Have you been offered run flat tyres for your car and want to know the pros and cons? Maybe you’ve just heard of them and you’re interested to know more about how run flat tyres work, what maintenance they require, and if they’re actually worth the extra money you’ll pay for them. If so, check out our complete guide below.

What are run flat tyres?

Run flat tyres are designed to remain safe and functional for a limited time with no air pressure. That means, in the event of a puncture, you can continue driving for around 50 miles at speeds of up to about 50mph after a puncture, without having to change the tyre — which could be enough to get you home, or to a garage.

How do run flat tyres work?

Unlike conventional tyres, which require air to stay hard, run flat tyres have a reinforced sidewall, meaning they stay rigid without any air pressure.

The reinforced outer shell of run flat tyres keeps the rubber in place without air, supporting the car as you continue your journey. However, the sidewall isn’t designed to be permanent, and is only recommended for around 50 miles of additional driving after the tyre has deflated.

How to identify run flat tyres

Usually you can identify if your tyre is a run flat tyre by checking the markings. The sidewall of the tyre may have the following markings or labels:

  • Standard tyre markings: Look for terms like ‘Run-Flat’, SSR (Self-Supporting Run-flat), RFT (Run-Flat Technology) or other similar abbreviations on the sidewall.
  • Manufacturer designations: Some tyre manufacturers will have their own branded terms that let you know it’s a run flat tyre. For example, Bridgestone uses the term ‘DriveGuard’.
  • ISO symbol: Some tyres feature markings such as ‘Run Flat’, ‘RFT’, ‘SSR’ (Self-Supporting Runflat) or ‘RSC’ (Run-Flat System Component). The exact markings can differ depending on the tyre manufacturer.

You can also check your owner’s manual or the car spec if you’re unsure if your vehicle has run flat tyres.

Do I need run flat tyres?

Run flat tyres aren’t suitable for every vehicle, so it’s important first to check that your car is a match. However, if your car can have run flat tyres, there are a few benefits but also some important considerations too.

Run flat tyres are designed to maintain stability and allow continued driving after a sudden loss of pressure, helping drivers maintain control following a puncture. These tyres can also save space in the boot, as you don’t need a spare wheel. You also won’t be stranded at the side of the road when you get a puncture, as run flat tyres will allow you to drive up to 50 miles after the puncture occurs.

Many newer cars will have run flat tyres fitted as standard, giving peace of mind and added security. However, it can depend on your personal preference and budget whether you really need them.

How does the driver know when their run flats have a puncture?

Most vehicles designed to use run flat tyres are fitted with a tyre pressure monitoring system (TPMS) to alert the driver when pressure is lost. Without a TPMS system, it would be almost impossible to detect a puncture, given that run flat tyres will continue to work even when they’re deflated.

Most TPMS systems display an alert on the centre console, reminding the driver that they should stop driving after 50 miles and seek a tyre repair or replacement.

Do run flat tyres last as long as normal tyres?

Run flat tyres use similar rubber compounds to standard tyres, so their lifespan is often comparable, although wear can vary depending on driving style, vehicle weight and tyre design.

To keep your run flat tyres in good condition, check their pressure, depth and condition every fortnight. This will ensure you get maximum life out of your tyres before having to replace them.

Can you repair run flat tyres?

Run flat tyres aren’t repairable. That’s because, once they’ve been driven on, they lose their structural integrity, making them unsuitable for puncture repair. If they are patched up, it’s highly likely they’ll puncture again down the line due to uneven wear and loss of rigidity.

And that’s their biggest drawback compared to conventional tyres, which can often be repaired reasonably cheaply after a puncture (provided the hole isn’t in the sidewall). Given the expense of buying run flat tyres in the first place, each puncture could end up costing a small fortune.

Are run flat tyres expensive?

Run flats are typically more expensive than standard tyres, often costing around 20-40% more depending on the brand and size.

Can run flat tyres be fitted at home?

Run flat tyres usually require specialist tyre-changing equipment due to their reinforced sidewalls. For this reason, they are usually fitted by professional tyre centres or mobile tyre-fitting services.

Can you mix run flat tyres with normal tyres?

Although there are no specific laws preventing you from mixing run flat and standard tyres, most manufacturers advise against it. At the very least, tyres on the same axle should always be the same type.

Are run flat tyres worth it?

While run flat tyres are typically more expensive, they can be more helpful should you get a puncture. It means you don’t have to wait on the hard shoulder or by the side of the road, however if you have good breakdown cover then they may not be necessarily essential.

If you drive regularly on motorways, having run flat tyres and a tyre pressure monitoring system (TPMS) could reduce tyre-associated incidents such as blowouts. This is because driving at higher speeds makes it harder to tell if your car has picked up a puncture.

Do run flat tyres affect insurance?

If your car comes with run flat tyres as standard, this has no effect on your vehicle insurance. However, if you decide to change your tyres either from or to run flats, it’s best practice to notify your insurer.

You should also check your vehicle’s warranty if you’re changing your tyres just in case it’s affected.

If you don’t fancy paying through the nose for a car with run flat tyres, Holts Tyreweld Emergency Puncture Tyre Repair offers the next best thing. In the event of a puncture, this innovative DIY product quickly seals and re-inflates your tyre — allowing you to get to a garage without having to mess around with a spare wheel.

To find out more about our DIY car care range, visit our homepage.