A mammoth undertaking

The builders have been hard at work on the garden. All of the steel I-beams (all 29 of them!) have been positioned and concreted in place. Since each beam weighs about 1/3 of a ton, and it all had to be done by hand as there is no space for heavy machinery, this was a pretty labour-intensive job. They have been using a little tracked vehicle to take the beams from the drive round to the back of the house, but after that it’s all grunt power. No wonder that the number 2 builder put his back out on Monday and had to go the osteopath to get put back together again!

Here’s a picture of progress to date.

Progress after two weeks of slog

The first row of sleepers is also in situ, carefully positioned to a common level, and concreted into place. That should set firm over the weekend, meaning that next week the rest of the sleepers can simply be slid down the [-sections of the I-beams and they should all line up correctly. Well, I say “simply”, but it’s a four-man operation. Two men at the top, positioning the beam and slotting it into the I-beams, and two men at the bottom, holding it in place with long poles, then gradually lowering it so that it slides down in a controlled manner to rest in the correct place.

If you look carefully, and it’s particularly visible on the upper terrace, you can see that the I-beams aren’t actually resting on the underlying blocks, but are standing slightly away from them by a few inches. This is because the blocks don’t form a completely flat surface, but a distinctly uneven one with bulges. So if the I-beams rested flat against the blocks, it would be impossible to slide the sleepers down without them snagging on the uneven blocks. And that would mean needing to remove lots of the blocks to make a flatter surface – which we want to avoid doing.

The plan therefore is to pour “pea gravel” down the gap between the sleepers and the black membrane. I’m told that pea-gravel acts rather like sand – easy to pour, but then compacts solid. And it will also trap water, improving the drainage. So the underlying soil will be held in place first by the blocks, then by a layer of compacted gravel, then by the I-beam and sleeper combination. I think I can be confident that, once it’s all in place, the garden will be adequately stabilised and won’t be moving anywhere in a hurry!