What are run-flat tyres and can any fitter work on them? +
Run-flat tyres have reinforced sidewalls that support the weight of the car even with no air pressure, allowing you to drive up to 50 miles at 30mph after a puncture. They require specialist fitting equipment and a TPMS reset after replacement. Not all garages can work on run-flat tyres, but most professional mobile fitters and tyre centres are fully equipped. Run-flat tyres are typically 20–40% more expensive than standard equivalents.
What is the legal minimum tyre tread depth in the UK? +
The legal minimum tread depth in the UK is 1.6mm across the central three-quarters of the tyre, around its entire circumference. However, most motoring organisations recommend replacing tyres at 3mm, as braking performance drops significantly below this level. Driving on tyres below 1.6mm carries a fine of up to £2,500 and 3 penalty points per illegal tyre — so four bald tyres could mean a £10,000 fine and 12 points.
Can a tyre blowout be repaired or does it need replacing? +
A tyre that has suffered a blowout almost always needs replacing. The internal structure of the tyre is usually destroyed by the sudden loss of pressure and the impact damage that follows. Even if the tyre appears intact, the sidewall and carcass will have been compromised. A tyre fitter can inspect it, but in the vast majority of cases a new tyre is the only safe option.
Are part-worn tyres safe to buy? +
Part-worn tyres carry significant risks. While they are legal to sell in the UK, studies have found that a large proportion fail to meet legal standards — many have been previously repaired improperly, have internal damage not visible from the outside, or are close to the legal tread limit. The small saving is rarely worth the risk. New budget tyres from reputable brands often cost only £15–£25 more and come with a full warranty.
How do I read my tyre size? +
Your tyre size is printed on the sidewall in a format like 205/55R16 91V. The first number (205) is the width in millimetres, the second (55) is the aspect ratio as a percentage of the width, R means radial construction, and 16 is the wheel diameter in inches. The number after (91) is the load index and the letter (V) is the speed rating. Your vehicle handbook and the sticker inside the driver's door frame show the correct size for your car.
How old can tyres be before they need replacing? +
Even if the tread looks fine, tyres degrade over time as the rubber compound hardens and loses grip. Most manufacturers recommend replacing tyres after 5 years of use, and no tyre should remain in service for more than 10 years from the date of manufacture. You can check the age using the DOT code on the sidewall — the last four digits show the week and year of manufacture (e.g. 2319 means week 23 of 2019).