Double decking: lost in translation?

According to the latest statistics from the Department for Transport’s (DfT) Continuing Survey of Road Goods Transport, double deck vehicles still only accounted for approximately 2.9% of total product movements in the UK in 2010. This figure actually dropped from a peak of 3.4% in 2008.  

Given the dramatic rise in diesel prices over the same period (up 34% according to the Department of Energy and Climate Change) and the continuing drive for greener, more sustainable transport solutions, it is surprising that double deckers have not seen wider usage in the UK road freight sector.  

Especially so, given the great outcry a couple of years ago over the proposed EC Whole Vehicle Type Approval four-metre height restriction – and the resulting reprieve for the UK.

More prominent in the news at the moment, is the DfT’s extension of licenses for its Longer Vehicle trial, which will give some operators the chance to increase vehicle load volumes by up to 15%, a substantial improvement. But the low uptake of licenses to date (only 550 out of a possible 1,800) suggests there is a very limited market for these vehicles. 

 

On the other hand, apart from for the densest of product loads, double deck trailers offer almost all operators the opportunity to carry between 65% and 100% more product per vehicle. The argument for double decking as a viable green and cost saving solution is summarised clearly by the Freight Transport Association.

It reported: "The advantages of maximising cubic capacity can far exceed any benefits achievable in other areas. The concept is simple: increase payload volume and reduce delivery frequency, hence less mileage, less fuel, less time and, perhaps just as importantly, less CO2 emissions.”

However, despite this apparently simple formula, the real-life complexities and politics of introducing double deck vehicles have undoubtedly slowed their integration. Not least the often-complex relationships between logistics service providers and their customers, between retailers and their suppliers, and between warehouse and transport management. 

The simple equation of volumetric gains is often over-shadowed by the question of cost versus benefit, for example: who pays for the investment in double deck vehicles and associated systems (and despite the potential for rapid ROIs, the cost of investing fresh capital is a potential stumbling block in its own right) versus who gets the benefit?  

Weight sensitivity represents another potential barrier. Powered double deckers are often perceived as the ‘best’ option because they can be loaded and unloaded via dock levellers (albeit with a longer platform and high-bay dock shelter). However, with their onboard hydraulics adding up to four-tonnes to the unladen vehicle weight, these trailers can only offer restricted use for anything other than lightweight loads.

 

Fixed double deck trailers offer a lighter weight alternative, which, for medium density loads, can make all the difference between an operation succeeding, or not. Their simpler design also means that capital outlay per vehicle is roughly 50% that of powered double deckers. On the other hand, rear-loaded fixed double deckers require dedicated loading bays fitted with lifts, which can have a greater knock-on effect on warehouse management.

Transdek still envisages that double decking – in conjunction with developments in fuel and engine technologies, aerodynamics, and IT tracking and routing software – has the potential to make a giant contribution to improving road transport efficiencies for the future. But for this to be fully realised it will need creative and flexible thinking on the part of operators and suppliers – and some of the barriers that exist in the logistics industry will have to come down.

In spite of the obstacles, and the apparent downturn in use, Transdek has seen promising signs in recent years that a growing number of retailers and manufacturers are introducing or expanding double deck trailer fleets.  

Increasingly, we are finding that customers are looking for ways to streamline the effects of double decking on warehouse operations. By designing dock heights at 900mm, for example, operators can run straight onto the bottom bed of standard UK fixed double deck, significantly speeding up loading. For others, the ability to efficiently load any vehicle – single or double deck – off the same bay is a critical element. We are currently working with various companies on different ways to achieve this.  

It was encouraging to read recently that a group of the largest Scottish distillers have collaborated on a project to ship whisky from Elgin down to the Central Belt by rail.  With similar collaboration between retailers and manufacturers on road transport, as has happened with the parcel networks, the volumetric benefits of double decking could be shared by a much wider cross-section of operators.  

The opportunity to make great strides forwards in urban freight delivery efficiencies also exists. The arrival of shorter, low-height, urban double deckers on the market has started to open up new efficiency gains for city-centre and high street deliveries.  In comparison to the traditional urban workhorse, the rigid, a double deck artic can carry up to 200% more product and still allow greater manoeuvrability.  

It may appear naive to picture a future where operators share transport and costs in order to squeeze the maximum efficiencies from the supply chain. But there is no reason why collaboration shouldn’t happen. And with fuel prices still sky high, the incentive to move in this direction is only likely to get stronger.