Deejay_2

Just a quick update as not much has happened. Still waiting for confirmation of "commencement" from BCO. Have just paid diggerman - £560 which I think is reasonable for 2 trial holes, one 8 m trench 1.2 m deep, and exposing massive roots of conifer. Two visits in all. Grinder coming to deal with conifer stump on 30 June so will post photos.

The different BCO called today. He said the trench is fine. I asked about part back filling the trench but he said no as that would mean we had not "commenced" the work, which I know is right. I am just concerned about the nearness of the wall to an open trench. I am now in a quandry as to what to do. He said get the concrete in but we wanted this to be as least expensive as possible in case I die in the near future and the proposal is abandoned and also due to our current financial situation (plus not 100% certain of diggerman's setting abilities - will get a professional to set out the whole site before any further excavation is done). So Should we purchase some OSB boards and cover the trench, plus cover the OSB with heavy duty plastic sheeting, leaving the soil dug out piled up at the side of the trench. Wait to receive the commencement email and then wait a further couple of weeks before asking the diggerman to come back and refill the trench. I'm not dishonest by nature and if they found out and retracted the commencement proof, we'd have to dig it all out again and be back where we are now. Is there any reason they would find out. No one else can see the trench. I would hope the diggerman wouldn't blab but he is a bit of a gossip. Put in the concrete which we really don't want to do. Any opinions on what individuals would do in my situation would be much appreciated.

OK - the stump man has been out - he has asked that we dig about a 6 ft square 10" deep area in front of the stump to form a sort of ramp for him to get his machine in. If we do this he will be able to get most of the stump out I think. He is busy for a few weeks so it won't be immediate - £180 which I think is reasonable. We have a different BCO coming out tomorrow to inspect the trench - I'm going to suggest we at least partially backfill the newly dug trench as it is quite near the wall and if it remains just a trench for example say 18 months it might weaken the wall's structure. If he says that's OK, we'll probably backfill completely to be on the safe side. The other BCO said we can't backfill as it would mean we had not commenced work. We are not doing any concreting at this time. The tree stump situation is interesting so I'll post as things progress. Next thing BCO.

New trench showing Holly tree roots.

Diggerman arrived at 8.15 am. 8.15 Diggerman arrived. I checked with him what he was going to do and explained that I was concerned about whether the rear elevation measurement on the drawing matched the space available. I have had large laminated plans done so that they had something clear to refer to. 9.30 (After tea and biscuits) they had drawn the southern elevation and I went to check. The measurement across was approx 13 m and we needed 14 to accommodate 12 m elevation with 1 m each side. What they had marked out (and I’m sure would not have consulted me about before starting to dig) was totally off the mark The plot is not square and to do it the way they intended would have made it very difficult for a car approaching the garage doors to drive in without having to negotiate. The diggerman boss kept referring to me being a “whittler” and fusspot. I said surely it’s better to agree on the building’s position before the excavation starts. This is what I mean about the way men in these sorts of trades still regard. It gave me a headache having to stand my ground so firmly. 10 am and not started digging. The BCO has just turned up and not pleased as the trench has not been dug. When I arranged the visit with their office I said I would phone the BCO when the trench was ready to be inspected but the person who did the booking failed to make a note of this so I am in the bad books again. He said he’d rebook it for tomorrow. So all my careful plans to get everything done today as regards trench and BCO have now gone awry. 10.30 diggerman boss went to another job and his employee excavated the newly placed trench. Good soil but a lot of holly roots see pic. He also dug around the tree stump which is enormous with some massive roots. He is unable to take it out so will need to be ground out and the stump buster man is coming this pm to advise on next move, which I will report. The photo doesn't show how enormous the tap root is and which runs right across the proposed foundation.

Thank you. So having uploaded the photos is the general concensus that what we are going to do on Thursday (as post above) is OK and we won't be making problems for ourselves when we return at sometime in the nearish future to recommence work.

