UK Tyre Law

Tread depth

The law states that:

“Cars and light trailers (including caravans) up to 3500kgs gross vehicle weight and/or eight seated passenger vehicles (including the driver), must have a minimum of 1.6mm of tread depth in a continuous band across the central three quarters of the tread width, throughout the entire circumference of the tyre.”

What the law requires

The principal points of the regulations relating to tyre condition are:

  1. Tyres must be suitable (of the correct type and size) for the use to which the vehicle is being put, and must be inflated to the vehicle or tyre manufacturers’ recommended pressures.
  2. Tyres of different types must not be fitted to opposite wheels of the vehicle (for example, radial-ply tyres must not be fitted to a wheel on the same axle as wheels already fitted with cross-ply tyres and vice versa, and a two-axle vehicle with single rear wheels must not have radial ply tyres on the front axle if cross ply tyres are fitted to the rear axle).
  3. No tyre must have a break in its fabric or a cut deep enough to reach the body cords. No cut must be more than 25mm or 10% of the tyre’s section width in length, whichever is the greater.
  4. There must be no lump, bulge or tear caused by separation or partial fracture of its structure, neither must any portion of the ply or cord structure be exposed.

The penalties for offences related to the use of faulty tyres on vehicles can be quite severe.

In the case of any vehicle, except goods vehicles and vehicles adapted to carry more than eight passengers, for every offence there is a fine at level 4 of the standard scale with discretionary disqualification and compulsory driving licence endorsement with 3 penalty points.

Level 4 is currently £2500 and each faulty tyre is considered as a separate offence.

If you are planning to take your vehicle abroad, most countries require a minimum tread depth of 1.6mm, like the UK. We recommend that you should consider replacing your tyres prior to any trip if the tread depth is down to 3mm. Always bear in mind the amount of mileage you may cover.

Remember, at 3mm of tread depth you only have 1.4mm of useable tread remaining!!!

Tyres@Home recommend that you regularly inspect your tyres for faults. See Checking your tyres for more information.

ECE Markings

For a tyre to be legally used in the UK, it must carry an ‘E’ or ‘e’ letter which shows that it is approved to European Standards for tyre loads and speeds.

Each tyre make and type will have a unique 5 or 6 digit number following the ‘E’ letter which is a reproduction of the certificate of approval number. The ‘E’ certifies that the tyre complies with the dimensional, performance and marking requirements of ECE Regulations (R30 in the case of passenger and R54 in the case of Commercial). The ‘E’ certifies that the tyre complies with the dimensional, performance and marking requirements of DIRECTIVE 92/23/EEC and relates to tyres without specific speed rating for example ZR tyres (Passenger only).

The number associated with the letter ‘E’ in the circle or ‘e’ in the rectangle is the code number of the government which granted the approval.

It should be noted that if there is no certificate number then the E or e mark is not valid.

At present ECE marks are not yet a legal requirement unless the regulations have been ratified by the parliament of the individual.

Tyres will now have additional e-marks for meeting the new European noise regulations.

Construction & Use Regulations

The Construction & Use Regulations No.27 regulates the use of and condition of tyres in UK operation. Whilst there are many aspects covered within C & U Regulations, the main points in lay terms are shown below:

1. Suitability of application

A section of C & U, which is open to interpretation, but essentially it means the tyre must be suitable for the use it is being subjected to.

2. Inflation Pressure

Essentially, the rule is the inflation pressure must be suitable for the use applied to the tyre. Tyre pressure recommendations are quoted in the vehicle handbook and usually displayed on a placard somewhere on the vehicle itself.

3. Minimum tread depth

C & U stipulates the depth of remaining tread pattern at which a tyre becomes illegal to use. This is described in greater detail later (Note: the minimum tread depth is different for cars than for trucks)

4. Cuts, bulges tears etc

This section essentially relates to tyre damage & exposed cords. It defines limits of damage, which must be adhered to. Common sense should prevail, if a tyre is damaged it should be repaired or scrapped if irreparable.

5. Re-grooving

Car and van tyres do not meet all stipulations and hence may not be re-grooved.

6. Mixing of tyre constructions

Because tyres with different constructions (Radial, Cross ply, Bias belted) have different performance characteristics there are strict rules regarding mixing them on a vehicle. Please call our support team for further advice.

Construction & Use Regulations Condition & Maintenance of Tyres (Reg.No27)

Summary of main points of paragraphs (1) & (4) which relates to cars, light and heavy commercial vehicles and motorcycles.

A motor vehicle or trailer fitted with pneumatic tyres shall not be used on a road if:

[A] The tyre is unsuitable for the purpose for which the vehicle is being used or is incompatible with other tyres on the vehicle.

[B] The tyre is not so inflated to make it fit for the use the vehicle is being used or is incompatible with other tyres on the vehicle

[C] The tyre has a cut in excess of 25mm or 10% of the tyre section width, whichever is the greater, measured in any direction on the outside of the tyre and deep enough to reach the ply or cord

[D] The tyre has a lump, bulge or tear caused by a separation or partial failure of its structure.

[E] The tyre has any of the ply or cord exposed.

[F] & [G] Relate to minimum tread pattern depths

[H] The tyre is not maintained in such a condition as to be fit for the use to which the vehicle or trailer is being put or has a defect which might in any way cause damage to the road surface or damage to persons on or in the vehicle or to other road users.