Special types (STGO) and abnormal loads

What the law says

The Special Types rules permit “abnormal indivisible loads” to be carried which exceed the weight and/or dimensions contained in the Road Vehicles (Construction and Use) Regulations 1986 and Road Vehicles (Authorised Weight) Regulations 1998. A variety of unusual vehicles such an engineering plant or military vehicles, whose design and function prevent compliance with the Construction and Use Regulations, can be used on public roads in certain circumstances.

The rules are contained in s.44 of the Road Traffic Act 1988 and the Motor Vehicles (Authorisation of Special Types) (General) Order of 2003 (“STGO”).

What is an abnormal indivisible load?

An abnormal indivisible load ('AIL') is one which cannot be divided into two or more loads for carriage on roads without undue expense or risk of damage and which:

  • owing to its dimensions can only be carried by a heavy motor car or trailer or a combination of these which does not comply in all respects with Construction and Use Regulations; or
  • owing to its weight can only be carried by a heavy motor car or trailer (or a combination of both) with a total laden weight exceeding 44,000kg and which does not comply in all respects with Construction and Use Regulations.

STGO operations

There are three weight categories for STGO operations:-

Category Maximum gross vehicle weight (kg) Maximum category gross weight
1 - 50,000kg
2 D x 7,500 80,000kg
3 D x 12,500 150,000kg

Where D is the distance (in metres) between:

  • the foremost axle and the rearmost axle of the vehicle carrying the load; or
  • in the case of an articulated vehicle, the kingpin and the rearmost axle on the semi-trailer; or
  • in the case of any other description of combination, the foremost axle and the rearmost axle of the group comprising of all those vehicles in the combination that are carrying a load.


ESDAL stands for 'Electronic Service Delivery for Abnormal Loads'. Legislation requires that vehicles and load movements that exceed the standard dimensions need to be pre-notified to Police, Highways Agency and bridge authorities.

Using ESDAL’s innovative mapping system, hauliers can identify the route they need to take, and get full details of all the organisations they will need to notify before making the movement. Hauliers can also perform an appraisal of the route for an indication of the suitability of their vehicle.

ESDAL does not require any specialist software. It only requires a PC with internet access.

Notification procedures

The minimum notification time for a Special Types movement varies according to STGO category. Notification may be required by the Highways England, bridge authorities and police. A form of notice is downloadable from the DfT website.

For loads of widths of 5.0 to 6.1m operators need to complete form VR1.

The maximum permitted limits for STGO operations are 6.1m width, 30m length and 150,00kg weight. Outside these limits a Vehicle Special Order is required. Approval is not automatic and is at the discretion of the Highways England. Use form BE16.

Police notification: This must be given if

  • The vehicle width exceeds 3m; or
  • The vehicle or load length exceeds 18.75m (discounting the length of the towing vehicle on an articulated vehicle); or
  • The total length of vehicle and trailer (including projections) exceeds 25.9m; or
  • The load projects more than 3.05m to the front or rear; or
  • The gross weight is over 80,000kg.


The notice must be in a form acceptable to the recipient and should be agreed by both parties.

The notice must contain:

  • a list of all police forces to which notice is being sent;
  • details of the user of the vehicle or vehicle-combination, stating:address, telephone number, fax number, email address (if any), user's licence number, user's reference number;
  • details of the intended use of the vehicle or vehicle-combination, stating:point of departure, point of destination, time, date and route of journey, particulars of any load (including description and profile of load);
  • details of the vehicle or vehicle-combination used, stating:registration number of any motor vehicle, type of vehicle or vehicles, overall length of the vehicle or vehicle-combination (including length of any front and rear projection), overall length of each single rigid unit included in a Part 2 vehicle-combination (including length of any front and rear projection),overall width (including width of any lateral projection), maximum height, gross weight or gross train weight, number of wheels per axle, all axle weights, all axle spacing.

Marking and attendants

AIL’s projecting forwards or rearwards may have to be marked and special types vehicles must carry a statutory attendant in certain cases as shown in the table:

Any maximum plated motor vehicle weight over:

Vehicle dimensions or weight limit of application Police notice Road and bridge notice Working days notice Attendance and markers
Any maximum plated axle weight over 10,000kg or 11,500kg for drive axle Yes Yes
Any maximum plated weight over 80,000kg Yes, 2 days Yes, 5 days2 days or 5 days
Width of load or vehicle over 3m Yes 2 days
Width of load or vehicle over 3.5m Yes 2 days Yes
Width of load or vehicle over 4.3m or 5m if Abnormal Indivisible Load Vehicle (needs formal Department for Transport VR1 Order) Yes Notice as required by individual vehicle registration movement order 5 days from receipt of formal order
Width of any lateral projection over 30.5mm either side of vehicle body Yes 2 days Markers only required
Length of vehicle or load over 18.75m (includes articulated vehicles) Yes 2 days Yes
Length of a combination of vehicles carrying the load over 25.9m Yes 2 days Yes

Updated by Lucy Wood & Anton Balkitis
Freephone: 0800 046 3066