The other laws of physics apply. Probably Newton's 1st law in this case.
Freeze/thaw/saturation of the exposed supporting soils will be a factor too. Even for a while after they are covered up.
Neighbour foundations - dug and not to agreement - help
- Thread starter Trajan
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Freeze/thaw/saturation of the exposed supporting soils will be a factor too. Even for a while after they are covered up.
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Rubbish - newtons first law is
- a stationary object stays stationary
- a moving object continues to move at the same velocity (at the same speed and in the same direction)
Freeze thaw - what are you on about..to be subject to freeze thaw you would have to have bypassed the Zeroth law of thermodynamics - that when two systems ( ie energy states) are disparate they achieve equilibrium. - so the ground mass behind and below the the exposure will have to cooled to the outside temperature....so the concrete foundation will need to cool the mass behind it and stay at freezing whilst the outside heats rapidly up to an point where the soil fractures by expansion... all the while where the rest of the soil around the building remains completely thermally isolated and not part of the energy system....otherwise that soil mass would heat the small exposed part - you could i suppose induce freeze thaw if you filled the trench with liquid nitrogen...but other than that there is not enough energy disparity to create the conditions.
By the way the last time we had freeze thaw in soils in the UK was during the last glacial period - when the whole ground was chilled.
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Perhaps woody is on about the exposed soil (edge) being vulnerable.
That ground looks awful for building upon.
same law applies - they only thing that suffers from freeze thaw in the uk is rock formations..but that is hydraulic freeze thaw...water penetrates rock and freezes but for that to happen the rock mass must be nearly at zero and night and day temperatures must be below zero. so mountain regions facing north, most scree slopes are from the last glacial period, modern ones as seen in cumbria, the highlands and north wales have taken over 250,000 years to form, most forming from the mini ice age of the mid 1600 to 1700 in the....but in soil this does not happen as soil has less tensile strength than frozen water so just compacts.
The subsoil looks ok, its taken compaction, who cares about the topsoil, that's just infill and looks like a river flood plain rather than spoil.
The subsoil looks ok, its taken compaction, who cares about the topsoil, that's just infill and looks like a river flood plain rather than spoil.
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Reading and quoting things, it's different to knowing and applying them.
In this case the relevance is that an object stays at rest or in motion in a straight line unless acted upon by another force.
Tie that to your previous statement that "Gravity only goes in one direction" and its clear that is not the case in this instance as there are vertical and horizontal forces at play.
All boring I'm sure, but the nett result is that the OPs extension, or the part of it could be at risk of moving downwards and sideways. That's a scientific fact. However the risk of that is unknown, but it's still a risk all the same.
Now on to climate science. Contrary to your belief of freeze thaw, the last time we had a freeze thaw was last week, and the next time will be the next time any exposed soil freezes, expands, then melts and softens. So probably after Christmas now, and we won't need to wait for the Anthropcene.
The op has stated that the trench is no more than 150mm lower than "the base" of their own extension foundation (not clear whether top of concrete or bottom of trench) so everything more than 6 inches above and left of the bottom of the trench is irrelevant backfill - and presumably the ground below that is considered "good ground". If that starts falling out I'd be more concerned about what my entire extension is built on.
A few years ago the council built these parking bays across the road from me, the walls are about 450mm from the foundation at the nearest - when they dug out, the earth was retained by a few scaffold boards and diagonal acrows, for weeks, - and the foundation trench for the walls were considerably deeper than the finished "floor" level. I waited in vain for the houses to fall over but they didn't.
A few years ago the council built these parking bays across the road from me, the walls are about 450mm from the foundation at the nearest - when they dug out, the earth was retained by a few scaffold boards and diagonal acrows, for weeks, - and the foundation trench for the walls were considerably deeper than the finished "floor" level. I waited in vain for the houses to fall over but they didn't.
You normally don't build on topsoil, which is what that looks like from the photo. You normally dig down to clay, rock or sand. It looks like they've gone down a notional 3 feet then given up.
I'm guessing from your photo of the one over the road that yours is downhill from the road. So the soil may have been built up after the house was built, to make a level-ish area around it. Our last house was the same. Despite being 1930s built, I found black turf about 3 feet down behind the back of the house, which was the original soil level. After another foot or two I actually found subsoil, under the original layer of topsoil.
Edit: Confused, thought the post above was the OP. Not the case. Still may be built up land though.
But back on-topic, yours is so solid being full trench fill, they could probably lob a grenade in there and it wouldn't have any effect. They're required to take care, they're not required to follow your rules about exactly how they do it.
I'm guessing from your photo of the one over the road that yours is downhill from the road. So the soil may have been built up after the house was built, to make a level-ish area around it. Our last house was the same. Despite being 1930s built, I found black turf about 3 feet down behind the back of the house, which was the original soil level. After another foot or two I actually found subsoil, under the original layer of topsoil.
Edit: Confused, thought the post above was the OP. Not the case. Still may be built up land though.
But back on-topic, yours is so solid being full trench fill, they could probably lob a grenade in there and it wouldn't have any effect. They're required to take care, they're not required to follow your rules about exactly how they do it.
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I would have got them to do it in two halves. Digging the entire length along a foundation and undermining it by 150mm isn't very high risk but there is a chance of movement. Sooner it is filled in the better.
That block paving need mowing.
Again, you can't dictate that they do this. But if I was them I'd refuse if this was suggested anyway, as it would leave them with a foundation with a bloody great break in the middle. Even if proddling in a bit of rebar to join the halves, they'd have a good chance of ending up with a crack up through the building there. Plus they'd need to pay about a grand extra for the digger for an extra day and an additional load of concrete.
If you build right up to the boundary then you have to accept that your neighbours have every right to dig right up to your foundation. The OP could have avoided this risk by staying further inside the boundary but chose not to.
Neighbours just need give and take.
WE had a similar situation and we were the neighbours putting in new foundations next to existing. 2 sides of a 3 sided trench were dug on one day- had to be by hand as there was no access for digger. Then the next day the trench next to the existing was dug and timed so as soon as the last spade and inspector had looked the cement lorry arrived and was poured.
Sorry yes I meant as the project engineer that's what I'd make them do. The neighbour only has influence under a PWA, although because they've gone deeper they should have had one.
Construction joints in buried mass foundations cast at a similar time don't really matter.
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My advice is don’t fall out with your neighbours over something like this,
I’m sure it will be filled in very soon they may be waiting for delivery of concrete or some other reason… it’s Christmas try and be joyful to them lol
Nothing to worry about imo… if you want to know when the concretes coming just say to them
Is there anything you can help with
Like put sheets down etc … just think when it’s built it will make your house more insulated lol
I’m sure it will be filled in very soon they may be waiting for delivery of concrete or some other reason… it’s Christmas try and be joyful to them lol
Nothing to worry about imo… if you want to know when the concretes coming just say to them
Is there anything you can help with
Like put sheets down etc … just think when it’s built it will make your house more insulated lol
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