Go-ahead for Longer Semi-Trailers

Colin Barnett
May 10, 2023


The use of Longer Semi-Trailers (LSTs) in the UK has been regularised after 11 years of public highway trials. Legislation will be laid in time to approve their use as of 31 May. Use of the trailers, which are 2.05m longer than the current maximum and within an overall combination length of 18.55m, is intended to allow the more efficient transport of high volume, low weight goods. The maximum gross weight however, remains at 44 tonnes. It’s calculated that the trailers could reduce overall journey numbers by 8%, particularly beneficial to sectors such as food distribution and parcels.
The decade-long trials, which have gone largely unnoticed by the general public, have involved 300 operators and 3,000 trailers., during which time an estimated 70,000 tonnes of CO2 emissions have been eliminated. The requirements to employ enhanced operating procedures have seen LSTs involved in some 61% fewer personal injury collisions than conventional trailers. To maintain this momentum in regularised operations, operators will be subject to legal requirements to carry out appropriate route planning and risk assessments, as well as enhanced training for drivers, transport managers and other key staff, loading procedures and record keeping.
On of the companies which have embraced the trials is high street bakery chain Greggs. Its supply chain director, Gavin Kirk, said: “We welcome the introduction of Longer Semi-Trailers (LSTs) into general use. Since 2013, Greggs has been operating LSTs from our National Distribution Centre in Newcastle. We were early adopters of the trial as we saw a significant efficiency benefits from the additional 15% capacity that they afforded us.
“We have converted 20% of our trailer fleet to LSTs, which was the maximum allowable under the trial, and these complement our fleet of double-deck trailers. Our drivers undertook additional training to use these trailers and we have monitored accidents, finding that they are as safe as our standard fleet. Due to the increased capacity, we have reduced our annual km travelled by 540,000, and saved 410 tonnes of carbon per year from LSTs, which supports our wider ESG agenda, The Greggs Pledge.”
For the government, roads minister Richard Holden added: “A strong, resilient supply chain is key to the Government’s efforts to grow the economy. That’s why we’re introducing longer semi-trailers to carry more goods in fewer journeys and ensure our shops, supermarkets and hospitals are always well stocked. These new vehicles will provide an almost £1.4 billion boost to the haulage industry, reduce congestion, lower emissions and enhance the safety of UK roads.”
The trade bodies are broadly in favour, although an RHA statement said: “The Government could however go further by increasing the permitted weight to 48 tonnes. This will be increasingly important when we roll out zero-emission trucks to compensate for the increased weight from batteries.”

About the Author


Colin Barnett

Colin Barnett has been involved in the road transport industry since becoming an apprentice truck mechanic and worked on Commercial Motor for 27 years

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