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Rules of the road · about 2 min read

Vehicle dimensions, loads and projections

Understand the rule, its conditions and how to apply it

What you will learn

  • Explain the purpose of this rule.
  • Apply the procedure and recognise its limitations.

Purpose and essential terms

A load changes the vehicle’s dimensions, visibility and behaviour. Overall height is measured from ground level to the highest part of the vehicle or its load. Overall length includes the full combination where applicable. Know the actual measurements before approaching a restricted route or bridge.

The reference maximum height is 4.3 metres for most vehicles and 4.65 metres for double-deck buses. Width is generally 2.5 metres, with 2.6 metres for the specified buses and goods vehicles of at least 12,000 kg GVM. A lower signed clearance on the route still applies.

Key idea: A load changes the vehicle’s dimensions, visibility and behaviour.

How to apply the rule

Secure goods so they cannot spill, fall, drag on the road or obstruct the driver’s forward, side or mirror views. The manual lists length limits of 18.5 metres for articulated vehicles, 22 metres for combinations, 12.5 metres for other vehicles and different limits for specified trailers. It also limits roof-load height on motorcars and requires suitable container fastening.

General light/heavy-vehicle load projections may not exceed 300 mm beyond the front or 1.8 metres beyond the rear. A load extending more than 150 mm to the side or 300 mm to the rear requires a red flag of at least 300 × 300 mm by day, and prescribed reflectors at night or in poor visibility. Marking does not authorise a projection beyond the limit.

Key idea: Check the overall dimensions, route clearance and all projection limits.

Conditions and easily confused points

Motorcycle projection rules are measured differently: the manual lists 600 mm ahead of the front axle, 900 mm behind the rear axle, 450 mm either side of the wheels and 300 mm outside a sidecar wheel. Use securely attached suitable carriers and do not impair control.

Passenger conveyance is not a load-securing permission. The manual describes enclosure heights for people on goods vehicles, but these do not make unsafe or otherwise prohibited carriage lawful. It prohibits passengers in a caravan. Current vehicle-specific passenger and permit rules need checking.

Key idea: Apply the full rule to the actual vehicle, road and conditions.

Worked road situation

A secured load extends 400 mm beyond the rear of a light vehicle.

  1. Check the overall dimensions, route clearance and all projection limits.
  2. Because the rear projection exceeds 300 mm, provide the prescribed daytime flag or applicable reflectors for conditions.
  3. Confirm the load cannot shift, spill, hide lamps or obstruct the view.

Quick recap

  • Check the overall dimensions, route clearance and all projection limits.
  • Because the rear projection exceeds 300 mm, provide the prescribed daytime flag or applicable reflectors for conditions.
  • Confirm the load cannot shift, spill, hide lamps or obstruct the view.

Practice questions on vehicle dimensions, loads and projections

1 What must be included when checking a vehicle’s overall height?

  1. The vehicle and its load
  2. The cab only
  3. The empty vehicle only
Show the answer

Answer A: The vehicle and its load

Check the vehicle and load together. The reference manual gives a 4.3 m height limit for most vehicles and 4.65 m for double-deck buses. Its general width limit is 2.5 m, with 2.6 m for specified buses and goods vehicles of 12,000 kg GVM or more. Length limits depend on vehicle class: 18.5 m for articulated vehicles and 22 m for combinations. Loads must be secured without obscuring vision, spilling or dragging. Goods may project at most 300 mm beyond the front or 1.8 m beyond the rear under the general light/heavy-vehicle rules. A load projecting over 150 mm to the side or 300 mm to the rear needs a 300 × 300 mm red flag by day and prescribed reflectors at night or in poor visibility. The manual describes an enclosure at least 350 mm above the seated surface or 900 mm above the standing surface when people are carried on goods vehicles. This is not permission to carry passengers for reward or in unsafe conditions. It prohibits passengers in a caravan. Check current regulations and your specific vehicle before carrying loads or passengers.

Memory tip: Read the full rule, including its conditions and exceptions.

