Q405: What is the law relating to tyres?
If you are in any doubt as to whether your tyres are road worthy, take your vehicle along to a reputable garage that will be able to advise you.
The law relating to tyres is as follows -
tyres must be suitable for the purpose of their use;
be inflated as to be fit for the purpose for use to which vehicle is being put (your manual will have the recommended inflation for your vehicle);
have no portion of the ply or cord exposed;
have no lump, bulge or tear caused by separation or partial failure of its structure;
have the base of any groove, which showed the original tread pattern clearly visible (this refers to vehicles requiring only 1mm depth of tread, (vehicles with a maximum authorised mass exceeding 3500kgs; trailers exceeding a MAM of 3500kgs and motorcycles);
have no cut in excess of 25 mm or 10 percent of the section width of the tyre, whichever is the greater, measured in any direction on the outside of the tyre and deep enough to reach the ply or cord;
the grooves of the tread pattern of the tyre have a depth of at least 1.6mm throughout a continuous band comprising the centre three-quarters of the breadth of the tyre and round the entire outer circumference of the tyre. For the 1mm depth requirement it does have to be around the entire circumference for three-quarters of the breadth but not necessarily the centre three-quarters
Tyre tread depth requirements
Passenger vehicles not exceeding 8 passenger seats and goods vehicles/light trailers mgw not exceeding 3500 kg require 1.6 mm of tread in the centre three quarters of the breadth of the tread around the entire outer circumference of the tyre.
Most larger vehicles and motorcycles need at least 1 mm throughout a continuous band across at least three quarters of the breadth of the tread around the entire circumference. In the area where the tread may be less than 1.0 mm, the original tread pattern must be visible.
For mopeds/motorcycles not exceeding 50cc there is no depth requirement other than the original tread pattern must be visible.