Unsafe Tyres: Why Driving on Them Is Illegal

Your tyres are the only contact point between your car and the road — so when they’re unsafe, everything else is too. In this guide, we explain what counts as an unsafe tyre, why driving on them is illegal, and the simple checks that can help you stay safe and avoid fines. Learn how to protect yourself, your car, and others on the road.

The tyres on a car are the only part of that car that makes contact with the road. They are responsible for controlling the car’s direction, for maintaining good grip and traction with the road surface and keeping the car moving smoothly.

They are, in short, integral to the car’s safety. 

So, when the tyres are deemed unsafe, it’s fair to conclude that the entire vehicle becomes unsafe – both for those in the car, and those in other cars that are sharing the same stretch of road.

In this article, we’re looking at what constitutes an unsafe tyre, why driving on unsafe tyres is illegal, and the checks you need to perform to keep tyres in good working order.

What is an Unsafe Tyre?

An unsafe tyre is one which shows signs of damage or excessive wear, impacting the tyres ability to exert full control over the vehicle’s direction, speed, braking distance, and overall controllability on the road.

Some of the hallmarks of an unsafe tyre, particularly one which would be classed as illegal, include:

• Tread depth that measures below 1.6mm 
• Cracks or bulges in the structure of the tyre and its sidewall 

You can also class an unsafe tyre as one which is unsuited to the terrain that you are driving on, the environmental conditions, or the vehicle itself.

Why Are Unsafe Tyres Classed as Illegal?

All things considered unsafe tyres impact the ability of the driver to control the vehicle properly and leave the vehicle more susceptible to being involved in an accident. This could be through a loss of control on icy roads, through the increased risk of a puncture, or through being unable to brake efficiently and stop the car quickly.

If you are caught driving on tyres which are legally classified as unsafe, you will be fined and your vehicle removed from the road until the tyres have been replaced. This is primarily for safety. 

Regular Checks for Your Tyres

The main checks you need to perform on your own vehicle’s tyres are pressure checks and tyre tread checks. You also need to regularly inspect the tyre sidewall to ensure that there are not bulges or cracks visible that could be impacting the structural integrity and stability of the tyre.

• If tyres keep losing their pressure and are regularly found to be under the recommended pressure, it could be that you have a slow puncture or damage to the tyre. In this case, the tyre will need to be repaired professionally or replaced – depending on the severity of the damage. 
• If the tread depth on your tyres is measuring close to 1.6mm, they need to be replaced immediately. 1.6mm is the minimum legal limit, with any tyres measuring at 3mm or under recommended for replacement as soon as possible.
• If tyres exhibit signs of damage on the sidewall, then it’s important that you replace the tyres immediately. While minor damage to the outer edge of the tyre and its tread can sometimes be repaired, any damage to the sidewall impacts the internal structure of the rubber compound and is unsuitable for repair. 
• If the tyre does not match the other tyres in terms of its seasonal compatibility or size. To ensure balance across the vehicle and a consistent response to steering, braking, and road conditions, the tyres all need to be the same size and of the same seasonal design. 

At Tyres.co.uk, we offer a range of tyres for all occasions – with replacement tyres that you can shop whenever you find that one or more of your existing tyres fall into the ‘unsafe’ category. Shop online now or get in touch for tailored advice and information.