Is That Gap Safe? How Learner Drivers Can Make Better Decisions at Junctions

You’re waiting at a junction, looking for a suitable opportunity to join a busy road. A vehicle is approaching from your right, but it’s still some distance away. You start wondering whether there’s enough time to emerge safely. Perhaps you could make it if you move off quickly, or maybe it would be better to wait?

Meanwhile, another vehicle pulls up behind you. You’re aware that its driver is waiting, and suddenly the decision feels more urgent. You don’t want to hold anybody up, but you also don’t want to pull out in front of an approaching vehicle.

If this sounds familiar, you’re certainly not alone. Judging whether a gap in traffic is safe is one of the skills many learner drivers find particularly challenging. It’s also something that can’t be mastered simply by remembering a set of rules, because a gap that’s perfectly suitable in one situation could be completely unsuitable in another.

Learning to judge gaps involves understanding distance, speed, time, visibility and how long your own vehicle needs to complete a manoeuvre. Just as importantly, it means developing the confidence to make sensible decisions without feeling pressured by other drivers.

Why junction decisions matter

Junctions bring road users together, often travelling in different directions and at different speeds. They require drivers to gather information, assess potential conflicts and make decisions while keeping their vehicle under control.

The importance of these skills is reflected in driving test results. According to the DVSA’s published figures covering April 2024 to March 2025, failing to make effective observations at junctions was the most common reason for failing the practical car driving test in Great Britain.

The DVSA identifies several examples of this problem, including emerging into the path of an approaching vehicle, entering a roundabout when there isn’t a suitable gap and making observations too late for them to be effective.

It’s worth understanding that effective observation doesn’t simply mean looking in the correct direction. You can look both ways repeatedly and still make an unsafe decision if you’ve misunderstood the speed of an approaching vehicle or failed to notice another road user.

The real skill is recognising what you’ve seen, understanding how it could affect you and deciding whether you can complete your intended manoeuvre safely.

Distance alone doesn’t tell you whether a gap is safe

Imagine you’re waiting to turn left onto a main road. You can see a vehicle approaching from your right, approximately 100 metres away. Is that enough space to emerge?

At first glance, 100 metres might sound like a considerable distance, but we don’t yet have enough information to make a sensible decision. We also need to consider how quickly the approaching vehicle is travelling.

At 30 mph, a vehicle covers approximately 13.4 metres every second, meaning it would take around 7.5 seconds to travel 100 metres if its speed remained constant. At 60 mph, the same distance would be covered in approximately 3.7 seconds.

Although the distance is identical, the amount of time available is very different. This is why judging gaps by distance alone can be misleading, particularly on faster roads.

Of course, you won’t be calculating exact distances or counting seconds at every junction. These figures simply illustrate how speed affects the time available for a manoeuvre. With experience, you’ll become better at recognising how quickly vehicles are approaching and whether the available opportunity is suitable.

You also need to consider what your own car must do. Emerging from a junction involves more than getting the front of your vehicle into the road. You need sufficient time to move away, complete the turn, establish a suitable road position and accelerate to an appropriate speed without creating a problem for other road users.

If you’re emerging uphill, dealing with a sharp turn or joining a road with restricted space, the manoeuvre may take longer than it would on a wide, level road. A gap that works comfortably in one location might therefore be unsuitable somewhere else.

Turning left onto a busy road

Imagine you’re waiting at a Give Way junction on a residential road. The road you’re joining has a 30 mph speed limit, and a steady stream of traffic is approaching from your right.

You notice a car approaching, followed by another vehicle some distance behind it. Your first thought might be to emerge immediately after the first car passes, but before deciding, consider how quickly the second vehicle is approaching and how much time you’ll need to complete your turn.

Will you be able to emerge, straighten the steering and build up a suitable speed without causing the following driver to brake significantly? Is there a cyclist approaching that you haven’t noticed? Could parked vehicles on the road you’re joining prevent you from moving fully into the lane?

You also need to consider pedestrians, particularly anybody crossing or waiting to cross the road you’re turning into. The Highway Code advises drivers to give way to pedestrians crossing or waiting to cross at junctions.

This means that even when an approaching vehicle appears to leave you enough time to emerge, another hazard may make that opportunity unsuitable. A pedestrian crossing the road you’re entering, for example, could force you to stop partway through the turn, potentially leaving your vehicle obstructing other traffic.

Good gap assessment involves considering the whole manoeuvre and the conditions around it, rather than concentrating entirely on one approaching vehicle.

Turning right across oncoming traffic

Turning right into a side road presents a slightly different challenge because you may need to cross the path of oncoming traffic before completing your manoeuvre.

Imagine you’re waiting to turn right from a main road. An approaching vehicle appears to be travelling slowly, and you begin considering whether there’s enough time to cross in front of it.

Before committing, think about whether you’ve judged its speed correctly. Is it genuinely slowing down, or does it simply appear slow because it’s still some distance away? Could a motorcycle be approaching behind it? Are there pedestrians or cyclists crossing the road you intend to enter?

The Highway Code advises drivers to wait until there’s a safe gap in oncoming traffic and to check their mirrors and blind spots again before turning. This is particularly important because the situation around you may have changed while you’ve been waiting.

You should also consider the road you’re turning into. If it’s narrow, obstructed or occupied by another vehicle, you may not be able to complete your turn as quickly as expected.

The objective isn’t to turn at the first possible opportunity. It’s to recognise a suitable opportunity and complete the manoeuvre safely, smoothly and without forcing another road user to take avoiding action.

