Minimum legal tread depths

[thexav]

What is the minimum legal tread depth in the UK, and if you in another country it will be interesting to compare to see what you have to work with.

Also is this just for 1 third of the tyre width? What about bald patches from heavy braking? Do these render a tyre illegal?

 

[TCJBOLDIE]

Basically the minimum tread depth is governed by the Tread Wear Indicators(TWI's) that are a small raised bump in the grooves of the tread and there are a number of triangular indicator markings around the sidewalls to show where the TWI's are to be found.
IMMSMC the minimum depth of tread anywhere is 1.5mm or the old fashioned match head thickness.

What many drivers fail to realize is wile a tyre with minimal tread will grip well in the dry they are lethal in the wet due to the lack of tread depth being unable to pump out the water to allow the tyre to grip the road .

 

[old-git]

Is this MOT day?

MOT testers manual

4.1Tyres (Tread pattern, bredth and depth)

The grooves of the tread pattern must be at least 1.6mm depth throughout a continuous band comprising the central three-quarters of the breadth of tread, and round the entire outer circumference of the tyre.

Note: Each side of the central band of the tyre can be devoid of tread (ie. ‘bald’) and still meet the pass.