I don't have a mobile phone so using camera. I don't upload many photos so can usually manage. The stuff that has been removed - the sandy coloured part - is crumbly between my fingers, but not fine, and is full of bits of stone. I was unable to push a pole into the bottom as I didn't feel safe. I can't see any clay but I am no expert. Do the pictures help - I've uploaded another one.

Second photo. (I will poke the bottom of the trench with a pole and get back to you)

Here goes - I think my files are too big and I don't know how to reduce them. Yep, it's saying I'm exceeding something or other. I'll do another post.

I would say dry sandy coloured with stones in it. Would a photo help, bearing in mind I only seem able to add one photo!!!

Hi and thank you. Does all this apply if the soil is not clay. We have good soil and the trial pits dug at 1.2 m have no water in them even though it poured most of last week. Also no caving in of either pit. The BCO has said the fill should be 1.2 m deep throughout with him assuming the tree stump is removed or ground down. The diggerman is coming on Thursday to refill the trial holes and dig one trench (south elevation whereas stump is north elevation). BCO will inspect the trench and we should receive a commencement notice, which is what we are seeking (before 15 June 23). Following the trench dig, the diggerman will try and remove the stump by digging around it which will encroach upon the proposed northern elevation foundation area. If he is unable to remove the stump he will ask a grinder to grind it down (he will be able to go deeper as a result of the work done by the diggerman). Because we are not digging the northern elevation trench at this time I am trying, from your drawing, to establish whether what we intend doing will marry up with your suggestion ie dig around stump and either nudge or pull out (unlikely I know) and if unsuccessful employ a specialist grinder to grind it down as much as possible. The area will have time to settle as we are not undertaking further work at this time. The drawings are really useful and we shall refer to them in the future but I would like to be sure the work undertaken this week in removing the stump will not prevent us following your plan at a later date. Many thanks and I have my camera ready.

Update I'll dispense with all my frustrations this week, mainly getting groundworker to give a firm day/time and then awkward BCO tel con when he was very offhand with me. In the end, the trial pit excavation this morning and the inspection by the BCO turned out to be a pleasant experience. So two trial pits were dug to 1.2 m this morning. The ground is loam and is great, therefore no problem with the tree roots from the trees in the churchyard. The BCO was lovely and helpful when he came out to inspect and is allowing us to dig a trench the length of one side of the elevation - he emphasised that this is a concession to enable us to have deemed to have commenced work before 15 June. Digger man coming next week to backfill the trial pits and dig one elevation trench 8 m x 1.2 m depth (BCO said all trenches to be 1.2 m deep unless we hit anything unusual). Therefore no especially deep trenches where the stump is. He says once dug, we can't backfill the trench we are digging as this would in effect mean we had not "started" so at the moment we intend covering the 8 m length with OSB boards and strong plastic sheeting. (I suppose we could backfill once we have confirmation of commencement?) The digger man will also excavate around the tree stump as much as possible and then, I think, get stump grinder man in. He doesn't seem phased with it at all. All in all a successful day and fantastic news about the loam soil. From this experience I would say trial pits are a must. I'll report further next week after trench is dug and tree stump out, hopefully with photos.

After your comment I emailed the BCO and he confirmed that they will inspect the trial pit and will request a soil test only if necessary. So thanks for that, all being well you have just saved me £70 incl p&p.

OK - got it!! We are to going to attemp to remove the tree stump long before digging the trench which is why I couldn't quite get it. I suspect we shall also need a stump grinder. Thank you.

Hi - I am having difficulty imagining this but will copy it and print off to see if anyone can relate it to our stump. At least it proves there's a way around it. Thank you.

Just to say that the experienced groundworker is coming this week to take out the tree stumps with his machine - or he will at least give it a go without damaging the wall. I asked if the hole remaining could be used as a trial pit for a soil test as there would then be less disturbed ground. He said no as there would be roots and stuff in it - not sure that makes sense. What he went on to say is "you need to get rid of the stumps and then fill in the hole as though they were never there otherwise we'll run into problems, like last time, with them wanting deep trenches." (The Stump Remover man said much the same in that he whipped out trees before getting involved with Building Control on his own project). I said the BCO has already seen the tree stumps and specified deeper trenches but we need a soil test to check out the plasticity first. Surely it's in my own interest to make sure we get the footings right to avoid future problems. Anyway I will report back on the attempts to extract Mr Stumpy from our garden.

