Winter Tyres “M+S”

In countries where severe winter weather conditions are more or less guaranteed, it is quite normal for drivers to switch to winter tyres for the duration of the cold season.
Harsh winters in Britain, however, are still fairly unusual and far fewer drivers change their tyres to suit the weather – although the take-up is increasing rapidly and the Institute of Advanced Motorists has now published some guidance on the pros and cons of the various options – winter tyres, all-season tyres, snow chains and snow socks.
According to the IAM, there are two main differences between winter and normal tyres. Winter tyres have a different tread pattern of wider grooves and narrow slits at the edges of the tread area, which means better grip on snow and ice.
The second difference is the material the tyre is made of. The rubber used on standard tyres gets stiffer as the temperature drops, and grip starts to reduce below seven degrees Celsius. Winter tyres use a different material which stays soft and grippy to well below zero. Tyres made with this rubber carry either a snowflake or mountain symbol on the sidewall.
Winter tyres do have drawbacks in terms of storage and cost, however. Most European drivers who make the switch to winter rubber have two sets of wheels and tyres, so they can change over easily. Changing to winter tyres permanently is unadvisable as they have less grip when the weather warms up, will wear out more quickly and will cause the vehicle to use more fuel.
A compromise solution is all-season tyres. As a result of the rubber compound used and tread, they can be used all year round as the name implies – but like any compromise they will not be as good as standard tyres in summer or winter tyres in snow and ice. Because they use the same rubber compound as winter tyres, they should have the snowflake or mountain symbol. But they may also have a sun symbol or be marked “M+S” (Mud and Snow).
The alternative to changing tyres is to carry snow chains or snow socks for when the snow gets deep. Either can be used with standard tyres. Snow chains are more effective than socks, but do have a few drawbacks. They increase the width of the tyre and may affect the suspension, ABS brakes, or wheel arch on a turn – your owner’s handbook or a dealer will be able to tell you if chains can be fitted.
They can also be a chore to fit, and anyone buying them should practice fitting them before the bad weather sets in. Driving with snow chains on a clear road surface could cause damage, and be an offence, so you mustn’t fit them until there is a blanket of snow and you must stop as soon as the snow has gone and remove them. Expect to pay around £50 for a set of economy chains, and up to a couple of hundred pounds on a heavy duty set suitable for regular use.
Snow socks, meanwhile, are slightly cheaper to buy – typically about £40 upwards – are much easier to fit, and will give sufficient grip for most snowy conditions in the UK. Made of a strong fabric which grips snow, they stretch to fit over the tyre.
They do not damage roads, although they will wear out quickly if driven for any distance on tarmac and should be removed as soon as safe to do so. Both chains and socks should be washed as soon as is practical after use to get rid of dirt and salt that will otherwise corrode them.
“With extremes of cold weather being unusual here, and the UK government showing no signs of making winter tyres compulsory, there is no obligation to invest in them,” the IAM’s chief examiner Peter Rodger said. “Nevertheless, it could be a sensible option for some – those living and working at high altitude or in remote areas for example. For the rest of us, justifying the cost depends on individual circumstances such as annual mileage and whether you have the option not to drive in extreme weather conditions.”

winter tyres