Can Car Tyres Melt in Hot Weather? Tyre Melting Point Explained

Normal UK summer temperatures will not make a healthy car tyre simply melt. However, heat does affect tyres. As temperatures rise, tyre pressure increases and heat can add stress to tyres that are already worn, damaged, incorrectly inflated or heavily loaded.

So, can tyres actually melt in hot weather, and what is the melting point of a car tyre? The answer is more complicated than a single temperature figure.

Can Car Tyres Melt in Hot Weather?

No, not under normal UK summer driving conditions.

A modern road tyre is made from a combination of rubber compounds, reinforcing materials, steel or textile components and other materials. It is designed to operate at temperatures considerably higher than the surrounding air temperature without turning into liquid.

That means even during a particularly hot UK day, you should not expect your car tyres to melt simply because the outside temperature has risen.

Heat can still affect them. The tyre itself becomes hotter while driving because of friction, flexing and contact with the road. The amount of heat generated depends on factors including speed, load, tyre pressure, road temperature and how the vehicle is being driven.

This is why a tyre that is already damaged or incorrectly inflated deserves more attention during very hot weather.

What Is the Melting Point of a Car Tyre?

There is no single tyre melting point that can be given for every car tyre.

This is an important distinction because a tyre is not made from one type of rubber. Different parts contain different compounds and materials, and vulcanised rubber does not behave like a simple thermoplastic that reaches one temperature and turns into liquid.

At sufficiently high temperatures, rubber compounds can soften, deteriorate and eventually break down or thermally decompose rather than simply melting at one fixed temperature.

The old idea that a car tyre has a specific melting temperature is therefore misleading. A tyre can suffer serious heat-related damage long before there is any question of the entire tyre becoming liquid.

What Happens to Tyres When They Get Very Hot?

Heat affects a tyre in several ways.

As the temperature of the air inside the tyre increases, its pressure also rises. The tyre itself can become significantly hotter than the outside air during driving because it continually flexes and generates heat.

A tyre in good condition is designed to cope with this. Problems are more likely when heat is combined with another issue, such as:

• incorrect tyre pressure

• excessive wear

• cuts, cracks or other damage

• overloading the vehicle

• prolonged high-speed driving

• abnormal or uneven tyre wear

This is why hot weather is a good reason to check your tyres rather than a reason to assume they are going to melt.

What Happens to Tyre Pressure in Hot Weather?

Tyre pressure increases as the temperature of the air inside the tyre rises.

You may therefore see a higher pressure reading after the car has been driven or during particularly warm weather. That does not automatically mean you should let air out.

Check pressures when the tyres are cold and use the pressure recommended by the vehicle manufacturer. The correct figure can normally be found in the vehicle handbook or on the manufacturer's tyre-pressure information label.

If you check a tyre when it is hot, allow for the fact that its pressure will be higher than when cold.

Also Check: Hidden Costs of Owning a Car

Why Do Roads Sometimes Look Like Tyres Are Melting?

A road that looks unusually black, shiny or sticky during very hot weather does not necessarily mean car tyres are melting onto it.

Road surfaces contain bitumen, which can soften as temperatures rise. In extreme heat, bitumen can become more noticeable at the surface, particularly where the road has already experienced wear.

Tyres also leave rubber particles on the road through normal wear. These processes can contribute to the dark appearance of a road surface, but it is inaccurate to describe the whole road as being covered in melted tyre rubber.

If you notice a sticky road surface during a hot spell, drive appropriately for the conditions and pay attention to changes in grip or the condition of the road.

Can Hot Weather Damage Your Tyres?

Hot weather alone should not cause a healthy road tyre to fail, but high temperatures can increase the stress placed on a tyre.

This matters particularly if the tyre already has a problem.

Before a long journey in hot weather, check for:

• cuts or cracks in the sidewall

• bulges or lumps

• unusual tread wear

• objects embedded in the tyre

• incorrect tyre pressure

• insufficient tread depth

A bulge in the sidewall is particularly important because it can indicate damage to the tyre's internal structure. It should not be ignored or treated as something that will disappear when the tyre cools down.

The same applies to unusual vibration, repeated pressure loss or visible damage. Have the tyre inspected rather than continuing to drive on it.

How to Check Your Tyres in Hot Weather

You do not need to do anything complicated because the temperature has risen.

Before a long trip:

1. Check all four tyre pressures when the tyres are cold.

2. Use the vehicle manufacturer's recommended pressures.

3. Inspect the sidewalls and tread for damage.

4. Check the tread for excessive or uneven wear.

5. Make sure the vehicle is not overloaded.

6. Check the spare tyre if your vehicle has one.

7. If a tyre has a bulge, serious damage or is losing pressure, get professional advice before driving.

In Great Britain, the legal minimum tread depth for cars is 1.6mm across the central three-quarters of the tread and around the entire circumference. In practice, you should not wait until a tyre reaches the legal limit if its condition or performance has already deteriorated.

Also Read: Car Maintenance Checklist

Should You Use Summer or Winter Tyres in Hot Weather?

Summer and winter tyres are designed with different compounds and tread patterns for different conditions.

Summer tyres are designed to perform in warmer conditions, while winter tyres are designed to provide better performance at lower temperatures and in conditions such as cold, wet roads, snow and ice.

That does not mean a winter tyre will melt during a UK summer. However, winter tyres can wear more quickly in warmer conditions because their compounds are designed for lower temperatures.

There is also no need to assume that every UK driver must switch to summer tyres whenever temperatures rise. The right choice depends on the vehicle, tyres fitted, driving conditions and where and how the car is used.

For most drivers, correct pressure, good tread and a tyre that is in good condition are more important than worrying about the tyre reaching its "melting point".

When Should You Replace a Car Tyre?

A tyre may need replacing before it reaches the legal tread limit.

Look for signs such as:

• tread approaching the legal minimum

• uneven or abnormal wear

• cuts or cracks

• sidewall bulges

• repeated loss of pressure

• damage that cannot be safely repaired

• vibration or other changes that may indicate a tyre or wheel problem

Tyre age can also be relevant, particularly where a vehicle has covered relatively few miles. Rubber deteriorates over time, so a tyre that looks unused should not automatically be assumed to be in perfect condition.

If you are unsure about a tyre's condition, have it checked by a qualified tyre professional.

If You're Replacing Your Car, What Happens to the Tyres?

If you're replacing your car because it is becoming expensive to maintain, tyre condition is one of several costs worth considering alongside servicing, insurance, fuel and unexpected repairs.

You may also be deciding whether to buy your next car or personal car leasing. The two options work differently. With a leased car, you do not normally own the vehicle during the agreement, but you are still responsible for looking after it in line with the lease terms. This can include keeping the tyres roadworthy and replacing damaged or worn tyres where required.