When you say backfill with stone, do you mean stone chippings. We have a lot of stone left over from rebuilding wall with bags full of smallish pieces. I guess if we used these they will likely have voids and move over time. So can you clarify please which stone is suitable. Many thanks.

Thank you. Are you recommending grinding out the stump in preference to removing the whole stump and roots where accessible with a digger (if that's possible). The stump removal man who came out yesterday to quote said he thought a digger would not be able to do the job. He would grind out the stump and put the shredded material back in the hole so there is nothing to take away (which sounds unsatisfactory to me). As well as the foundation we also have a drain running along this elevation. My thinking at the moment is to try with an excavator with an appropriate fitting and if that works refill the hole with the soil from the trench which is to be dug at the opposite side of the site. This will have time to settle and be constantly refilled and compacted until we are ready to recommence the build in the future. At the moment we just want a commencement notice. So to remove the whole stump and roots or grind down the stump - that is the question .......

I've looked at the distance calcs on the NHBC website and WOW what a difference that makes with a moderate water demand tree - no mention of an SE design and suggesting a trench depth of 1.85 m so with some reinforcing rods a 2m depth might be acceptable for the full length of the elevation with the stump. It does give coniferous trees in both high and medium demand tables but I agree with you that it has been felled 2.5 yrs and has probably died and won't be needing that much water. I'm sure it was a leylandii tree and it was about 20 m tall. The tree in the church grounds is 10 m away - 20 m tall and is the same variety. Thank you so much for pointing this out to me - absolutely great advice.

As I mentioned earlier, if I follow the NHBC distance calculator for medium plasticity/high water requirement tree, the footings are over 2.5 m deep and would require an engineer designed foundation (the stump being right on the footing area would impact I think on at least 3 of the elevations as regards the depth of the trenches). I intend amending my foundation sketch today using the 2.5 m max depth where required). I assume engineer designed would mean piles, so if I employ a SE he may be "duty bound" to say piles are necessary because of the requirements of NHBC. If I phone the BCO he may say to put reinforced bar in but I wonder what depth he would suggest for the trench eg 2.5 m? Best case scenario : Remove conifer stump in total if possible. Soil test comes out at medium clay plasticity and we know the conifer is a high water consumer. (Test cost around £65 last time - 9 yrs ago). Work out trench depths required from tree distance table with 2.5 max depth where required. Reinforced bars, or concrete lintels down the north elevation where the tree stump is. There will be a lot of ready mixed concrete needed but at least I'll know in advance. Discuss above with BCO to see whether acceptable. Does this sound OK?

