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What finer way could a blazing hot sunny day be spent than barrowing and shovelling a tonne of concrete? ????

This Sunday I started the day by cutting some of the outer floor timbers to length and digging the previously-mentioned radiator brackets out of my pile of scrap metal to use to fix the timbers to the pads. Then came the hard part: shovelling the ingredients for the concrete into the mixer, wheelbarrowing it to the right place and shovelling it out again. I certainly won’t complain about the weather because it’s such a pleasure to be able to spend so much time outdoors, but by the time I finished my clothes were totally sodden with sweat and I was almost on my knees.

Very pleased to have got it all done though. Here’s how it looks now:

Not entirely sure where I go from here. I think I need to get all the concrete work done, but that means knowing exactly how my piers are going to work out so I can sink the bolts into the concrete in the correct places. I might have to finish the pier design and then talk to the chap who is going to make them.

Having decided that I can wrap the timber in DPC material to protect it from damp, this Saturday afternoon I lowered the shuttering for the two concrete blocks that I’d already put in place so that the highest one will have its top at ground level. After that I dug out the space for the two other corners, which didn’t require a huge amount of digging as I found rock about four inches down. In fact there’s so much rock close to the surface that I gave up trying to get the pads square with each other. As long as they’re bigger than the obsy base, that will have to do. The shuttering for the lowest pad still looks huge as the ground level there is over two feet lower than at the highest one. I may well re-use that shuttering for making the pier foundations.

The plan for tomorrow is to get the outer timbers of the floor made up and then get the concrete poured for these four pads. The floor timbers will allow me to place the strapping (which may actually turn out to be some old radiator wall brackets) to tie the frame down accurately.

I have some stones and broken up concrete blocks that I’ll also throw into the pads as I need to get rid of them and it will reduce the amount of concrete I need to make. I do need to be careful that the shuttering doesn’t “float off” given the weight of the concrete though. I might have to rest a few more blocks on top just to stabilise things.

Though I’m not 100% confident in my welding skills, I’m coming round to the idea of making the frame for the rolling roof section from a square section steel tube. I think in the end it will be lighter, less flexible and require a less complex design. It should also mean that I can have a ridged roof rather than a flat roof which I find more aesthetically pleasing. I’ve roughed something out in Sketchup, though it may change.

For holding the roof closed (so it won’t lift off) I’m tempted to use something like this:

which is actually a pin used to mount tractor implements on a three-point linkage. It could pass through a plate with a hole fixed to the walls so the roof won’t lift. When it is to be closed up for an extended period I could even use the usual spring-loaded retaining pin through the hole in the end:

Plenty more to think about before I get that far though.

Once I’d mowed the grass in the planned area I wasn’t entirely happy about the steepness of the slope. The floor deck will be built off six concrete pads and the pad at the bottom of the slope would have been over 600mm high. To reduce the height a little I decided to move everything about another metre away from the house.

That done, this afternoon I started digging out the space for the first two pads. Having the right tool for the job should save a lot of time.

Sadly I was a little slowed down because I managed to jump one of the tracks off the digger. I knew I needed to check it but I forgot and paid the price. Fortunately it wasn’t too hard to lever back on with a long steel bar whilst holding that side of the digger in the air with the bucket and running the track forward (not recommended practice, I imagine, but probably happens far more often than anyone will admit to.

I got the shuttering in for the first pad late this afternoon, recycling the base of a trailer in the process, though I have to admit I’m not entirely sure how reliable the ply is any more. It may not look it, but the spirit level does actually say it’s level in both directions.

I managed to get the shuttering in for the pad on the left (also recycled, this time from a shelving unit that has seen better days) as it was getting dark. Need to check the levels again in proper daylight.

I’d really like these two pads to be a bit lower, but the top of the one in the photo above is only 150mm above ground level and I’m not sure I want to go closer to the ground than that with the timber. Perhaps 100mm clearance would be sufficient. I shall ponder on it before I start the next one.