If there's a nail or screw in your tyre, don't pull it out. Check whether the tyre is holding air, move the car only as far as you need to reach somewhere safe, and get the tyre inspected. The AA's advice is blunt: if something like a nail has pierced the tyre, "don't try to take it out", because that could make the hole bigger (AA puncture guide).
Whether you end up with a repair or a new tyre comes down to three questions: where the nail is, how big the hole is, and whether the tyre has been run low. The decision table below answers all three in one place, using the repair rules set out in BS AU 159 and the guidance from TyreSafe and the British Tyre Manufacturers' Association (BTMA). After that you'll find what to do in the first few minutes, the mistakes that turn a repairable tyre into a scrap one, and how a proper repair is actually carried out.
Nail or screw in your tyre: what to do first
The first few minutes decide whether a nail stays a small job. Work through these in order:
- Leave the nail in. While it's in the hole it often slows the air loss. Pulling it out can turn a slow leak into a flat and, as the AA warns, can make the hole bigger.
- Look and listen. A hiss, a tyre that looks lower than the others, or a tyre pressure warning on the dash all tell you air is escaping.
- Check the pressure against the figure on the door pillar or fuel flap. If it's close to normal, the nail is sealing for now. If it has dropped a lot, treat it as a flat.
- Only move the car if you need to. TyreSafe says you may be able to drive a short distance on a punctured tyre, "but only at low speeds and for the minimum distance needed to reach a garage or safe location" (TyreSafe). If the tyre is going flat, don't drive on it; see is it safe to drive on a flat?
- Note where the nail is. A quick photo showing whether it sits in the middle of the tread, near the edge or in the sidewall helps a fitter tell you on the phone whether a repair is likely.
- Arrange an inspection. A permanent repair needs the tyre off the wheel, so this is a job for a fitter, not the driveway.
On a motorway? Don't stop on the hard shoulder to look at the tyre. If the car is still driving safely, leave at the next junction or services and stop somewhere away from traffic. If it isn't, pull onto the hard shoulder or into an emergency area and get everyone out on the verge side, behind the barrier. If you're in danger, call 999, and you can reach National Highways on 0300 123 5000 (National Highways breakdown advice).
Can a nail in a tyre be repaired? The decision table
A nail in the central part of the tread is usually repairable. A nail in the shoulder or sidewall never is. BS AU 159 is the British Standard UK tyre fitters work to. The BTMA's guidance for the trade says to "repair in area 'T' only", a measured zone across the middle of the tread, with a maximum hole of 6mm (BTMA). TyreSafe sums the zone up as "the central ¾ of the tyre" and adds that damage "close to or on the tyre sidewall" can't be repaired (TyreSafe).
| Where the nail or screw is | What else is true | Repairable under BS AU 159? | What happens next |
|---|---|---|---|
| Middle of the tread | Hole 6mm or less, tyre not run flat | Yes | Tyre comes off the wheel, is checked inside and gets a combination patch-plug repair |
| Outer tread, near the edge of the repair zone | Hole 6mm or less | Usually | The fitter measures the zone for that tyre size. If the damage reaches beyond it, the tyre is replaced |
| Shoulder, where the tread turns into the sidewall | Any size | No | New tyre in the same size, load index and speed rating |
| Sidewall | Any size | No | New tyre. See is sidewall damage repairable? |
| Middle of the tread | Hole bigger than 6mm, or a cut rather than a hole | No | New tyre |
| Middle of the tread | Tyre has been driven flat or very low | Only if the inside is undamaged | The internal inspection decides. Heat damage inside the tyre means a replacement |
| Middle of the tread | A new repair would overlap an old one | No | BTMA: no limit on the number of repairs "provided that repair patches do not overlap" |
| Run-flat tyre, any position | Depends on the tyre maker | Maker's policy | TyreSafe says to consult the tyre manufacturer. See the run-flat section below |
| Anywhere | Tread already close to 1.6mm | Not worth it | The tyre is near the legal limit, so a new tyre makes more sense |
Two points people often get wrong. First, a screw is treated exactly like a nail: its thread doesn't change the rules, only the position and hole size do. Second, speed rating doesn't rule out a repair on its own. The BTMA states that "tyres repaired to BS AU 159 are able to operate at their original speed and load capabilities." If you're weighing up the borderline cases, tyre repair vs replacement goes further, and can a puncture be repaired? covers other kinds of damage.
On tread depth, the law requires at least 1.6mm "across the central three-quarters of the breadth of the tread and around the entire circumference" (Highway Code, Annex 6). TyreSafe notes that 3mm is the minimum commonly advised by tyre and safety experts (TyreSafe tread depth), so if the tyre is close to that already, spending money on a repair is poor value.
What not to do with a nail in your tyre
Most tyres that could have been repaired are lost to one of these mistakes.
- Don't pull the nail out "to see how bad it is". You'll learn nothing a fitter can't see, and you may lose the air and the repair.
