Groundworks Week 2 - mission - excavate trenches for the foundations and "pour" concrete.
The site was levelled and marked out with pegs / strings at the end of the previous week. Tim on the digger carefully excavated each trench to the required depth, directed by James using a laser level.
Carving out trenches like this.
The water seeped into the trenches from the clay sub soil. This is an issue for foundations - concrete is weakened if it is poured into water-filled trenches.
We were also worried about tree roots. We are building in our garden and there were stumps of leylandii, ash, sycamore and willow trees. Roots can weaken the sub-soil by extracting water while the tree is alive and even after felling, the ground can remain unstable.
Progress was rapid and the weather was kind to us.
These are the strip foundations looking through the garage and along the N-facing wall of the new house.
In fact, we were very lucky not to encounter any major tree roots - the Building Inspector might have insisted that we excavate deeper trenches, pour more concrete, spend more money etc.
Water levels rose as we worked further down the garden ..
End of day 1 - most trenches excavated and passed by the Building Inspector.
Another clay mountain taken away by 20-tonne lorry.
In total this week, we removed 9 lorries full, just from the trenches and oversite.
Tree roots were no match for Tim on the digger.
Wednesday was Concrete Day.
This enormous concrete pump arrived very early in the morning.
It was so tall that it would not fit under the telephone wire. These 4 men could not figure out how to push up the (round) wire with a (round) length of conduit.
So Sarah had to intervene, inventing a solution with a garden fork in the end of the pipe. (None of the men admitted she was right ..)
The first of 9 cement lorries arrived promptly, bringing concrete from Ketteringham near Norwich.
The concrete was mixed en route and water topped up on arrival on site.
The concrete was lifted out of the mixer with an Archimedes Screw and dropped into a hopper on the back of the pump lorry.
The telescopic arm of the pump was then extended out over the site to deliver the concrete into the trenches.
Concrete was simply dropped into the trenches and lightly rammed down by hand.
The pump was controlled remotely (chatty man in orange trousers).
And the groundwater was pushed downhill by the spreading concrete and pumped out of the lowest point - clever.
The process was managed very efficiently by James, with concrete lorries arriving just in time.
Amazingly, the trenches were filled by late morning and (on another fine day), the concrete started to harden.
Next day, the site was stripped level by removing the soil from between the trenches.
We retained this soil to use in the garden (there's a LOT of it).
We could now see clearly the shape of the new house on the ground.
The final challenge was to remove the stump of a large ash tree - this was almost too much for Tim and his digger, but machine prevailed.
After filling and rolling the ruts in the drive that had been made by the lorries, the groundworkers levelled the rest of the site, loaded up their digger and dumper and departed.
10 days to construct a 50 m drive and the foundations of the new house - we are massively impressed.
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