Let's follow the journey of aggregate being used to prepare the floor area.
First two bags are hoisted high into the sky, 
taking care not to bring down the broadband fibre optic cable!
Over the top of the roof it goes...

The arm of the crane does not remain ridged, but is constructed so it bends slightly with the weight it is transporting.  The workmen in the quadrangle look skyward, waiting for the bags of aggregate to arrive.

As the bags arrive in the quadrangle the man controlling the crane cannot see the bags so he has to be guided by a radio link by a workman in the quadrangle.  The bags of aggregate are moved to exactly the area where they will be needed.

The bottom of the bags are then slit with a knife to allow the aggregate 
to pour over the ground.  It can then be smoothed out by hand.

In the week that followed a layer of sand in pressed into place over the aggregate.  Then another trench dug down the middle for a beam to be placed later.