Tyre tread depth essentials, and how to easily check yours

We’re all used to being inundated with statistics, many often trivial and not worthy of attention, but some are seriously worth knowing about. This is especially true if you’re a UK motorist when it comes to vehicle-related accidents. The most complete annual figures – from 2016 – show that there were over 37 million vehicles licensed for use on the UK roads. These amassed 1.87 billion car miles were driven, with just under 180,000 casualties on the road. Unfortunately, 1,792 were fatalities – at record levels since 2011.

It can be difficult to comprehend such large figures, so consider this small number: 1.6mm – the minimum tread depth your tyres have to have to be road legal in the UK. 1.6mm doesn’t sound a lot, but it’s the difference between having tyre grip, and becoming one those road casualties.

Sound overly dramatic? Consider this; the area of a tyre that is in contact with the road at any given moment is approximately the size of a smartphone. That’s it! And with this very limited contact, your tyres are responsible for removing enough water – quickly enough – to ensure grip is maintained with the road.

To achieve this, your tyres require sufficient tread depth to successfully do the task. Unfortunately, there are many drivers that don’t realise this, and, as a result, allow their tyres to wear down – to the point where they no longer have adequate tread depth to maintain grip with the road. That’s alarming for all road users.

Stopping distances – and the threat of aquaplaning

While is 1.6mm is the UK road legal tyre tread depth mimimum, many road safety organisations, and tyre experts, like Asda Tyres, TyreSafe, and leading premium tyre manufacturer, Continental, recommend that your tyres have a minimum tread depth of 3mm. That’s almost double the UK legal minimum.

Why 3mm instead of 1.6mm?

Numerous independent stopping distance tests have conclusively demonstrated that in wet weather conditions – something we get a lot of in the UK, right? – the difference in breaking distance for 1.6mm vs 3mm tread depths is almost double the length to come to a full stop. If you’re trying to avoid an impact on a fast moving motorway with 1.6mm of tread, that’s very worrying.

The graphic, above, demonstrates the difference in stopping distances for vehicles fitted with summer tyres on a wet road. Even at relatively modest speeds (21 mph residual speed for the 3mm tread, and 27 mph residual speed for the 1.6mm tread) the difference is alarming.

In a built-up, town or city environment – such as a side road where school children are distracted while crossing the road, for instance – the consequences of taking longer to come to a safe, full stop are potentially fatal. And as for travelling at high speed on a motorway… it doesn’t bear thinking about, does it?

And then there’s the threat of aquaplaning – when tyres completely lose contact with the road, and travel on top of the water. As a result, in these moments, acceleration, braking and steering are impossible, leaving drivers with no control. Fortunately – usually – drivers get control back, but this is not always the case, and can lead to collisions.

A tyre’s tread wear will differ from driver to driver, but…

When a high-quality, premium tyre leaves the factory – such as the award winning ContiPremiumContact™ 5 – this specific tyre features a full 8mm of tread. This allows the tyre to remove large amounts of water quickly and efficiently from the road, delivering essential grip, handling and driver safety. But not all tyres are the same.

A tyre’s compound, in combination with how a car is driven, determines tyre tread depth wear. Many miles a year at 70 mph on motorways will see tyres deteriorate faster than, for instance, doing the school run, or popping into town occasionally for the errands. However, in an exact like for like usage comparison, the superior compounds used for premium tyres will wear down slower than for cheaper, budget tyres.

Ultimately, however, at the end of the day, no matter how you drive all tyres will eventually wear down. The deterioration increases as your tread diminishes. For this reason, it’s essential that you take the time to regularly check your tyre tread depth.

So how do you go about checking your tread depth?

While tyre tread depth gauges are easy to come by, a handy alternative is the “20p Test”. It’s a very useful way of checking your tread, without the need for a gauge. To do so, all you have to do is simply place a 20p coin into the lateral tread grooves that run along the length of your tyres (in the centre). Do this at multiple points for each tyre.

If the coin’s outer band is completely obscured, you can be confident that your tread is above the UK road legal minimum. But if you can still see the top of the band, there’s a very strong possibility that your tyres may be illegal. In this circumstance, you should seek immediate expert advice from your local tyre professionals, and if necessary get new ones fitted.

If you don’t, and you’re stopped by the police with illegal tyres on your vehicle, you risk incurring a fine of £2,500, and three penalty points for EACH illegal tyre. Ouch!

If you’re unsure about tyre tread depths, speak to Asda Tyres

Simply put, your tyre tread depths are vital, and it’s essential that you manage them correctly. If you’re unsure about yours, speak to the Asda Tyres professionals for impartial, expert tyre advice and fitting solutions. We’re here to help ensure your driver safety. Click here to live chat to one of our experts, or find your nearest fitting station.

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