Tyre tread is designed to create grip and displace water. It comprises of the pattern of grooves along the surface of the tyre.
You can use a tyre tread gauge or 20 pence coin to check your tyre tread is within the legal limit of 1.6mm. Ensure your car is parked in a safe place where you are able to check each tyre. If using a gauge place it between the grooves, taking the reading from the central third of the tread, if it reads over 1.6mm the car is safe to drive.
If using a 20 pence coin perform the same procedure, but use the border around the outside edge of the coin as a guide. If this is not visible the tyre is legal to drive on. If the coin doesn’t go deep enough into the tread the tyre will be illegal. If this is the case, you should get your tyres checked or replaced as soon as possible.
It’s important to test at least 3 points on each tyre when you are checking your tread depth. Also, make sure to check your tread at least once a month or every week to ensure they are always above the legal depth.
Although the legal limit is 1.6mm, tyre efficiency is highly reduced when the tread is below 3mm, especially in wet conditions when stopping distance is increased. It is therefore advised that tyres are replaced before they reach the legal limit.