional treads perform well in a variety of road conditions, making them a practical choice for the unpredictable UK weather. They provide decent traction on wet roads and maintain stability during dry spells.
Asymmetric Treads
- Dry and Wet Weather Performance: These tyres feature a different tread pattern on the inside and outside, allowing them to excel in both dry and wet conditions. They are a versatile choice for the unpredictable UK climate.
- Consideration for Mounting: Keep in mind that asymmetric tyres need to be mounted in a specific direction on your car's wheels for optimal performance. While this may add a bit of complexity during installation, it ensures that you get the most out of these tyres.
Directional Treads
- Enhanced Grip in Rainy Weather: Directional tread patterns are the top choice for drivers who prioritise superior grip, especially in rainy conditions.
- Effective Water Dispersion: These tyres have an arrow-like design that efficiently channels water through the tread and displaces it, providing excellent grip even in wet conditions. It is also useful against aquaplaning in heavy rain.
- Consideration for Mounting: Like asymmetric tyres, directional tyres must be mounted with all treads facing the same direction. This means they will be oriented differently on the left and right sides of your car.
Regular tyre maintenance is essential for meeting UK legal standards and ensuring your safety. Whether it's rainy, dry, or wet conditions, the right tyre can make all the difference. Don't forget to get your tyres professionally checked for an extra layer of safety, especially before long journeys or during seasonal changes.