Factsheet 53 — July 2005

Printable version

Overdimension vehicles and loads

About the 'Vehicle Dimensions and Mass' Rule

This factsheet summarises some requirements of Land Transport Rule: Vehicle Dimensions and Mass 2002.

For full information, obtain a copy of the Rule (available in print from bookshops that sell legislation and some libraries). If there are any differences between the requirements described here and those described in the Rule, follow the Rule.

What is an overdimension vehicle or load?

An overdimension (or oversize) vehicle or load exceeds the maximum dimensions allowed for standard vehicles.

• If you need information on the maximum sizes for standard motor vehicles, see Factsheet 13a Heavy rigid vehicles and Factsheet 13c Trailers: Full, semi, simple, pole, A-train and B-train, or contact Land Transport New Zealand's helpdesk: (freephone) 0800 699 000.

Overdimension vehicles or loads are only allowed if they can't be made smaller: they must be indivisible. (An indivisible load is a load that can't (without an unreasonable amount of effort or expense, or the risk of damage to the load) be divided into two or more sections for road transport.)

Construction machinery should be loaded so it fits within standard dimension limits, if possible.

There are special operating conditions that overdimension vehicles or loads must meet, based on the size of the vehicles and loads. There are four size categories — 1, 2, 3 and 4 — each larger than the previous one. This factsheet concentrates on the most common size categories, Categories 1 and 2.

• If you need information on Category 3 or Category 4 overdimension vehicles and loads, contact the Overdimension Permit Issuing Agency (OPIA) Helpdesk: freephone 0800 OVERSIZE (0800 683 774) or fax 06 953 6313.

Note: You need to contact your nearest regional office of Transit New Zealand if your load is overweight — that is, exceeds the mass (weight) limits in Factsheet 13 Vehicle dimensions and mass.

How to use this factsheet

1. First, read about types of overdimension vehicles and loads.

2. Then study the general operating conditions that all overdimension vehicles must comply with.

3. Work out which category your vehicle (including the load) is in.

4. Determine whether you need a permit.

5. You'll need to comply with some specific operating requirements for Category 1 and Category 2 overdimension vehicles.

6. Make sure you carry this factsheet in your vehicle, so you can refer to it.

Types of overdimension vehicles and loads

Standard-sized motor vehicles carrying overdimension loads

Example: A rigid truck that doesn't normally exceed the standard dimension limits but is being used to transport an overwidth tank or long load.

A standard motor vehicle may be used to transport an overdimension load as long as the load is indivisible, and is loaded in a way that minimises its width. (Unless the load's height or instability, or both, makes it necessary to transport the load sideways).

A standard motor vehicle may transport more than one overdimension load, if the loads:

• aren't wider than 2.5 metres if they're loaded side by side
• aren't higher than 4.25 metres if they're loaded one above the other
• aren't longer than the standard length or rear overhang limits for that vehicle if they're loaded one behind the other.

These combination motor vehicles can't exceed the standard rear overhang or overall length limits:

• A truck and simple trailer
• A truck and full trailer
• An A-train truck
• A B-train truck.

Specialist overdimension vehicles

Example: Chip spreaders, forklifts, mobile cranes, snow ploughs etc.

Specialist overdimension vehicles aren't primarily designed to transport overdimension or overweight loads, but they can exceed the limits for standard vehicles if:

• the vehicle's primary purpose is to carry out a specialist function that requires overdimension equipment, and
• dismantling the vehicle's overdimension equipment would make the vehicle unusable for its intended purpose, or
• it would take more than four hours to dismantle the equipment.

A specialist overdimension motor vehicle may transport a divisible load, but it can't exceed the maximum standard dimension limits if those limits can be complied with by reducing the size of the vehicle's divisible load.

Overdimension vehicles designed for overdimension or overweight loads

Examples: Low loaders, three or four rows of eight transporters, multi-axle house trailers, platform trailers.

The following three scenarios show how these vehicles, commonly referred to as overdimension transporters, can be loaded.

1. Overdimension transporter carrying an overdimension load

An overdimension transporter can carry an overdimension load if the load:

• is indivisible, and
• is loaded in a way that minimises its width (unless the load's height or instability (or both) makes it necessary to transport the load sideways).

