The importance of ‘L’

Over a couple of months, we kept revisiting the design ideas drawn up by E3 Design. One of the youngest members of the team, Kev Crulley, had an idea that was basically two ‘L’ shaped ‘halves’ attached together to form an oblong box shape.

As it’s a very simple shape, we can use a very basic and cheap method of manufacture called extrusion.

It’s the same manufacturing technique used to make things such as drainpipes and picture framing moulding. It can be cut to any length and you can stack the oblong ‘boxes’ on top of each other to build a wall.


… Apart from a few obvious problems.

  1. How do you join two ‘boxes’ together side by side?
  2. How do you go around corners?
  3. If it’s a flood defence, how do you fill the box so that the wall doesn’t float away?

All the solutions, such as connectors and pre-filling the boxes, weren’t really appealing.

So, again, it was back to the drawing board…

Bonnie Prince Charlie and his place in 21st Century construction

A few months passed and nothing was happening… it’s fair to say the idea had been parked.

Then the eureka moment came one Sunday morning…

For two weeks in a row I kept waking up having dreamt of the Battle of Culloden. For those not of a historical disposition that was where in 1746, the English defeated the Scottish uprising led by the grandson of the deposed King James II, namely ‘Bonnie’ Prince Charlie.

  • “What’s that got to do with walls?” I hear you ask.

Absolutely nothing, apart from the fact that to defeat the Scots, the English commander, the Duke of Cumberland, changed one crucial tactic.

He had his troops line up in the traditional ‘thin red line’, his men armed with only single shot muskets with a bayonet attached to face the formidable ‘Highland Charge’ of claymores and targe (shield). But as the Scots clashed with the English rather than each English soldier engaged the man directly facing them, instead he had been drilled to thrust the bayonet at the Highlander diagonally right of his direct assailant.


Because the sword arm of the adjacent Scot was raised to attack, most men being right-handed, the right side of his body was exposed. The targe in his left hand was ready to defend an attack from the English soldier directly in front of him, but the strike came from the side to the exposed right side of his body. The result was total carnage in the Scottish ranks and an English victory.

  • Yes, yes… all very interesting but it still has nothing to do with building a wall.

Well, it does if you think of the English battle technique as ‘overlapping’.

Think of the two halves of the wall as the opposing English and Scots and overlap the pieces – then you never have a joint only a ½ joint.

All you have to do then is cut a piece to ‘square up’ the wall!!

Whilst we didn’t fully understand it at the time, we’d solved one of the biggest problems in building – horizontal integration.