It’s worth digging a few test holes further out in case it’s just backfilled with sand around the foundations and there is better depth of soil elsewhere. That’s bad enough, but what’s more worrying is that I can’t see a damp-proof course in the brickwork, you can already see damp seeping into the wall and your mortar is going green. I would get a surveyor to look at that pronto.
To the left of the post is the garage, (you can see where the damp proof couse is 2 bricks up)
To the right of the post is just a retaining wall as there garden level is 1 meter higher than my garden, this is why this wall is more damp.
I do think that retaining walls with soil behind should not be allowing mosture to penatrate as it will affect its long term stabability, but I am no expert.
I will dig mote holes to see how far the sand gos along that wall, as I know the bottom edge of the garden is just clay subsoil.
Ok so I'm looking at the pictures and it looks like the houses are being built on a very slopey site, is this right ? House foundations are 150wider than the brick work though if it is built on piles with a ring beam (very common these days) then there isn't any extra width to the beam so nothing protrudes beyond the bricks. Equally if the site is so unlevel the builders can import soil/sand/aggregate to level the soil around individual house's. We have sites around here where ground levels are being raised over 1mt to level the ground. As far as build quality goes foundations are possibly the hardest area to take short cuts on as building control are absolutely red hot on it. Undoubtedly other areas are allowed to slip but most often these are areas not covered by building control and are simply down to pure quality control.
While not ideal, people garden on subsoil which is almost pure sand, so I would have thought digging out and laying about 300-450mm depth of topsoil in your beds would be fine. Choose species suitable for a sandy soil when planting. Raised beds would give you even more leeway. The lawn can probably get away with the topsoil depth as it currently is.
You don't really need to dig out the whole garden to 1m depth!
Get the drainage sorted out though. Your French drain will have to have an outlet somewhere, or it won't help at all. In fact if your subsoil is all sand, it should be pretty free draining by itself - the problem is it hasn't got anywhere to drain to, by the look of it. Looks like there's a retaining wall at the end - does it have weepholes on the other side? If so you might need to clear them and dig a stone filled trench alongside, lined with filter fabric to stop it clogging.
"What is hateful to you, do not do to your neighbour".
While not ideal, people garden on subsoil which is almost pure sand, so I would have thought digging out and laying about 300-450mm depth of topsoil in your beds would be fine. Choose species suitable for a sandy soil when planting. Raised beds would give you even more leeway. The lawn can probably get away with the topsoil depth as it currently is.
You don't really need to dig out the whole garden to 1m depth!
Get the drainage sorted out though. Your French drain will have to have an outlet somewhere, or it won't help at all. In fact if your subsoil is all sand, it should be pretty free draining by itself - the problem is it hasn't got anywhere to drain to, by the look of it. Looks like there's a retaining wall at the end - does it have weepholes on the other side? If so you might need to clear them and dig a stone filled trench alongside, lined with filter fabric to stop it clogging.
Thanks for the advice. Yes builder did say they would tap it in to existing down pipes from the garages at the back. The wall dose have 2 weep hols but Iv not seen any water come from them so may need a good poker up there 😆
I have subsoil which is almost pure sand plus stones (including large ones). That drill thing would never work in my soil. I think your hole is too close to the house for you to be sure it is the same in the rest of the garden but even if it is, it shouldn't be a major problem, just dig in some soil amendments and then continue to mulch every year. It will be perfectly fine for most plants.
I don’t think it’s the hole garden just along that wall. I suspect it’s where the scaffolding was when they build that garage and they just filled amd leveled it off with the sand. I know there is no sand under the middle of the lawn and the bottom of the garden. But I suspect there is sand on the right hand side as well along my garage on the right.
To the right of the post is just a retaining wall as there garden level is 1 meter higher than my garden, this is why this wall is more damp.
I do think that retaining walls with soil behind should not be allowing mosture to penatrate as it will affect its long term stabability, but I am no expert.
Retaining walls should always be built to prevent any water build-up behind them. Water can add a significant pressure to the wall which is the real threat to stability. Weep holes are a secondary precaution though and a land drain should be taking the majority of the water to a suitable disposal route (IE to the same place the water from your roof goes).
Your sand looks to be the backfill from a foundation trench. The developer should still have allowed 30cm of top soil above any fill though. Most don't seem to bother sadly.
If you can keep your head, while those around you are losing theirs, you may not have grasped the seriousness of the situation.
It's winter and even with an amazing drain system gardens will be quite wet not far from the surface. Rainwater should be directed to soak aways and not into drains (if all rainwater went into a sewerage system most areas would flood in no time at all), at this time of year soak aways will be pretty full so drainage can be slow. Land drainage is definitely a forgotten part of estate house building, we have 2 smaller estates near us built late 80s early 90s which both have large ponds built in to allow for inflow of heavy run off that then seeps away through a large herringbone drainage system it works really well. The same builder had to stop doing this as he couldn't fullfil the minimum density of homes for planning permission with the pond taking such a large, short sighted planning rules
The garden in our second home was on a south facing sand dune. Apart from it being very well drained and extremely hungry (tons of manure added every year which soon disappeared in the subsoil), everything grew very well. I went down over 9 feet looking for the sewer (long story) never found it, but it was sand all the way down. Actually used the sand to make the concrete for the extension which I built.
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You don't really need to dig out the whole garden to 1m depth!
Get the drainage sorted out though. Your French drain will have to have an outlet somewhere, or it won't help at all. In fact if your subsoil is all sand, it should be pretty free draining by itself - the problem is it hasn't got anywhere to drain to, by the look of it. Looks like there's a retaining wall at the end - does it have weepholes on the other side? If so you might need to clear them and dig a stone filled trench alongside, lined with filter fabric to stop it clogging.
I think your hole is too close to the house for you to be sure it is the same in the rest of the garden but even if it is, it shouldn't be a major problem, just dig in some soil amendments and then continue to mulch every year. It will be perfectly fine for most plants.