An overdimension transporter may transport more than one overdimension load if:

• side by side, the total width isn't greater than 2.5 metres
• one above the other, the total load isn't higher than 4.25 metres
• one behind the other, the length, front or rear overhang limits of a standard vehicle aren't exceeded.

2. Overdimension transporter carrying an overdimension load and a divisible load

If an overdimension transporter is carrying an overdimension load and a divisible load (general freight), the overdimension transporter must be reduced to the smallest dimension practicable to carry the indivisible load. This means widening trailers must be closed to their narrowest width, and tromboning trailers must be reduced to their shortest forward distance.

This means widening trailers must be closed to their narrowest width, and tromboning trailers must be reduced to their shortest forward distance.

Overdimension transporters may transport divisible goods if the goods:

• side by side, don't overhang the deck and the deck has been reduced to its smallest width
• one above the other, aren't higher than 4.25 metres, and
• one behind the other, don't overhang the deck and the deck has been reduced to its shortest length.

3. Overdimension transporter carrying divisible load (general freight) only

If an overdimension transporter is only carrying a divisible load (general freight), (ie, it isn't transporting an overdimension load), the transporter must be reduced to the smallest dimension practicable. Widening trailers must be closed to their narrowest width, and tromboning trailers must be reduced to their shortest forward distance.

An overdimension transporter may transport divisible goods if:

• one direction of the vehicle's journey requires the overdimension vehicle to transport an overdimension load, or
• the weight or instability of the divisible load requires the use of the overdimension motor vehicle

If the two points above are true, then the three points below must also be met:

• Side by side, the goods don't overhang the deck and the deck has been reduced to its smallest width, and
• One above the other, the goods aren't higher than 4.25 metres, and
• One behind the other, the goods don't overhang the deck and the deck has been reduced to its smallest length.

General operating requirements that apply to all overdimension vehicles

If you're the driver of an overdimension vehicle, you should be sure your vehicle can fit along the proposed route before starting out. Drive along the route in daylight in a standard-sized vehicle first, checking for places where the overdimension vehicle may find it difficult to pass. If you intend to carry a high load, look out for overhead wires, signs, lights, trees, bridges and tunnels.

Damage

An overdimension vehicle must not interfere with or damage any traffic control device, bridge, tunnel or other structure (including wires, cables, banners or any other lawful construction). It must not damage trees or other foliage without the permission of the owner. If a traffic sign has to be moved so the vehicle can safely pass, the sign must be correctly replaced immediately afterwards. The operator of the overdimension vehicle is responsible for any damage.

Consideration for other road users

An overdimension vehicle must be operated with due consideration for other road users. Other road users must be allowed to pass the vehicle at the earliest safe opportunity.

Overdimension requirements for excess height

If your vehicle or load exceeds 4.25 metres in height, you must comply with these conditions.

Height (m)	Operating conditions
4.25–5.0	Need written permission from owner of any overhead obstruction that the vehicle can't clear safely. Need written approval from relevant rail service operator, if the vehicle travels over a railway level crossing that doesn't cross a state highway, and the vehicle exceeds the height shown on an electrified railway safe height sign. For loads over 4.8 metres, must use a vehicle with a deck height less than 1.3 metres above the road.
Over 5–6.5	Need to meet all of the above operating conditions. Need a permit from OPIA*. A vehicle with a deck height less than 1.3 metres above the road must be used. Need written permission from the owner of overhead wires or cables that the vehicle travels under.
Over 6.5	Need written approval from the Director of Land Transport. Apply to OPIA*.

* To contact OPIA's Helpdesk, freephone 0800 683 774 or fax 06 953 6313.

The operator is responsible for making sure there are enough pilots to deal with the excess height. This will depend on what traffic management (if any) is needed to get around overhead obstructions.

Lighting during the day

During daylight hours, overdimension vehicles must travel with their headlights on low beam.

Overdimension vehicles must display a flashing amber light if they're more than 3.7 metres wide.

Overdimension vehicles must display a flashing amber light if they're being piloted by a pilot vehicle.

Lighting during the hours of darkness

During the hours of darkness, all overdimension vehicles must be clearly visible (in clear weather) from at least 200 metres away.

