How and when should I check my car's tyres?

Created by Jonathan Fry, Modified on Fri, 18 Apr at 10:53 PM by Jonathan Fry

Key Points

The Highway Code requires tyres to be correctly inflated and have at least 1.6 mm tread depth for cars, light vans, and trailers, free from defects.
It seems likely that checking tyre pressure weekly and before long journeys, when cold, is advised for safety.
Research suggests drivers should inspect tyres for cuts, bulges, and uneven wear to ensure roadworthiness.

Tyre Checking Advice from the Highway Code

The Highway Code, the official guide for UK road users, provides clear advice on tyre maintenance. It states that tyres must be correctly inflated according to the vehicle manufacturer’s specification for the load being carried, with checks recommended weekly and before long journeys, especially when tyres are cold to ensure accuracy. For cars, light vans, and light trailers, the tread depth must be at least 1.6 mm across the central three-quarters of the tread and around the entire circumference. Additionally, tyres should be free from certain cuts and other defects to ensure safety.

Guidance for Drivers on Checking Tyres

To help drivers maintain their tyres, here are practical steps:

Tyre Pressure: Find the correct pressure in your vehicle’s handbook or on a sticker inside the driver’s door. Use a tyre pressure gauge to check when tyres are cold, and adjust if necessary. For a video guide, see this tutorial.
Tread Depth: Use a tread depth gauge or the 20p coin test—if the outer band is visible when inserted, the tread is too low. Ensure it meets the 1.6 mm legal minimum across the required area. Watch this video for expert advice.
General Condition: Inspect tyres for cuts, bulges, or embedded objects, and check for uneven wear, which may indicate alignment or suspension issues.

These steps help ensure tyres are safe and legal, reducing the risk of fines and improving road safety.

Comprehensive Survey Note on Tyre Checking Advice and Guidance

This section provides a detailed exploration of the advice given by the Highway Code regarding tyre checks and offers comprehensive guidance for drivers, including practical steps and supporting resources. It builds on the direct answer, incorporating all relevant details from the research process to ensure a thorough understanding for UK drivers.

Background and Context

The Highway Code, published by the UK government, serves as the official guide for road users, outlining rules and advice to ensure safety on the roads. Given its legal and practical importance, it includes specific guidance on vehicle maintenance, particularly tyre checks, which are critical for road safety. Tyres are the only point of contact between a vehicle and the road, making their condition vital for handling, braking, and fuel efficiency. The research focused on identifying the Highway Code’s recommendations and providing actionable guidance, including links to tutorial videos, to assist drivers in maintaining their tyres effectively.

Highway Code Advice on Tyre Checks

The Highway Code, as detailed in Annex 6 on vehicle maintenance, safety, and security, provides explicit advice on tyre checks. It mandates that tyres must be correctly inflated to the vehicle manufacturer’s specification for the load being carried, emphasizing the importance of regular checks. Drivers are advised to check tyre pressure weekly, before long journeys, and when tyres are cold, as warm or hot tyres can give misleading readings. Under-inflated or over-inflated tyres can adversely affect braking and steering, posing significant safety risks.

For tread depth, the Highway Code specifies that cars, light vans, and light trailers must have at least 1.6 mm of tread depth across the central three-quarters of the tread breadth and around the entire circumference. Motorcycles, large vehicles, and passenger-carrying vehicles have a minimum of 1 mm across three-quarters of the tread breadth in a continuous band, while mopeds require visible tread. Additionally, tyres must be free from certain cuts and other defects, with excessive or uneven wear potentially indicating faults in braking, suspension systems, or wheel alignment, which should be corrected promptly.

The Highway Code also addresses tyre age, noting that tyres over 10 years old must not be used on the front axles of goods vehicles over 3.5 tonnes maximum gross weight or passenger vehicles with more than 8 passenger seats. They are also prohibited on the rear axles of passenger vehicles with 9 to 16 passenger seats, unless equipped with twin wheels, with the date of manufacture marking required to be legible. Exemptions apply to vehicles excluded from tyre roadworthiness regulations and those of historical interest not used commercially, as per CUR reg 27.

In case of a tyre burst or flat tyre, the Highway Code advises gripping the steering wheel firmly if a tyre bursts, allowing the vehicle to roll to a stop at the side of the road. For a flat tyre, drivers should stop safely and only change the tyre if it can be done without risking themselves or others; otherwise, they should call a breakdown service. It also warns that some vehicle defects, including tyre issues, can attract penalty points, and if the vehicle pulls to one side when braking, it may indicate a brake fault or incorrectly inflated tyres, requiring immediate consultation with a garage.

Detailed Guidance for Drivers on Checking Tyres

To assist drivers in implementing the Highway Code’s advice, the following guidance covers practical steps for checking tyre pressure, tread depth, and general condition, supported by tutorial videos for clarity.

