Your tyre tread depth directly affects how well your car grips the road, handles corners, and stops in wet conditions. In this guide, we explain the difference between legal and recommended tread depths — and why replacing tyres early keeps you safer and saves you money long term.
Your tyre tread depth is always changing as you continue to use your vehicle. The design of tyres and the use of rubber in constructing these tyres, means that regular use causes the tread to gradually wear away – until it reaches the cut-off between being safe and legal, and no longer being suitable for use on the road.
The tread depth at which tyres move from being legal to illegal is well-documented: 1.6mm across virtually all vehicle types.
Let’s take a closer look at what happens as tyre tread starts to become worn, and why higher tread is better.
What Does Tyre Tread Do?
Tyre tread is the outer layer on a tyre, which makes contact with the road and is responsible for ensuring good grip and traction, as well as a comfortable driving experience.
It is comprised of rubber tread blocks which sit around the external surface and do everything from navigating sharp corners to dispelling surface water.
What Happens As Tyre Tread Wears Down?
When you first fit new tyres to a vehicle, they have a tread depth of around 8mm. This is standard for new tyres, which then require a period of wearing in to ensure that the surfaces are scratched up enough to facilitate good grip and friction.
As you drive, your tyre tread becomes worn. This impacts several things, including the friction between your tyres and the road, the comfort of the drive, and stopping distances when braking.
One of the challenges that drivers face when managing tyre maintenance, is the potential that the tyre tread will not wear down evenly. If tread wear is uneven, it hints at an imbalance in the alignment of the tyre and can leave the tyres more difficult to control.
The minimum tread depth that you can legally drive with is 1.6mm. So, what happens as you transition from 8mm to 1.6mm?
When is Tyre Tread No Longer Safe?
Any tread that reads above the 1.6mm legal limit is considered legal and safe.
However, most drivers will look to replace tyres once the tread wear hits 2mm – as beyond this, you are bordering on unsafe.