All vehicle codes

2 How must goods be carried?

  1. Securely contained or fastened against dislodging or spilling
  2. Dragging along the road
  3. Loose so they are easy to unload
Show the answer

Answer A: Securely contained or fastened against dislodging or spilling

Check the vehicle and load together. The reference manual gives a 4.3 m height limit for most vehicles and 4.65 m for double-deck buses. Its general width limit is 2.5 m, with 2.6 m for specified buses and goods vehicles of 12,000 kg GVM or more. Length limits depend on vehicle class: 18.5 m for articulated vehicles and 22 m for combinations. Loads must be secured without obscuring vision, spilling or dragging. Goods may project at most 300 mm beyond the front or 1.8 m beyond the rear under the general light/heavy-vehicle rules. A load projecting over 150 mm to the side or 300 mm to the rear needs a 300 × 300 mm red flag by day and prescribed reflectors at night or in poor visibility. The manual describes an enclosure at least 350 mm above the seated surface or 900 mm above the standing surface when people are carried on goods vehicles. This is not permission to carry passengers for reward or in unsafe conditions. It prohibits passengers in a caravan. Check current regulations and your specific vehicle before carrying loads or passengers.

Memory tip: Read the full rule, including its conditions and exceptions.

All vehicle codes

3 May a load obscure the driver’s view?

  1. No
  2. Yes, in daylight
  3. Yes, if a passenger can see
Show the answer

Answer A: No

Check the vehicle and load together. The reference manual gives a 4.3 m height limit for most vehicles and 4.65 m for double-deck buses. Its general width limit is 2.5 m, with 2.6 m for specified buses and goods vehicles of 12,000 kg GVM or more. Length limits depend on vehicle class: 18.5 m for articulated vehicles and 22 m for combinations. Loads must be secured without obscuring vision, spilling or dragging. Goods may project at most 300 mm beyond the front or 1.8 m beyond the rear under the general light/heavy-vehicle rules. A load projecting over 150 mm to the side or 300 mm to the rear needs a 300 × 300 mm red flag by day and prescribed reflectors at night or in poor visibility. The manual describes an enclosure at least 350 mm above the seated surface or 900 mm above the standing surface when people are carried on goods vehicles. This is not permission to carry passengers for reward or in unsafe conditions. It prohibits passengers in a caravan. Check current regulations and your specific vehicle before carrying loads or passengers.

Memory tip: Read the full rule, including its conditions and exceptions.

All vehicle codes

4 What daytime marker does the manual prescribe for a load projecting over 300 mm to the rear?

  1. A white handkerchief
  2. A red flag at least 300 × 300 mm
  3. No marker
Show the answer

Answer B: A red flag at least 300 × 300 mm

Check the vehicle and load together. The reference manual gives a 4.3 m height limit for most vehicles and 4.65 m for double-deck buses. Its general width limit is 2.5 m, with 2.6 m for specified buses and goods vehicles of 12,000 kg GVM or more. Length limits depend on vehicle class: 18.5 m for articulated vehicles and 22 m for combinations. Loads must be secured without obscuring vision, spilling or dragging. Goods may project at most 300 mm beyond the front or 1.8 m beyond the rear under the general light/heavy-vehicle rules. A load projecting over 150 mm to the side or 300 mm to the rear needs a 300 × 300 mm red flag by day and prescribed reflectors at night or in poor visibility. The manual describes an enclosure at least 350 mm above the seated surface or 900 mm above the standing surface when people are carried on goods vehicles. This is not permission to carry passengers for reward or in unsafe conditions. It prohibits passengers in a caravan. Check current regulations and your specific vehicle before carrying loads or passengers.

Memory tip: Read the full rule, including its conditions and exceptions.

All vehicle codes

More rules of the road chapters

Sources: NaTIS Rules of the Road, PDF pp. 29–31, sections 6.30–6.36; iDriving K53 manual, PDF pp. 91–102 (comparison; incomplete text extraction checked against official reference).

AceK53 is an independent study aid based on public road traffic manuals and is not an official test. Always confirm requirements with your driving licence testing centre.