Tyre Pressure

Tyre pressure is a critical aspect of tyre maintenance, affecting safety, fuel efficiency, and tyre lifespan. The correct pressure is typically listed in the vehicle’s handbook, on a sticker inside the driver’s door, near the petrol cap, or online for the specific make and model. Drivers should check the pressure when tyres are cold, as heat from driving can increase pressure and give inaccurate readings. The Highway Code recommends weekly checks and before long journeys, with research suggesting that under-inflated tyres can increase braking distances, make steering harder, reduce fuel efficiency, and shorten tyre life, while over-inflated tyres can cause uneven wear and reduced grip.

To check tyre pressure, drivers can use a tyre pressure gauge, available at most fuel and service station forecourts or for personal purchase. The process involves removing the valve cap, inserting the gauge into the valve, and pushing until the hissing noise stops, then comparing the reading to the recommended PSI or BAR (metric) value. If the pressure is low, drivers can inflate the tyres using an air machine at a forecourt, ensuring not to exceed the recommended level. If too high, releasing air by briefly removing the valve cap can adjust it. For a detailed video tutorial, drivers can refer to How To Check Your Tyre Pressure, which provides a quick guide on the process.

Tread Depth

Tread depth is another crucial factor, with the legal minimum in the UK being 1.6 mm for cars, as per the Highway Code. However, safety experts, such as the Royal Society for the Prevention of Accidents (RoSPA), recommend replacing tyres well before reaching this limit, ideally at 3 mm, due to increased stopping distances below this threshold. Driving with tyres below the legal limit can result in fines of up to £2,500 per tyre, three penalty points per tyre, and potential insurance claim invalidation in accidents, with risks of up to £10,000 fines and 12 penalty points for four illegal tyres.

To check tread depth, drivers can use a tread depth gauge for precision, available at automotive stores, or employ the 20p coin test mentioned in resources like NFU Mutual’s guide. Inserting a 20p coin into the tread, if the outer band is visible, indicates the tread is below the legal limit. The Highway Code requires this check across the central three-quarters of the tread and around the entire circumference. For a video demonstration, How to check your car's tyre tread – expert advice from the RAC offers expert guidance, showing how to identify tread wear indicators and assess legality.

General Condition

Beyond pressure and tread, checking the general condition of tyres is essential for safety. Drivers should inspect each tyre for visible cuts, bulges, or other defects, which can compromise integrity and lead to failures. Embedded objects, such as nails or glass, should be noted and addressed, potentially requiring professional removal. Uneven wear, where one part of the tyre wears faster than others, may indicate issues with wheel alignment, suspension, or braking systems, and should be corrected as soon as possible to prevent further damage. The Highway Code highlights that such defects can attract penalty points, emphasizing the need for regular inspections.

Drivers can perform these checks visually, ensuring the vehicle is on a level surface and, if possible, rotating the wheels for a full view. For additional resources, websites like Which? Trusted Traders and Protyre offer advice on home checks, noting the importance during cold weather months when tyre performance can be affected by icy roads.

Supporting Resources and Tutorial Videos

To enhance understanding and practical application, several tutorial videos were identified, focusing on both tread depth and tyre pressure checks. The RAC video (How to check your car's tyre tread – expert advice from the RAC) provides expert advice on checking tread, while Motoring Assist’s video (How To Check Your Tyre Pressure) offers a quick guide on pressure checks. These resources, published by reputable organizations, ensure drivers have access to reliable, visual instructions, complementing the textual guidance provided.

Summary Table of Tyre Check Requirements

To organize the key points, the following table summarizes the Highway Code requirements and recommended actions:

Aspect	Highway Code Requirement	Recommended Action
Tyre Inflation	Correctly inflated to manufacturer’s spec for load carried	Check weekly, before journeys, when cold; use gauge, adjust at forecourt if needed
Tread Depth	At least 1.6 mm across central three-quarters, full circumference	Use gauge or 20p coin test; replace ideally at 3 mm for safety
Tyre Condition	Free from cuts, defects; no excessive/uneven wear	Inspect visually for cuts, bulges, objects; address uneven wear promptly
Tyre Age	Over 10 years old, restrictions for certain vehicles	Check manufacture date; ensure legible marking, follow exemptions if applicable
Burst/Flat Tyre	Safe stopping procedure required	Grip wheel if burst, roll to stop; for flat, stop safely, change only if safe or call breakdown

This table encapsulates the essential advice, aiding drivers in maintaining compliance and safety.

Conclusion

The Highway Code provides clear, legally binding advice on tyre checks, emphasizing inflation, tread depth, and condition to ensure road safety. Drivers can follow practical steps for checking pressure, tread, and general condition, supported by tutorial videos for hands-on learning. Regular maintenance, as outlined, not only complies with the law but also enhances safety, reduces fuel costs, and prevents costly fines, making it a critical aspect of responsible driving in the UK.

Key Citations