More destruction
As agreed with the architect, we demolished the gable-end wall with no foundations at one end. It faces north, overlooking our driveway and the shared access track.
We put two bays of scaffolding, 2 tiers high, across the front, giving us a top platform just the right height to remove the top-most capping stones. I put boards at convenient levels to lug all but the largest stones down. I used the chain hoist and webbing straps for the really big ones. Smaller bits of stone I chucked off the side and periodically barrowed to a pile the other side of our driveway.
At the top of the wall, I made slow progress because the chain hoist was very slow to use, however the mortar broke apart easily – our pry-bar was more than equal to the job. As I worked down, the hoisting got quicker, but the mortar was progressively harder. I stopped once we were below wallhead height, I would have needed to use a breaker to carry on down and Ric could finish the job with the digger. I worked the wall back towards the west corner, allowing room for the garage door and quoin stones. I did clear the unsupported stonework on the east side right down to ground. It was overhanging part of our drains and at several points I used a length of rope to hold stones in place to stop it all collapsing.
The soakaway: Our surface water soakaway needs to hold 16 cubic meters of rubble, to give around 4 cubic metres of free space. This is what the standard calculation says we need, to cope with our 200+ square metres of roof plus a steady flow from our diverted field drains. Our high water table meant it would be a 4m x 4m x 1.3m deep hole in the ground near our southern boundary, allowing for 30cm cover.
The hole was scarily large, we cleared suitable lumps of ready broken concrete from across the site but ran out, with what looked like a puny pile in one corner of the hole. We moved over to our big concrete pile and scavenged all the bits of easily-breakable hardstanding that George had piled up there. I did duty with the sledge hammer to break them to size. We could have used the hundreds of tonnes of large blocks of concrete, but it was much harder and more thankless work. We started with wheelbarrows to get the rubble to the soakaway but were relieved to get hold of the 1-tonne mini dumper truck – life immediately became a little more attractive. The hole was rather more than half-filled before we ran out of easy stuff to break. Ric took pity on us and lifted fresh hardstanding in the courtyard, which lasted us almost to the finish. We foraged further onto the concrete pile for the last three dumper-loads.
It was a miserable job, over four working days – with lighter work to break it up. Ric had worked in parallel on the drain to the soakaway and ran brown pipe into the middle of the rubble, 30cm below the final level. We spent a while getting a level surface to the rubble and it was done.
It was remarkably effective. Being somewhat jagged, the broken concrete locked together with plenty of open space, yet was firm enough to drive the loaded dumper onto. We ordered weed membrane to go on top, Ric will finish it off with subsoil and then topsoil after we have headed south.
Surface drains ‘getting there’: Ric dug the drain trench back up the plot from the soakaway, to the junction he had buried last year. He put an inspection chamber in, not far from the soakaway, so that we can monitor how the whole thing performs. He broke two holes into the big concrete tank, to run brown pipe downstream and upstream. We used pea gravel to lay and level the pipes, topped them with gravel and filled the trenches. A neat operation that took around a day, plus time to cement the drain pipes into the tank.