Switching to winter tyres: the 4×4×4 rule
When exactly should you change to winter tyres so as not to do it unnecessarily early or too late? Drivers remember the date by the 4×4×4 rule, and it is also good to know the legal obligation associated with changing tyres.
Rule 4×4×4: what it means
The rule is a simple aid to remember the three conditions that together signal it is time for winter tyres.
4 millimetres of tread depth
Winter tyres require a deeper tread than summer tyres because they must channel slush and maintain grip on ice. The recommended minimum is 4 mm, significantly more than the legal minimum of 1.6 mm.
4 degrees Celsius
As soon as the average daily temperature permanently drops below 4 °C, the rubber of summer tyres hardens and loses grip, even on dry and clean road surfaces, i.e. Before the first snow falls.
Fourth month: November
Approximate calendar deadlines for Prague and the rest of the Czech Republic. By November, temperatures and weather conditions usually meet the first two criteria of the rule, so it is high time to have your tyres changed.
Legal obligation for winter tyres
According to Act No. 361/2000 Coll. On Road Traffic, drivers are required to have winter tyres fitted to their vehicles between 1 November and 31 March if winter conditions, meaning a continuous layer of snow, ice or frost, are present on the road surface.
Warning: The law does not automatically require winter tyres for the entire period from 1. 11.-31. 3., but only when actual winter conditions are present on the road surface. In practice, however, it is much safer to rely on the temperature rule than to wait for the first snowfall.
Minimum tread depth for winter tyres
It is worth inspecting last season's winter set before switching tyres, if the tread depth has fallen below 4 mm, the tyre may still be above the legal minimum, but its winter performance is already noticeably worse.
How to tell when it is truly time to change your tyres
It is best to monitor the forecast for the next two weeks, not just the current day: an isolated warm day in November means nothing if temperatures are falling long-term. It is advisable to book your tyre change appointment in advance, as during the peak season services are overwhelmed and lead times extend.
And don't forget to check the tread depth on your own winter set: the 4×4×4 rule applies every year again, not just when buying new tyres.
What You Risk by Using Summer Tyres in Winter
Harder summer tyre rubber at low temperatures grips the road surface less well, even on dry surfaces, let alone wet or icy ones. Braking distance increases, the vehicle holds its line less effectively in corners and is more prone to slipping when accelerating uphill. The difference becomes noticeable already at temperatures around zero, i.e. Before the first snow falls.
Stress-free tyre change with car collection
Instead of monitoring available slots at the physical workshop, simply book your tyre change in advance for a specific date. We collect the vehicle where it is parked, whether at home or work, and return it after the service. This also eliminates the need to find storage for your seasonal set if you opt for our storage solution directly.
When changing tyres, it is also a good opportunity to check tyre pressure, as the temperature drops, the pressure in the rubber naturally decreases, and under-inflated tyres increase fuel consumption and wear. The mechanic will check and adjust the pressure directly during the replacement.
Winter and summer tyres are not swapped solely according to the season
Apart from the actual tyre change, it is worth knowing that winter and summer tyres differ not only in tread pattern but also in construction: the rubber compound of a winter set remains flexible even in frost, whereas a summer tyre is designed for higher temperatures and offers firmer, more stable driving characteristics in warm conditions. That is precisely why it makes no sense to drive on a winter set all year round just because it "has deeper tread" - in summer it wears out faster and also performs poorly on hot road surfaces.
The 4×4×4 rule works both ways, as soon as temperatures permanently stabilise above the threshold where winter tyres cease to be advantageous in spring, it is time to switch back to summer tyres for the same reason that switching to winter tyres occurs in autumn.
Ready for winter?
PneuSwap will come to your home or workplace and fit winter tyres in 30 minutes, with no waiting at the service centre.