We finished the ringbeam and then Dawie and his unsupervised crew set about replacing the ribs and blocks, installing the props and shutterboard. They were unable to make much progress and only when I took a video of their unproductive time, did I manage to convince Dawie that perhaps he should begin supervising. There was mention of lawyers, court and a few other incentives to convince him of the merits of supervising which may have helped him in his decision. Of course all of the delays were due to the fact that it was an unconventional roof, but we all knew this beforehand. Being unprepared and without a plan did not help matters, but eventually with his supervision there seemed to be a much improved output of work.
The benefits of having done the ringbeam first were significant. The surface was finished at the correct angle which made setting the ribs up very easy. It was helped by the fact that the reinforcing was fixed with the correct spacing permitting the beams to be easily installed without much hassle. The beams, which were two steel lip channels 11m in length were first welded together by Poen our retired millwright. This gave them added rigidity especially as they were straddling a large span. Since the beams were steel, we were able to weld the beams to the reinforcing which prevented them from moving when they were finally correctly positioned. This gave us a significant amount of peace of mind especially as without the concrete the roof is in fact quite light and if the wind were to get under the roof, it could easily move or dislodge it. Another benefit of having done it this way was the fact that the 600mm upstand beam was now seen as a 110mm downstand section with 340mm buried in the roof leaving around a 150mm upstand section. This would be a lot less unsightly and would permit us to cover the whole roof with planted material rather than just the section between the beams.
The process of placing the beams and blocks was quite simple and easy. One problem we encountered was that the engineer's drawing did not take into account the actual block dimension which meant that we were two beams short. This was a frustration but in his defense, he was given the incorrect dimensions by the supplier. However it meant that we had to get the additional beams welded and additional reinforcing bent, supplied and fixed. Of course, one thing that I've discovered is that when you're not paying for the items nor working to a budget, it's very easy to glibly call for more materials rather than calling for more thought.
I don't know how many props we used in the end but there were many. With the blocks on and the props in place, the site looked 'busy'. The electrician finally came in and he was very efficient in placing his conduits. These we double checked and hopefully we have not missed any out. However we are using prefabricated internal walls which are 50mm thick. This meant that the conduit pipes had to be accurately placed in position and Johan took a couple of days marking out the walls on the floor using cement. Using a plumb-bob we then checked the alignment of every conduit. 
For the electrician using polystyrene blocks was a first. One benefit is that he can move his conduit within the area of the block quite easily after the concrete has been cast so he has some room for error. He can also easily push his conduit through the block and in many cases did not need to install a slab box. However, where the chandeliers were due to be hung, he was worried about the strength of the block to hold up the weight. In these area's he inserted a piece of wood to which he will attach the fitting. Like all the tradesmen, he brought around some of his mates to show them this unique house, which now is not just the unique walls but also the unique roof.
Our internal walls will be supplied by Space-Frame, a Gauteng based company. These are welded wire frames with a layer of insulating material that are rapidly erected by splicing the panels together and then rough plastering them with a 10mm layer of concrete on each side. 
Later it is skimmed to whatever finish you require. To attach them to the floor, a small foundation is cast with Y8 reinforcing to which the wire frame is attached. We did the same through the roof which means that both the top and the bottom of the wall will be firmly anchored in place. We are hoping to install all the internal walls in 14 days which should be possible.
The unconventional part of the roof was the shuttering required on the edges of the roof. Normally the builder bricks up a small wall that contains the (horizontal) slab, but in this case the roof has quite a large overhang and the overhang itself and the edges needed to be shuttered. The issue was to support the shutterboard on the edge. If it moved, then the edge of the wall would kick and we would not have a straight edge finish. Then we had the issues of the two upstand beams that should have been shuttered to get the square finish. Despite Dawie's best intentions and promises to be ready by Thursday 4 Feb, it was apparent that there was still a lot to do. The concrete was delayed to the Monday, then the Tuesday and finally to Thursday 11 Feb. On the morning of the 11th, he was still busy with the upstand beams and by the time the concrete arrived about 25% of this work had been done. I realised that this was a disaster waiting to happen and decided that we should flow the concrete over the beam so it would look like a traffic calming bump rather than a beam. The engineer was fine with this and in the end, this is what we did. Since it would be below the soil, whatever the finish, it would not be visible so for all intents and purposes was irrelevant.
Eventually we were ready or rather the day had arrived for the concrete and any outstanding issues remained outstanding. The one major unknown was how the concrete would behave on a pitched roof. We had been told that it would run off the bottom by a variety of professionals. So we had ordered the stiffest concrete that could be pumped through a concrete pump. As it was around 30+MPa and had a serious waterproofing additive and fibre reinforcing we knew that it would want to set fairly quickly. The trucks arrived on time as did the concrete pump and we set to work.
It was surprisingly fast and the concrete pump with its flexible elephant trunk hose emptied the trucks in minutes. The speed and mass of the pumped concrete began displacing the polystyrene blocks which created gaps in the roof through which the concrete poured. There were moments of joy followed by shouts when the concrete was flooding onto the floor of the house. Quite quickly it became apparent that we needed extra hands and Johan's entire team who were busy with the shed were summonsed onto the roof. We had teams holding the blocks in place whilst others were spreading the mix. We had a group retrieving the fallen concrete and this was returned to the roof. It was a mix of mayhem and order, swinging from one extreme to the other. However in the end we made good progress. What was evident was the fact that the concrete did not run off the roof. It behaved exceptionally well and when vibrated filled the cavities like good concrete should. At least it did not run like a scalded cat.
Dawie had one vibrator working and finally turned on the second unit. This promptly ran out of petrol (no petrol) and he rushed off to buy some more. We used more concrete than we had calculated and there was a big break between the last trucks of concrete that had the pump controller in a state of concern about the concrete setting in his pipes. Eventually our extra concrete arrived and we managed to fill the last cavity with a bit to spare (which we used for the worm farm).
After realising that we would get the roof up in one piece, I was keen to get the finishing done properly. Of particular importance was to get the fall to the drainage pipes correct. These pipes would be collecting our rainwater and it essential that the roof drains thoroughly to these points. While I was insisting on this, the concrete power float was started up in an attempt to get a smooth finish to the roof. The concrete was hardening quite fast. If done properly, this would result in a varnished finish that would ensure any water would easily and rapidly run off the roof. This began in a promising fashion and it looked like we might actually successfully finish the job. 
From bitter experience, I've seen a poorly floated floor and it would have been better to hand finish the floor rather than power float it. So I was keen to ensure that this would be done properly. It did not help when one of the floats did not work and when the hire shop was called to provide another one, we were told that he would supply one the next day!! (Noun!) While the float was busy, a crew set about finishing off the rounded upstand beam by hand and creating a perfect fall to the drainage points. There was hope yet.
So how did it end up? mmm... the water certainly runs down the gradient. It doesn't leak and considering the cost of the roof this should not come as a surprise. The fall to the drainage holes is uneven (another UN), the floated finish according to the Urban online Dictionary is as rough as a badger's arse and our solution is now to smooth it out with a slurry! Another layer of cost:) In the meantime, we are curing it by keeping it flooded by irrigating it and we're now into day four. So now it's as rough as a wet badger's arse which is no smoother than a dry one if it's made out of 30MPa concrete. Apparently the slurry might come tomorrow or it might not. Dawie's car broke down again so who knows when it will happen? But until it does not look like a badgers arse - wet or dry, I shall continue badgering.And on the upside, at least I have a roof that appears waterproof despite it being unconventional, made out of CO2 unfriendly concrete that will forever remind me of a badger. And I'm sure there's a noun in there somewhere
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