- Don't treat a plug kit or sealant as the fix. TyreSafe is clear: "Neither externally applied plug repairs, nor liquid sealants can be considered to be a permanent repair" (TyreSafe). A string plug seals the tread from outside without anyone checking the inside of the tyre.
- Don't drive far or fast on it. Michelin explains that driving on a flat or under-inflated tyre damages the structure inside, and once that happens the tyre "cannot be repaired, even if the puncture was in the tread" (Michelin tyre repair advice). Temporary fixes come with their own limits: a sealant kit or space-saver spare is usually marked with a maximum speed, commonly 50mph, so follow the instructions on the kit or the wheel.
- Don't let anyone repair it with the tyre still on the wheel. TyreSafe says permanent repairs "can only be carried out following removal of the tyre from the wheel to allow a thorough inspection internally as well as externally."
- Don't accept an inner tube in a tubeless tyre as a repair. The BTMA lists inner tubes fitted to tubeless tyres among the methods that are not acceptable.
- Don't ignore a slow loss. A nail that holds today can loosen tomorrow. If one tyre keeps needing air, read slow puncture causes and fixes.
Can you drive with a nail in your tyre?
Only as far as you need to reach somewhere safe, slowly, and only while the tyre still holds air. How the tyre behaves tells you what to do:
| What the tyre is doing | What to do |
|---|---|
| Pressure normal, no hiss | The nail is sealing for now. Avoid long or fast journeys and get it inspected soon |
| Losing air slowly | A short, gentle drive to a safe place to park, then have it looked at where the car is |
| Visibly low, flat or dropping fast | Don't drive on it. Driving on a flat destroys the structure and ends any chance of a repair |
| Warning light on, pressure unknown | Stop when safe and check the pressures |
There's no safe number of days to leave a nail in. It can work loose, and a tyre losing air slowly is running under-inflated between top-ups, which heats and flexes the casing. Treat it as a job for this week, not next month.
How a BS AU 159 repair is done
A permanent repair is done from inside the tyre, with the tyre off the wheel. That's the difference between a repair and a plug. A fitter working to BS AU 159 follows these steps:
- Remove the wheel and take the tyre off the rim. This is the step TyreSafe says a permanent repair can't skip.
- Inspect the inside. The inner liner is checked for damage from the nail, for signs the tyre has been run low and for any second puncture.
- Measure the repair zone and the hole. If the damage is outside the zone or bigger than 6mm, the job becomes a replacement.
- Remove the object and prepare the hole so the repair bonds to sound rubber.
- Fit a combination patch-plug. Michelin describes this as a mushroom-style repair that fills the hole and seals the inside in one piece, and says wicks and patches used alone are "strongly disadvised".
- Refit, inflate to the car's figure and balance the wheel, then tighten the wheel nuts to the manufacturer's torque.
Our vans carry tyre fitting and wheel balancing equipment, so all of this happens where the car is parked. See our mobile puncture repair page for how a visit works.
Run-flat, EV and foam-lined tyres
The same repair rules apply to run-flat, EV and foam-lined tyres, with a few extra checks.
- Run-flat tyres. TyreSafe advises that "for repairs to self-supporting run flat tyres, consult the relevant tyre manufacturer", and warns that driving on a deflated run-flat "can weaken and permanently damage it, making the tyre both unsuitable and unsafe to repair" (TyreSafe). Policies differ: Michelin says its run-flats can be repaired only once, under the same conditions as a standard tyre (Michelin run-flat advice). If the warning light has been on for a while, plan for a replacement. We supply and fit run-flat tyres.
- Tyres with a foam layer inside. Many electric and premium cars use tyres with noise-reducing foam bonded inside. Tell us on the call if your tyres have it, so the fitter comes prepared.
- Electric cars. The rules for position and hole size are the same. Heavier cars make driving on a low tyre more damaging, so don't push on.
- Tyre pressure sensors. Most cars clear the warning after the repair and a short drive. If yours doesn't, the system may need resetting.
Get the nail dealt with where the car is
You don't need to drive a punctured tyre to a garage. Rescue Tyres is a fully mobile service, and we come to your home, workplace or a safe spot off the road across London and the Home Counties, from our base in Brent Cross; further out, we tell you on the call whether we can reach you. Our puncture repairs follow BS AU 159. If the nail is outside the repair zone, we source a new tyre in your car's size, whether you want budget, mid-range or premium.
- Price confirmed on the call before any work starts
- A realistic arrival time agreed on the call
- Evenings, nights, weekends and bank holidays when the diary allows, at the same price as a weekday job
Send us a photo of the nail on WhatsApp or call 07473 720871.
Sources
- The AA, How to repair a tyre puncture
- TyreSafe, Punctures and puncture repairs
- TyreSafe, Tyre repair and spares
- British Tyre Manufacturers' Association, BS AU 159 guidance for tyre industry professionals
- Michelin, Tyre repair
- Michelin, Runflat tyres
- GOV.UK Highway Code, Annex 6: vehicle maintenance, safety and security
- TyreSafe, Tread depth
