Plenty of 4 metre doubles about and have been for ages.
They are more common than you think. Fixed, hydraulic or the drop down crossmember type for a standard fridge or box trailer. WHEELNUT - pics etc please 
Never mind Malc, found the system I was thinking about 
samro-sa.com/products/traile ⌠-etage.php
Iâve used several of these types in Europe for goods on pallets that could not be double stacked 
If this does come to pass. I donât imagine the law will be on Monday 1st January, all your fleet is obsolete. I imagine that the law will probably say that any vehicles sold after January must conform to the European Height of 4.0m
For a while the 4.2 trailers would be at a premium, just like the lorries with analogue tachographs were in May 2006.
The British are reckoned to be the best engineers in the world, let them prove it, let them get a lightweight semi trailer on the road with a 3m aperture at no more than 4m high.
With good designs it is possible to carry 99 stacked Europallets or 66 on two decks if necessary.
Double deck trailers are nothing new, the livestock industry used them for years, in Europe they kept them under 4m high. Emons are using them over here every day.
When I drove for Transalliance, we ran a lot of mega trailers, 435/50 22.5 tyres, the biggest problem we had was on a loading bank, even with the airbags raised to the max, the trailer was still a foot below the plate, yet in Europe you could drop the suspension, back onto a plate and the forklifts could access the trailer without a problem.
Interesting. Glass Glover Distribution started using these DDs in the mid eighties,carrying 66 cages max.Six lanes and self - loading via a wander lead,freeze/chill any lane you selected,put a bung at the back and fill out with ambient.There was a limit to the weight of each cage though,the pick up beam wouldnât lift it if too heavy,but all in all they were ok once they were errrrrrrrr âfine-tunedâ as they say.
Are there any self-loading trailers like this nowadays?
Right,back to the Old Codgers threadsâŚ
Either Tesco know something we donât about any future EU legislation, or they maybe wasting a lot of money.
Tesco is using Transdek to convert 100 of its top stores to accommodate deliveries from double-deck trailers.
They say the cost saving between a single deck box and a double decker is good for the environment. 45 cages on a standard trailer as opposed to 75 on a decker.
It is using the V2G (vehicle to ground) loading system which is surface-mounted and can be installed and operational within a day. The V2G range is supplied as a pre-clad, pre-tested loadhouse unit, providing a ready-made temperature-controlled and secure environment for goods.
Wheel Nut:
Either Tesco know something we donât about any future EU legislation, or they maybe wasting a lot of money.
Dunno about that Malc, the cost will quickly be recouped anyway and the âgreenâ publicity has a tangible value too. Also, as you rightly said, it wonât be a sudden blanket ban on deckers just a ban on new ones so you would have to factor in the usable life of the trailers before the bays become obsolete. Theyâre probably suitable for 4.2m deckers aswell, saving a fortune in trailer build/maintainence costs by eliminating the need for taillifts. 
New EC proposals sticks to 4m trailer height
Patric Cunnane
Thursday 13 October 2011 10:08The European Commission is refusing to budge from its proposal to limit new-build trailer height to 4m.
At a Brussels meeting today (Thursday 13 October) of the ECâs Technical Committtee on Motor Vehicles (TCMV) the Commission will restate its position that new-build single trailers should be limited to 4m. In a new discussion document the EC suggests that double-deck trailers can run at 4.95m,a slight increase from its previous proposal of 4.88m.
Ahead of this weekâs meeting the Freight Transport Association lobbied the EC at a meeting attended by Keir Fitch, deputy head of the cabinet of Transport Commissioner Siim Kallas and Valentina Superti, head of automotive issues in the cabinet.
âEighty per cent of UK semi-trailers run at 4.2m,â says Chris Yarsley, European affairs manager for the FTA, âThe new EC document allows rigids to go to 4.95m but not trailers. Why?â
The Department for Transport will join the meeting in Brussels to support the industryâs position that the limit should be raised to 4.95m for all trailers. The Federation of Small Businesses will also lend its support at the meeting.
Lets put some new 4.95 rigids on the road instead, that will have some arses twitching a bit
What about double decker buses? Most are well over 4mâŚ
Suppose they could amputate the upper deck, add wheels and hook it on behind, call it a bendy bus
Many motorways are already nose to tail at rush hour, just imagine the M25 with all the extra traffic if all the existing double deck vehicles, buses and trucks, it would need a couple of extra lanes!! (Or another deck 
)
does it not say new build?
Maybe a lot of work for refurbishing ageing DD tralers
Wheel Nut:
Either Tesco know something we donât about any future EU legislation, or they maybe wasting a lot of money.Tesco is using Transdek to convert 100 of its top stores to accommodate deliveries from double-deck trailers.
They say the cost saving between a single deck box and a double decker is good for the environment. 45 cages on a standard trailer as opposed to 75 on a decker.It is using the V2G (vehicle to ground) loading system which is surface-mounted and can be installed and operational within a day. The V2G range is supplied as a pre-clad, pre-tested loadhouse unit, providing a ready-made temperature-controlled and secure environment for goods.
These double deck bays are popping up like no-ones business, tesco westhill, tesco kingsway, tesco crieff road all in the last month.
I canât really see the point in this legislation. If we were in mainland Europe and we had a proportional number of hauliers which go across borders, it would make sense to have a standardised height. Seems as if the EU may not have noticed that we are an island, with higher motorway bridge standard heights, and we have our eastern friends to do most of our importing and exporting who do the work with low trailers.
Itâd make more sense for the UK to be exempted from these particular rules and stick up a few height limit girders on the entrance to the Channel Tunnel and the various different sea ports. Job done!
Wheel Nut:
We have to rethink our engineering and follow the European example, it was they who modernised the transport fleet in Europe, instead of going higher, they went lower. They still manage 100 cube on an an artic and 120+ cube on a roadtrain while still keeping it all under 4 metres high. Most UK container hauliers would not be able to operate in Europe but they are carrying exactly the same containers.
It might work lowering the trailers for normal stuff , but thereâs no chance for a double deck cattle trailer ( or 4 deck sheep) as theyâre already as low as possible !!
Denis F:
Wheel Nut:
We have to rethink our engineering and follow the European example, it was they who modernised the transport fleet in Europe, instead of going higher, they went lower. They still manage 100 cube on an an artic and 120+ cube on a roadtrain while still keeping it all under 4 metres high. Most UK container hauliers would not be able to operate in Europe but they are carrying exactly the same containers.It might work lowering the trailers for normal stuff , but thereâs no chance for a double deck cattle trailer ( or 4 deck sheep) as theyâre already as low as possible !!
Back to open roofs and relying on them to duck then Denis
Seems Asda are confident it aint gonna happen.
Why are we always behined the others ?. I for one will be glad to see the back of these double deck trls i think we should run at 4m or we start run low mega trls. I used a mega truck and trl for 2 yr on eu/uk .
I cant see this happening, But Hope it does for the fact there will certainly be more jobs,
the down side is, Increased costs in almost every industry, the price we pay at the shops etc etc
then the environmental costs implications
But then again, If the industry gets it quashed, then surely the DCPC can be quashed for being a waste of Drivers time, teach me to drive better not teach me to â â â â eggs
You dont lose anything with the cheap Driver Wages in does Days.
Like 50 Years ago when labour was cheap