Skip to main content


Volume 526: debated on Wednesday 30 March 2011

The Department for Transport has today published a consultation on a proposal to allow a 2.05 metre increase in the length of semi-trailers and a maximum overall length for articulated heavy goods vehicles of 18.75 metres. The current maximum permitted length of an articulated heavy goods vehicle is 16.5 metres, and the maximum length of semi-trailer compatible with that overall limit is 13.6 metres. However, the current maximum permitted length for a rigid vehicle/drawbar trailer combination is already 18.75 metres, so the new proposed maximum length for articulated goods vehicles would not mean longer vehicles than are already circulating on Britain’s roads.

The proposal is based on research findings and an impact assessment. It would be a relaxation of the current regulatory requirement on the road haulage industry. The Government accept the research findings which show it could have a significant potential net benefit to road haulage, as well as wider benefits in terms of reductions in congestion, local air pollution, carbon emissions, accidents, noise and infrastructure costs.

In June 2009, following earlier work on longer, heavier vehicles, the Department for Transport commissioned a detailed study into the feasibility and impacts of allowing the use of longer semi-trailers in GB, within the existing weight limit of 44 tonnes gross vehicle weight (GVW). The primary objective was to establish whether the introduction of these high-volume semi-trailers would deliver overall economic, environmental and societal benefits or disbenefits.

The study considered two main possibilities: increasing the length of a semi-trailer by up to 1 metre, to 14.6 metres in total, or increasing it by up to 2.05 metres. The latter option would increase the maximum permitted length of a semi-trailer to 15.65 metres, which would provide the same loading length as an existing rigid truck/drawbar trailer combination.

The study also considered the possibility of increasing the overall maximum permitted length of an articulated lorry to 18.75 metres. This would enable the development and use of tractor units with safer, more aerodynamic, frontal designs in addition to high-volume semi-trailers.

Based on the findings of the study, the Government believe there is a good case for permitting both an increase of up to 2.05 metres in the length of semi-trailers, and an increase in the overall permitted length of articulated vehicles to 18.75 metres. The existing weight limit of 44 tonnes GVW will remain in force. The consultation will enable the Department to develop a better understanding of the practical implications on road users generally of such an increase, and to identify proportionate mitigation measures to minimise the risk of unintended adverse consequences. Depending on the outcome of the consultation, the Government will consider permitting the operation of high-volume semi-trailers on a trial basis pending the introduction of the necessary changes to current regulations. This trial could be helpful to determine whether or not mitigation measures are required.

The consultation will run until 21 June 2011. Copies of the consultation document have been placed in the Library of the House. Further copies are available on the DFT website at Depending on comments received and the Department’s response, amendments may be made to regulations.