Maximum sizes for towing

Towing vehicle under 3500kg GVW
Length (excluding the coupling and drawbar)	7.0 metres
Maximum width	2.3 metres
Towing vehicle over 3500kg GVW
Length (excluding the coupling and drawbar)	12 metres if at least 4 wheels
Maximum width	2.55 metres
Length of towing vehicle & trailer combined	18 metres
Maximum overhang of load from rear of trailer	3.05 metres

Further information from: National Trailer and Towing Association (NTTA)
www.ntta.co.uk/law/

Maximum trailer sizes
Type 01: unbraked trailers - max. 750kg gross trailer weight or half the towing vehicle's kerb weight - whichever is less.
Type 02: trailers on overrun brakes - max. 3500kg gross trailer weight.
1982 regulations require that all trailers, including unbraked ones, must be clearly marked with their maximum gross weight in kg. This may be checked at any time by the police at a weighbridge. Since 1 January 1997, all unbraked trailer plates must show the year of manufacture.

Safe weight ratios
For stable and safe towing we would always recommend that you choose the smallest and lightest possible caravan suitable for your intended use. The less the laden weight of the caravan is in relation to the weight of the towing vehicle, the safer and more stable the outfit will be. The Caravan Club, for example, advises that you should aim for a towed load that is no more than 85% of the car's kerb weight for stability and safety. The CC advice is NEVER to tow above 100% of the car's kerbside weight.
N.B. The car manufacturer's specified maximum permissible towload is always the absolute towing limit regardless of any 85% or 100% weight ratio guideline. This is especially important in those cases where the manufacturer's figure is particularly low - in a few cases even below 85%.

Load distribution
Proper load distribution, in general, must be ensured too, with all heavy items in the caravan low down and directly over the axle wherever possible. Correct tyre pressures for car and caravan are absolutely vital.

Noseweight
It is a legal requirement that the noseweight should be 4% of the weight of the trailer or at least 25kg, whichever is the higher.. For safety you should aim for, but not exceed, the lower of the 2 figures specified for caravan and car respectively.

Passengers
It is illegal to carry passengers inside a caravan whilst on the road. It is permitted for pets to travel in the caravan, although this is not recommended safe practice.

Driving Licences
A full (not provisional) driving licence is required to tow a caravan. From 1 January 1997, new category B (generally held as 'normal' car entitlement) vehicles may be coupled with a trailer up to 750kg Maximum Authorised Mass allowing a combined weight of up to 4.25 tonnes MAM OR a trailer (for example a tourer) over 750kg MAM provided the MAM of the trailer does not exceed the unladen weight of the towing vehicle, and the combination does not exceed 3.5 tonnes MAM. This would mean that many drivers who possess only a category B on their licence would be able to tow a caravan provided it was not heavier than their car, and that car and caravan combined, does not weigh more than 3.5 tonnes.
New drivers of outfits over these limits must take a category B + E test.
Further information from: Driver and Vehicle Licencing Agency (DVLA)
www.dvla.gov.uk

Speed
Towed outfits may travel at up to 50 mph on single carriageway roads and up to 60 mph on dual carriageways and motorways. Towed outfits are not permitted in the outside lane of a three or more lane motorway unless other lanes are closed.

Brakes
A caravan with a maximum design laden weight of more than 750kg must be braked with an intertia (overrun) type braking system up to a maximum permissible laden weight of 3500kg.

Road lights
Caravans must have flashing indicators fitted at the back. A buzzer or other means of alerting the driver must be installed to highlight the failure of any of these indicators.
Caravans must have two rear lights conforming to certain size requirements and bearing the appropriate CE mark. Marker lights must be fitted 'as high as practicable' on the side or at the front and rear of caravans over 2.1m wide.

Carrying gas cylinders
Regulations relating to the use of liquid petroleum gas (LPG) in vehicles on the public highway require the gas to be shut off at the cylinder when no appliance is in use. While the vehicle is in motion, no gas appliance should be in use. Special restrictions apply in certain road tunnels, the Channel Tunnel and on ferries. DO check before setting off.

Parking
Do not park your caravan:
 • where it may cause an obstruction
 • at night on a road without lights
 • in street parking bays as some local laws forbid this
 • at a parking meter, as caravans are not permitted
 • unless securely braked or chocked to prevent movement

And finally ....
 • A caravan stored in its owner's garden may be used as a spare bedroom to accommodate non-paying guests. Friends can bring their own caravan and stay within the garden of a house.
 • Caravans must have a rear number plate, matching that of the towing vehicle, and illuminated at night.
 • TVs used in caravans are covered by the owner's domestic TV licence as long the caravan is occupied by someone resident where the TV licence is registered.
 • Caravans do not have to undergo an MOT test.
 • All safety regulations for car tyres apply to caravans. Retread tyres should not be used. Radial and cross-ply tyres must not be mixed on the same axle.

GLOSSARY
GROSS WEIGHT
The total weight of the trailer (or towing vehicle) and load Gross Vehicle Weight (GVW) or Gross Weight Mass (GWM) The total weight of the towing vehicle and its load.
GROSS TRAIN WEIGHT
The maximum allowable combined weight (combined MAM) of the towing vehicle and trailer as set by the towing vehicle manufacturer.
KERBWEIGHT
The weight of the towing vehicle (without payload), including all fluids required for operation, 90% full tank, 68kg driver and 7kg luggage.
MAXIMUM GROSS WEIGHT
The maximum figure set by the manufacturer for the gross weight. This will normally be the technically permissible maximum based on the carrying capacity of the tyres, axles, coupling, suspension and chassis but may have been adjusted downwards for commercial reasons.
MAXIMUM AUTHORISED MASS
As above
MAXIMUM TOWING LIMIT
The most weight a car may tow (specified by the manufacturer).
MTPLM
The maximum weight of the caravan, as stated by the manufacturer (pre-1998 caravans: MGW, or Maximum Gross Weight).
NOSEWEIGHT
The maximum downward force your towball can bear, or your caravan exerts.
MASS IN RUNNING ORDER (MIRO)
The weight of the caravan equipped to the manufacturer's standard specification.
UNLADEN WEIGHT
The weight of the trailer (or towing vehicle) less removable optional equipment and load.
USER PAYLOAD
The user payload comprises all extra items not included in the manufacturer's standard spec. The user payload is the MiRO subtracted from the MTPLM.
VERTICAL STATIC LOAD/NOSE LOAD
The weight imposed on the towball or eye by the trailer coupling.

* NB: For the purposes of determining the gross vehicle weight of the towing vehicle, the noseweight of the caravan is included as part of the car's payload. Consequently, the gross train weight is really the sum of the gross vehicle weight including the noseweight plus the axle weight of the caravan, not its total weight. If the noseweight is not included in the vehicle weight but in the weight of the caravan, there is a danger of overloading the car.