Well, where to start. Thank you all so much. Two detached houses were built lower down this site in 2013-2015. The site furthest away from us eg 100 m away had medium plasticity clay and masses of it - and it was pouring with rain when the trenches were dug. I do know there was a pond in close proximity many years ago. Everything with the foundations was done retrospectively which left the trenches open longer for the elements to play havoc. No preparation was asked for or done beforehand. Hats off to the lovely builder and the warranty inspector. The other house (built first) and nearer to our house seemed to have no problem with their trenches but I think that was more because no-one asked or knew to ask. A row of sycamores within 2 m of their footings had been totally removed 12 months before they started and I don't believe they bothered with trial holes/soil test. The footings were approx 1 m depth. They have a wooden suspended floor. As far as I know, 10 years on, they have had no problems. We live in South Yorkshire and I am expecting to find clay. Some members will be aware of our situation ie excavating one trench to get a commencement notice before 15 June deadline for change in Bldg Regs. The stump is on the north elevation and the trench to be dug is on the south elevation so this gives us time to sort out the stump problem. However, we don't want to be digging a trench only to find out when we return to finish the footings that we need piles - hence why I need the stump/footings situation sorted and a plan agreed before any work is started. My initial draft plan of action is: Stump remover chap coming out tomorrow so I will get his opinion about removal of the stump and a quote. I'll email/speak to the BCO on Tuesday and get his opinion about the stump removal and advice on footings in that area. Would it be wise to pay for a foundation plan to be done by a structural engineer, then I have something to refer to and insist on. I still find some "people" taking instructions from a woman doesn't always go down well. When the stump is out, could we use this as a trial hole and take the sample from there for the lab test. We could do the same with a holly stump on the southern elevation. Very happy to put reinforcing rods into the concrete and again a SE plan would help with this I would imagine. If we get to the point of digging the one full trench we are now thinking it would be wise to do the concrete fill and then cover lightly with the excavated soil. I'm not sure how this would affect the future fills ie where it joins. Again, the SE presumably would advise on this. If anyone has anything further to add or suggestions on what else I should do, I would be very pleased to know. I can't emphasise enough how much this has helped me. I will post updates regularly and photos of any work done.

I did measure on Google Earth and then on the ground as well. Rowan and pine not near each other. I've looked at the distance calculator on the NHBC website and the one metre distance calculation would apparently require more than a 2.5 m deep trench and therefore should be designed by an engineer. After reading this I thought I should go back to the BCO for advice but not much point if they're not qualified to give reliable advice - which has been my experience so far. It is the large Conifer stump I am concerned about and how to get around this with the footings. Will Nick's advice above: "Needs digging out and the roots to the neighbours side cutting and leaving there. Extra-deep fill trench where you dig down to the bottom of the root ball." be feasible or are we going to have to consider someting like piles. I've contacted a stump remover company to see their view on removing the stump but really unsure now about the footings. Thank you for everyone's time.

Thank you. I did wonder about the ability of the mini digger to get it out - it is a massive stump and actually looks even bigger in the flesh than on the photo. I think if they tried to push the stump there would be a chance of the wall falling down. Ok - I think I'll firstly get the advice of a stump remover company ie get their slant on things and whether a grinder will be able to remove the area of the stump that is in the way of the foundation trench, say for example slicing the stump in half. I'm assuming a grinder leaves much of the stump in and just goes below the surface, but have never seen this done. Diesel maybe .... I am a bit worried now about this stump. I will post what the grinders have to say. Thank you again.

Never a truer word spoken. I absolutely rely on this site.

Well, thank you both and I'm so glad I asked. The tree was felled 2.5 years ago and treated with stump killer and has been covered with black plastic since. Our neighbours are a school and behind the wall that you can see is a 1 m gap then school fence, so we won't be affecting anyone else. The BCO didn't seem bothered about the tree stump, neither did the groundworker who just said he would try and get it out with mini digger and then if unsuccessful, would get someone to grind it down. He was concerned to be fair about the wall. We have other trees to consider, Rowan and conifer which sit in the Church grounds next door. These are on a different elevation and the BCO said we needed 1.2 m deep trenches in a couple of areas because of these trees but didn't comment on the big tree stump. I have been out measuring distances today and will do further calculations as to required depths/steps. As regards the large stump, I'll use the one metre distance calculation as suggested and also check on the use of clayboards and reinforcing rods down that elevation. I honestly find it unbelievable just how blase the people are doing this sort of work every day - I haven't met one "professional" person so far whilst doing this project who I can honestly say I have any faith in. I was in a situation some years ago where clay and trees were involved which required distance calculations, clayboards and rods and it was the Premier Warranty Surveyor that insisted on these (and upset the BCO). No advice given beforehand by anyone to help prepare before starting work - all done on the hoof in the pouring rain with the trenches falling in. At that time I knew nothing and wasn't aware I had to. 9 years later nothing has changed so I am trying to consider every eventuality before a start is made. Thank you for your advice and any further ideas/advice would be appreciated.