Overdimension vehicles must display a flashing amber light.

If a load is being carried, there must be steady white or amber lights at the front and steady red or amber lights at the rear. These lights must have an area of at least 50 square centimetres and be positioned so approaching traffic can determine the size of the load and safely get past it. If the load overhangs the deck of the vehicle sideways, these lights must be spaced approximately one metre apart across the lowest part of the load and at the widest parts of the load.

Overdimension vehicles must have side marker lamps spaced approximately 3 metres apart — amber colour to the front and red to the rear.

Visibility

An overdimension vehicle must not travel on a road if fog, heavy rain, hail or other factors restrict visibility to less than 500 metres. If visibility reduces to less than 500 metres after the journey starts, the vehicle must stop clear of moving traffic as soon as possible, and stay there until visibility improves (ie more than 500 metres).

Alerting emergency services

The operator of an overdimension vehicle must notify local emergency service personnel in any area where the vehicle or its load is likely to restrict a route in a way that would significantly delay emergency services.

Route restrictions

An overdimension vehicle must:

• where available, use a route designated by a road controlling authority as suitable for overdimension vehicles, and
• comply with the following specific route restrictions and any other route restrictions that apply to the route the vehicle takes. (Some road controlling authorities have bylaws which restrict the use of some roads by overdimension vehicles. Contact Transit NZ or the local Council for more information.)

Auckland Harbour Bridge

If your overdimension vehicle is 4.8 metres or higher, and wider than 3.1 metres, contact the Police Communications Centre.

Any load exceeding 3.1 metres wide travelling over the Auckland Harbour Bridge must be accompanied by a Bridge Control Officer.

Any load over 4.8 metres high or 6.2 metres wide won't fit across the bridge, and alternative route arrangements will have to be made.

Auckland motorway

If your overdimension vehicle is wider than 3.1 metres or higher than 4.25 metres, you can't travel on the Auckland motorway (including the northern, north western, and southern motorways). Loads over 4.7 metres high may not fit under bridges on this section of the motorway.

However, loads that exceed 4.7 metres high can travel from the Ramarama Interchange to the south end of Auckland's southern motorway.

Wellington motorway

The maximum height for travelling on the Wellington motorway is 4.8 metres, and the maximum width is 3.7 metres. However, an overdimension vehicle exceeding 3.7 metres wide may travel on the Wellington motorway if it complies with the road controlling authority's conditions.

McKays Crossing/SH1 Paekakariki

Loads or vehicles exceeding 4.6 metres high require permission from the rail operator to cross under the wires.

Lyttelton Tunnel

The maximum height is 4.27 metres, maximum width is 2.6 metres, maximum length for a tractor/semi-trailer combination is 21 metres, maximum front or rear overhang is 2 metres. Overdimension vehicles exceeding the above maximums may travel if the following conditions are met:

• the operator of the overdimension vehicle must obtain permission from the road controlling authority's agent (Tunnel Control)
• the operator of the overdimension vehicle must comply with any piloting or travel time restrictions required by the road controlling authority's agent (Tunnel Control).

Overdimension requirements for excess length

The operator of a vehicle over 25 metres long has to get written permission from the rail service operator if the vehicle is going to travel over a level crossing.

If the overdimension vehicle is transporting a load over 30 metres in length, it has to have a rear steering facility.

If an overdimension vehicle has an operated steering jinker or a pole trailer, the rear overhang is measured between the centre of the rear turntable load support and the rearmost part of the load.

If the vehicle combination includes a load-sharing trailer, the load-sharing trailer does not have to be included in forward-distance calculations if the forward distance is 3.5 metres or less. If the forward distance exceeds 3.5 metres, this distance must be added to the forward distance of the main trailer, less 3.5 metres.

If the vehicle combination includes an operated steering jinker, the forward distance used for determining the overdimension operating requirements is half the distance between the two turntables supporting the load.

Working out the category

The requirements for overdimension vehicles depend on their width, length, forward distance, front overhang and rear overhang. Vehicles over 4.25 metres high are also overdimension, and need to meet the general operating conditions set out earlier.

The graph below shows which category your vehicle and load fall into, based on the width and the forward distance. (Read the factsheet 13 series if you don't know how to calculate forward distance.)

