The big drainage sortout

[cookiewales]

whats in the pipe in the hole are you diging in clay or stone :;):

[seanandruby]

don't go any deeper it is too dangerous hole will collapse on on you!!!

[lutonlagerlout]

i dont wish to put out the bonfire but most shovels are 900-1m long and yours is sticking out of the hole by a good 200mm????

did you fill it right to the top shtu?

you have to remember that the soakaway is mainly to take the bulk of the water when it rains hard,it can seep away at its leisure

vast majority of old soakaways we come across are filled with tree roots and water
they are still doing a job though

BTW my local supplier dandys has stopped doing the 4.5m by 4.5m sheets of multitrack non woven fabric
anyone know someone else that does them?
cheers
LLL

[shtu]

Depth - only half of the hole is even 1200mm deep, the other half is about 1000mm. As is, the hole is of a size that I can't dig much further even if I had to.

LLL - are you trying to say I'd exaggerate the size of me hole? Checked it with a tape as I went, just left the shovel in for a bit of scale.

The area I filled is roughly 300x300x200-250mm, the size for doing the test, and that's all that was filled. It's still there this morning too!

Looking at the soil that has come out we seem to have dug down into a clay-ish layer, though there's loads of stones in it too. Bit further up and it looks like normal topsoil to me.

The pipe in the hole is a duct, carries an unused 25mm plastic LPG pipe.

My worry is that by the time we reduce the ground level and fall the pipes to the soakaway, it'll be buried in this distinctly-not-soaking-away layer. Off to mark out levels and see where it works out to.

[shtu]

Ahh, the joys of going and digging a hole...

OK, I've started to reduce the ground levels - the plan was to get them 150mm below finished floor level, but sadly that looks to be impossible.

Some photos,

http://www.flickr.com/photos....2029443

http://www.flickr.com/photos....2029443

http://www.flickr.com/photos....2029443

Now to me that looks like the foundation is those slightly larger stones, which is about 300mm below the floor level. So, I don't think it's wise to lower it much, just take it down to about 150mm below FFL and replace with a base and gravel later to bring it back to in line with the floor level.

http://www.flickr.com/photos....2029443

The "land drain" is, as far as I can tell, a waste of time, as it's buried straight in to the soil,

http://www.flickr.com/photos....2029443

http://www.flickr.com/photos....2029443

So the plan there was to place the land drain in a proper trench as the details on this site show, but move it away from the wall and put it at a lower level.

http://www.flickr.com/photos....2029443

Do you think I'm on the right track?

[lutonlagerlout]

on the right track but be very careful exposing those foundations
TBH i think you need to get someone professional inmlooks dodgy having a land drain that close to the wall
LLL

[shtu]

Thanks LLL, opinion appreciated as always. Have an e-pint on me!

Yeah, since I posted those photos I've cut the excavation depth in half, so now above or at worst level with the foundation stones, they do vary a bit but seem generally level, while the ground slopes steadily upwards from that corner. The other clue that this is the foundation level is slate - started to find odd pieces here and there under the stone.

What I will do for now is reduce the levels (the photos are at the lowest corner) to 100-150mm below FFL, as this can't do any harm - the ground is far too high in some places, 100-200mm above at one point. I will avoid undercutting the foundation stones at all costs.

Once I've got that done I'll see what can be done with the land drain - it can go further away from the building, maybe 2-3ft. Promise I won't dig down yet!

As for "professionals", there have been some had a look, who were of the "yeah, dig a big hole and fill it with gravel, sorted" type - I seemed to have more idea than they did. Anyone got recommendations for someone who covers the Scottish Borders and knows what they are doing (about halfway between Peebles and Edinburgh)?

[rab1]

Haggistini is from scotland, more west i think but if you look at recent posts you`ll find him.

[lutonlagerlout]

thought haggi was/is a taff?
i was talking to an engineer the other day about retaining structures,anyway he said the biggest problem is no weep holes
apparently the higher the water goes the more force it exerts on the wall,even if it is only 4 inches wide but 4 feet high of water that exerts more force than a mile of water deep but say 2 feet high
anyway i am going off tangent here,but if you have foundations exposed you need to get them covered fairly raidly
cheers LLL

[seanandruby]

You can connect your perforated pipe into your solid pipe with a fitting, run to a catchpit before the soakaway to allow cleaning of silt etc. Buy the pre-wrapped perf' pipe it's a lot easier than wrapping it yourself. Mybe you should black jack your lower external walls and maybe bituthene to tank it.

[shtu]

Haggistini. Location : South Wales

The foundations are so shallow (see the sketches on first page) that I'm not sure tanking it would help much. The problem seems to be that people have, over the years, just kept topping up the gravel - most of what I'm digging out is a mix of gravel and soil, then at about 150 down you get to the soil itself.

There's one area that might be a good idea, there's a step between the two halves of the building, so a small area where sloping the ground to cover the foundations on the higher part would leave the ground above FFL of the lower.

The good thing about all this is that the walls are thick (600ish) so should stay stable even with the edge exposed, but I'm not planning on leaving it that way for too long! once we get the rainwater and land drain laid, cover over and build back up to match the FFL.

[rab1]

my bad, for some reason had it in my mind that he was in scotland. :O

[shtu]

Couple of photos for where we got to by 5pm today,

http://www.flickr.com/photos/the_old_smiddy/5090630402/

http://www.flickr.com/photos/the_old_smiddy/5090627766/

This section can be a good bit higher than the first, the floor is about 4-6" higher than the first section, and the foundations seem deeper in relation to the floor on this bit.

In one of the photos you can see how high the soil was in that corner - right up to the damp mark, roughly level with the air brick, so a good 12" above the floor level inside.

[harryp]

Here's some pics of the french drain I installed.

http://www.flickr.com/photos/45979532@N05/

[Stuarty]

Im just outside of Edinburgh if its still of any use mate.