Most signs your tyre needs replacing show up long before the tyre fails. Some you can see on the drive, while others you’ll feel through the steering. We cover Essex and London, and we’ll tell you straight whether a tyre can be repaired or needs replacing.
Legal tread depth and why it matters
The legal minimum tread for cars, light vans and light trailers is 1.6 mm. As annex 6 of the Highway Code puts it, they must have a tread depth of at least 1.6 mm across the central 3 quarters of the breadth of the tread and around the entire circumference.
The law covers more than depth. Tyres must also be correctly inflated and free from certain cuts and other defects, so a tyre with plenty of tread can still be unroadworthy. GOV.UK sets out the same points in its guide to checking your vehicle is safe to drive.
Tread moves water away from the contact patch, so as it wears the tyre has less grip in the wet and needs more distance to stop.
GOV.UK suggests a quick check: place a 20p coin into the main grooves of the tread. If you can’t see the raised outer rim of the coin (with the words “Twenty pence” engraved), then the tyre has sufficient tread depth. If you can see the rim, have the tyre checked. Try more than one point. Uneven wear matters too, because one worn edge can drop below the legal limit while the rest still looks deep.
Damage you can see and feel
Any bulge, deep cut, tear or exposed cord means the tyre needs replacing. These aren’t cosmetic faults but signs of damage inside the tyre’s structure. Don’t ignore a bulge.
Walk round the car and check both sidewalls. A bulge or blister usually means the internal cords have been damaged, often after hitting the edge of the road or a pothole. Exposed cord or wire means the rubber has worn or torn through. Get it checked.
You’ll sometimes feel a problem before you see it. Vibration through the steering wheel, a pull to one side, or a thumping noise that changes with speed can point to a tyre fault, but balance or alignment issues cause them too, so get the wheel looked at rather than guessing.
| Sign | What it usually means | What to do |
|---|---|---|
| Tread at or near 1.6 mm | Tyre is at or below the legal limit | Arrange a replacement |
| Raised outer rim of a 20p coin can’t be seen | Tyre has sufficient tread depth by the GOV.UK check | Keep checking it regularly |
| Bulge or blister on the sidewall | Internal structure is damaged | Stop using it and replace it |
| Exposed cord or wire | Rubber has worn or torn through | Replace it, don’t drive on it |
| Deep cut or tear | Tyre structure may be compromised | Have it inspected, likely replacement |
| Uneven wear on one edge | Possible alignment or pressure problem | Replace if below limit, then get it checked |
| Vibration or pulling | Tyre damage or a balance issue | Get the wheel inspected |
| Slow, repeated loss of pressure | Possible puncture | Ask whether a repair is possible |
When a puncture is no longer a repair
A small puncture in the main tread can often be repaired, but sidewall or shoulder damage, or a tyre that’s been driven on while flat, usually means replacement.
Where the damage sits matters. The sidewall flexes constantly, so a puncture or cut there can’t be fixed safely, and the shoulder, where the tread meets the sidewall, is treated the same way.
Driving on a flat is the other common reason a repair gets ruled out, because even a short distance can crush the inside of the tyre in ways you can’t see from outside. A blowout means the tyre is finished. Don’t drive on it.
If your puncture might still be fixable, our mobile puncture repair Essex page explains how we can help, and we’ll talk through repair versus replacement when you call or message.
When the answer is a new tyre, our mobile tyre replacement Essex page covers that work. We come to you at the roadside, at a home or driveway, or at work. Drivers near Epping can see our emergency tyre replacement Epping page, which covers places such as Loughton and Theydon Bois.
Key takeaways
The legal limit is 1.6 mm across the central 3 quarters of the breadth of the tread and around the entire circumference. Bulges, exposed cord and deep cuts mean replacement, not repair, and sidewall or shoulder damage can’t be safely repaired. If you’re unsure, ask for a free quote.
When it is not the right choice
This guide isn’t the right choice if your tyre has failed on the road and you’re stranded. Deal with your safety first. Read the checklist later.
The Highway Code advice on breakdowns is clear: get your vehicle to a place of relative safety if you can, switch on your hazard warning lights, and wear fluorescent or light coloured clothing in daylight, and reflective clothing at night or in poor visibility. Never stand between your vehicle and passing traffic. On a motorway, don’t use a warning triangle. If you can’t get out safely, stay in the vehicle with your seat belt on and call 999.
Once you’re safe, call us on 07466 022007 for roadside tyre repair Essex. We’ll check availability when you call and give you a rough arrival time. We work 24 hours, 7 days a week. Tell us where you are and your tyre size.
Common questions
Does the 1.6 mm rule apply to the whole tyre?
It applies across the central 3 quarters of the breadth of the tread and around the entire circumference. The outer edges aren’t part of that measurement, but a tyre with worn edges or exposed cord can still fail on defects. If the centre band is close to the limit, plan a replacement soon.
Can I keep driving on a tyre with a sidewall bulge?
No. A bulge means the internal structure is damaged and the tyre could fail without warning, so it needs replacing, not repairing.
Do all 4 tyres need changing at the same time?
Not always. It depends on how worn the others are, whether they match, and the type of vehicle. Very different tread depths on the same axle can affect handling, so we’ll check them all and give you an honest view on what needs doing.
What should I do if my tyre has already gone flat at the roadside?
Your safety comes first. Get to a safe place if you can, put your hazard lights on and keep away from traffic, then call 07466 022007 or message us on WhatsApp. Try not to drive further on the flat, as that can turn a repairable puncture into a replacement.
Sources
- Highway Code annex 6, legal tread and tyre condition: https://www.gov.uk/guidance/the-highway-code/annex-6-vehicle-maintenance-safety-and-security
- GOV.UK advice on making sure a vehicle is safe to drive: https://www.gov.uk/check-vehicle-safe
- National Highways advice on GOV.UK, including the 20p coin tread check: https://www.gov.uk/government/news/call-to-check-vehicles-before-travelling-as-41500-breakdowns-caused-by-tyre-issues
- Highway Code, what to do after a breakdown: https://www.gov.uk/guidance/the-highway-code/breakdowns-and-incidents-274-to-287