Graph: Determining category, based on width and forward distance

Find the horizontal line on the graph that matches your vehicle's width, and the vertical line that matches your vehicle's forward distance. Where these two lines meet determines your category. (Work out the category for each vehicle in a combination, and follow the requirements for the highest category vehicle.)

Width and forward distance are only two of the five dimensions that determine whether your vehicle or load is overdimension. Your vehicle or load will also fall into Category 1 if:

• the length is more than the maximum allowed for a standard vehicle (including combination vehicles), but not more than 25 metres, or
• the front overhang is more than the maximum allowed for a standard vehicle, but not more than 7 metres, or
• the rear overhang is more than the maximum allowed for a standard vehicle, but not more than 7 metres.

Read the factsheet 13 series if you don't know the maximums allowed for standard vehicles.

Your vehicle or load will fall into Category 2 if:

• the length is more than 25 metres but not more than 35 metres, or
• the front overhang is more than 7 metres but not more than 10 metres, or
• the rear overhang is more than 7 metres but not more than 10 metres.

Any dimension falling into Category 1 (and none in Category 2) puts your vehicle in Category 1. Any dimension falling into Category 2 (and none in Category 3) puts your vehicle in Category 2.

If the vehicle or load is more than 35 metres long, or has a front overhang or rear overhang of more than 10 metres, you are in Category 3 or 4 and need to contact OPIA.

Combinations falling on the upper boundary of Category 1 on the graph are treated as Category 1 loads, and those falling on the upper boundary of Category 2 on the graph are treated as Category 2 loads.

Permits

An overdimension vehicle or load must have a specific permit, unless:

• its width and forward distance combination are within Category 1 or 2 limits, and
• it's no higher than 5 metres, and
• it doesn't have a front overhang or rear overhang greater than 7 metres, and
• it isn't longer overall than 25 metres.

If your vehicle exceeds any of these dimensions, or has a width and forward distance combination that falls within Category 3 or Category 4 areas of the graph above, then you must obtain a specific permit from OPIA (phone their Helpdesk on 0800 OVERSIZE (0800 683 774) or fax 06 953 6313).

If they grant you such a permit, you must carry it in the vehicle when you're travelling and produce it for inspection by an operator of a pilot vehicle or an enforcement officer.

Operating requirements for Category 1 and Category 2 vehicles

The operating requirements set out here are minimum requirements. Regardless of the size of the vehicle, the operator of an overdimension vehicle must ensure the vehicle can safely complete its journey.

In particular, this will require adequate clearance along the route, and the vehicle being able to safely share the road network with other vehicles. The operator must ensure pilot vehicles accompany the vehicle in any areas where it is necessary to provide adequate warning and traffic management to approaching traffic.

Category 1 requirements

These requirements are in addition to the general operating requirements.

Hazard warning markings and signs

Fluorescent yellow flags (at least 400 mm long and 300 mm wide) must be attached to indicate the:

• excess width of vehicle or load at its front and rear
• the front of the load if it has excess front overhang
• the rear of the load if it has excess rear overhang
• the rear of the load if it has excess length.

You may use retro-reflective hazard panels coloured yellow-green with an orange diagonal stripe instead of flags.

If you're travelling during the hours of darkness, the flags must be replaced with retro-reflective yellow-green hazard panels with an orange diagonal stripe.

Hazard panels

The panels must:

• comply with AS/NZ 1906.1.1993 Retroreflective materials and devices for road traffic control purposes, Part 1: Retroreflective materials
• consist of retro-reflective material coloured yellow-green with a 200 mm-wide diagonal orange stripe

• have the illustrated dimensions and orientation

• be frangible.

If the vehicle is over 3.1 metres wide, OVERSIZE signs must be displayed at the front and rear.

You must not display OVERSIZE signs unless required to do so by the Vehicle Dimensions and Mass Rule.

Piloting

If the width of the vehicle or load exceeds 3.1 metres and the vehicle travels during the hours of darkness, the overdimension vehicle must be piloted by at least one Land Transport New Zealand approved Class 2 pilot.

If the width of the vehicle or load exceeds 3.1 metres and the vehicle travels at a speed over 40 km/h, the overdimension vehicle must be piloted by at least one Land Transport New Zealand-approved Class 2 pilot.