Judging gaps at roundabouts

Roundabouts can be particularly challenging because approaching vehicles may be travelling at different speeds or changing direction. Unlike a straightforward junction, where traffic may follow a relatively predictable path, roundabouts require you to assess several possible movements.

Suppose you’re waiting to enter a roundabout and a vehicle is approaching from your right. Its indicator suggests it’s going to leave at the exit before yours, so you begin preparing to move.

However, an indicator doesn’t guarantee that the vehicle will actually leave. It may have been activated incorrectly, or the driver may change their mind. You should consider the vehicle’s position, speed and actual movement before deciding whether your path will be clear.

You’ll also need to be aware of other vehicles that may be partially hidden, particularly motorcycles and cyclists. A large vehicle leaving the roundabout might reveal another road user following behind it.

As you gain experience, you’ll become better at understanding the pattern of traffic and recognising opportunities to enter safely. The aim is to assess what’s actually happening, rather than relying on assumptions about what another driver intends to do.

Don’t let other drivers make your decisions

One of the most common sources of pressure at junctions is the behaviour of people waiting behind you. Perhaps another driver is following closely, edging forward or sounding their horn. It’s easy to become uncomfortable and feel that you need to do something immediately.

However, the driver behind you doesn’t necessarily have the same view of the junction. They may not have noticed the motorcycle approaching, the restricted visibility or the pedestrian waiting to cross. They also don’t know how much time your vehicle needs to complete the manoeuvre safely.

Their impatience doesn’t make an unsuitable gap any safer.

Your responsibility is to make a sensible decision based on the conditions you can observe, not the expectations of somebody waiting behind you. If there isn’t enough time to emerge safely, you should wait.

This is particularly important when learning to drive because pressure from other road users can encourage rushed decisions. It’s far better to take a few additional moments to assess the situation than to emerge into a gap you’re not comfortable with simply because someone else appears impatient.

Can being too hesitant also be a problem?

Although caution is important, there’s a difference between waiting because a situation isn’t safe and waiting because you’re unwilling to make a decision despite having a clear, suitable opportunity.

Imagine you’re waiting at a junction with excellent visibility. There are no pedestrians, cyclists or obstructions affecting your manoeuvre, and approaching traffic is sufficiently far away to allow you to emerge comfortably. If you repeatedly ignore suitable gaps, you may unnecessarily delay other road users and make your own driving more difficult.

Excessive hesitation can also affect your practical driving test, although you should never take an unsafe gap simply to demonstrate confidence or avoid a fault.

Good judgement involves recognising when conditions are suitable and being prepared to act positively. Confidence should come from understanding the situation and knowing you have enough time and space, rather than taking risks.

It’s also worth remembering that even experienced drivers occasionally decide not to take a particular gap. There’s no obligation to emerge simply because a manoeuvre might be physically possible. You should be satisfied that it can be completed safely and without unnecessarily affecting others.

How can you practise judging gaps?

One useful exercise during driving lessons is to assess gaps without actually emerging into them. With your instructor’s agreement, and only where you can do so safely without unnecessarily holding up traffic, you can observe approaching vehicles and discuss whether there would be sufficient time to complete a particular manoeuvre.

For example, you might identify a vehicle approaching from the right and consider whether you could comfortably emerge ahead of it. Rather than immediately moving, you can discuss its approximate speed, how quickly the gap is closing and whether another road user would have to slow down because of you.

As the vehicle approaches, you can compare your initial judgement with how quickly it actually reaches the junction. This helps develop your understanding of speed and distance without the additional pressure of committing to a manoeuvre.

Another useful exercise is to consider what might change your decision. Perhaps a gap initially appears suitable, but a pedestrian begins crossing the road you’re entering, or an approaching vehicle accelerates. Recognising that new information may affect your decision encourages you to keep observing until you’re ready to commit.

Once you’ve committed to a manoeuvre, however, suddenly stopping in a dangerous position may create a greater risk. This is why gathering sufficient information before moving is so important.

What about junctions with restricted visibility?

Not every junction offers a clear view in both directions. Parked vehicles, buildings, walls and hedges can all make it difficult to see approaching traffic, particularly on narrow residential streets and country roads.

At a restricted junction, you may need to approach slowly, take observations from an appropriate position and carefully edge forward where necessary to improve your view. You must not simply emerge into the path of approaching traffic because you can’t see what’s coming.

The distinction between Give Way and Stop junctions is also important. At a Stop sign with a solid white line, you must stop before the line, regardless of whether the road appears clear. You can then continue making observations and move forward cautiously when it’s safe and necessary to improve your view.

The key principle remains the same regardless of the junction: gather enough information to establish that your intended manoeuvre can be completed safely before committing to it.

What will the driving examiner expect?

During your practical driving test, the examiner will want to see that you can approach junctions under control, make effective observations and recognise suitable opportunities to proceed.

They won’t expect every decision to be made instantly. Taking a little longer to assess a complicated junction can be entirely reasonable, particularly when visibility is restricted or traffic is unpredictable.

However, they will expect you to make appropriate progress when conditions allow. Emerging into the path of another vehicle and forcing its driver to brake significantly could result in a serious fault, while repeatedly missing suitable opportunities may also be assessed as a fault.

The best preparation is to gain experience of different junctions, traffic speeds and road layouts, gradually building the ability to make reliable decisions independently.

Ultimately, judging gaps isn’t about finding the smallest possible space you can squeeze into. It’s about recognising opportunities that allow you to proceed safely and smoothly, without creating unnecessary risk or disruption.

The goal isn’t to be the quickest driver at a junction. It’s to understand when it’s safe to go, and to be confident enough to act when that opportunity arises.