Restricted travel times

Category 1 overdimension vehicles must not travel:

• between 0700 hours and 0900 hours, or 1600 hours and 1800 hours, on Monday to Friday inclusive, in any city* area
• between 1000 hours and 1300 hours, or 1600 hours and 1900 hours, on Saturday or Sunday
• at times when there are unusually heavy traffic volumes.

* Note: City is defined as the urban areas of Auckland (between Albany and Drury), Christchurch, Dunedin, Hamilton, Hastings, Invercargill, Napier, Nelson, New Plymouth, Palmerston North, Tauranga, Wanganui, Wellington (including all areas south of McKays Crossing on State Highway 1 and Te Marua on State Highway 2) and Whangarei.

The restricted travel times don't apply to a motor vehicle whose dimensions, although exceeding the maximum dimensions allowed for a standard vehicle, don't project outside the lane in which the vehicle is travelling, and the vehicle (including its load) has been certified (under Land Transport New Zealand approval) as meeting the road space requirements of a maximum size standard vehicle.

Category 2 requirements

These requirements are in addition to the general operating requirements.

Hazard warning panels

Hazard warning panels must be attached to indicate the:

• excess width on each side of an overwidth load or vehicle at its front and rear
• front of a load with excess front overhang
• rear of a load with excess rear overhang
• rear of a load for excess length.

The panels must:

• comply with AS/NZ 1906.1.1993 Retroreflective materials and devices for road traffic control purposes, Part 1: Retroreflective materials
• consist of retro-reflective material coloured yellow-green with a 200mm-wide diagonal orange stripe

• have the illustrated dimensions and orientation

• be frangible.

You must not display hazard warning panels on a Category 2 vehicle unless you're required to by the Vehicle Dimensions and Mass Rule.

If the vehicle is more than 3.1 metres wide, OVERSIZE signs must be displayed at the front and rear.

You must not display OVERSIZE signs unless required to do so by the Vehicle Dimensions and Mass Rule.

Piloting Category 2 vehicles or loads

Most Category 2 vehicles or loads must have at least one Class 2 pilot.

However, if the dimensions of length or height, or the combination of width and forward distance, place the vehicle or load in Category 2 and the rear overhang is between 7 and 10 metres, then there must be at least two Class 2 pilots.

During the hours of darkness a Category 2 vehicle or load must be escorted by at least one Class 1 and one Class 2 pilot.

Restricted travel times

Category 2 overdimension vehicles must not travel:

• between 0700 hours and 0900 hours, or 1600 hours and 1800 hours, on Monday to Friday inclusive, in any city* area
• between 1000 hours and 1300 hours, or 1600 hours and 1900 hours, on Saturday or Sunday
• between 23 December and 3 January inclusive
• on a national holiday, or after 1600 hours on the day preceding a national public holiday
• in any province on its provincial anniversary holiday, or after 1600 hours on the day preceding that anniversary holiday
• at times when there are unusually heavy traffic volumes.

* Note: City is defined as the urban areas of Auckland (between Albany and Drury), Christchurch, Dunedin, Hamilton, Hastings, Invercargill, Napier, Nelson, New Plymouth, Palmerston North, Tauranga, Wanganui, Wellington (including all areas south of McKays Crossing on State Highway 1 and Te Marua on State Highway 2) and Whangarei.

The restricted travel times are relaxed to those of Category 1 if the vehicle (including its load) has been verified (under Land Transport New Zealand approval) as meeting the road performance requirements equivalent to a Category 1 vehicle.

Where you can find out more

• Read Land Transport Rule: Vehicle Dimensions and Mass 2002 (available on our website: www.landtransport.govt.nz and in print from bookshops that sell legislation and some libraries).
• Call the Overdimension Permit Issuing Agency (OPIA) Helpdesk:
  • freephone 0800 OVERSIZE (0800 683 774)
  • fax 06 953 6313.
• Contact Land Transport New Zealand:
  • Email us: info@nzta.govt.nz.
  • Call our Helpdesk: (freephone) 0800 699 000.
  • Write to us: Land Transport New Zealand, PO Box 2840, Wellington.