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We are working on a new self build project for our domestic residence, we need a company to assist with Piling for the foundation. We need 58 piles in total as per structural engineer drawings. We will appreciate any kind assistance. The location is in Leicestershire. Kind regards

Hello everyone. I'm a newby and I'm looking for sound advice here. I'm wanting to build a house on a plot of land that is next to the river Calder. I know I must be at least 8m away from the bank. Is it advisable to get borehole samples when I've already decided to put piles down?

Hello everyone. I'm a newby and I'm looking for sound advice here. I'm wanting to build a house on a plot of land that is next to the river Calder. I know I must be at least 8m away from the bank. Is it advisable to get borehole samples when I've already decided to put piles down?

Hello all I have a 1960's riverside bungalow built on a concrete slab, raised about 4 feet above ground level by concrete piles. I am looking into getting the piles surveyed, with the idea of building a new dwelling on the existing slab. This is only really an option I want to explore if the build would be VAT free. If it's not, I may as well take up the piling too and start from scratch. However I'm confused as to whether it would be subject to VAT or not. The HMRC guidance suggests if you retain only the ground floor slab of a building then you can avoid the VAT. But it also goes to lengths to say you can't retain existing foundations. Do the piles count as foundations from a tax viewpoint or not? Grateful for any advice. Please feel free to indicate if you've had experience of anything similar. I will get pro advice before the build, but in the meantime would like to feel quite confident about this point.

I know this has been discussed at some point, but it was on a very tiny slope and I have found nothing about anyone trying near a Watercourse or similar. So my question is: Is it possible under any circumstances to build Passive Slab on a slope of ca. 1.5 meters next to a Watercourse. My guess is "No" But i still think it s worth a try, as this would be a good slab solution. Here is some measurements (see Pic below) . House will be on a slope of 1.5 meters over 21 meters distance. But the bigger problem probably is the Watercourse directly next to it - oh, and I forgot- a few trees as well. I will ask Structural Engineer the same question, but her solution so far is not really a cheap one (Pile and Beam with slab , first quote coming is : 47000£+VAT ? ?) Thinking by now that it might be best to leave concrete out and just put suspended Timber Floor on Screwpiles. Anyone in here got experience with this? Even Though Helical Piles are not cheap, might still end up much cheaper. Has anyboday ever tried installing helical Piles themselves ? I just had a quote for the Piles themselves - just material - 1600mm length excl. shipping for 15USD each (100/pallet) , seems cheap enough to me ?

I didn't realise quite how long a while since the last blog entry so time for an update as I'm on an admin day today, not least for the electricity supply which I'll come onto later. So, what's occurring? I'll start at the bottom and work my way up: Groundworks - the groundworkers arrived on site the day after the last May bank holiday, 29th May. They took the roof off back in April to sort out any potential bat issues and now they're back doing the main job. The old concrete garage block came down first. The roof panels have asbestos and have had to be properly disposed of, which has been done at a reasonable price of £650 rather than the c. £1300 I was looking at a couple of weeks ago. All done properly and I have my disposal certificate but without having to resort to sending stuff all the way to Swindon and get charged for 2 tons when it was just over one. A small result; still expensive but less than it could have been. My ground worker arranged this with one of his contacts; PM me for details if anyone local needs the details. The concrete sides of the block are all down but we've left the floor in place as it's a ready made hard-standing for everything that will be arriving on site over the coming months. It's mainly parking, portaloo and site cabin taking it up now. I will need to get some hardcore compacted down going further into the site as I'm not sure it will stand up to all the heavier construction traffic that is due. Demolition of the building will be finished this week, but there's still the old septic tank to be dug out and a bit more concrete from where there were sheds in the past. Next up is digging out for the insulated slab, drainage and services, not to mention the piles. I have my groundworker until the end of next week before he's due on another job, so we should get a fair bit done by then. I reckon the initial excavation will be a little rough until we've established the levels, which seems a bit chicken and egg to me at the moment. How can you mark out how deep you need to go when there's a whole lot of earth in the way? Fortunately, there are some useful markers on the site that I can use as references for the setting out of the perimeter but I will get everything checked out before the piling guy arrives and have any remedial excavation done for that. Speaking of piles....I've ditched the idea of the helical screw piles. Not because they weren't lovely enough, but because they were outrageously expensive compared with other, more traditional systems. The initial design drawn up by my SE would have cost more than £42k for the helical screw piling system which seemed like mad money to me, probably because it is. I had a chat with a contact and he said that very little of this kind of thing is done now, certainly on house projects. When it first came out it was embraced with open arms by the telecoms industry for ease and speed of use, but they have dropped it almost entirely now on cost grounds, and I can see why. My initial quote for CFA (continuous flight augur) piles came in at just over £15k which was far closer to what I was expecting. I reckon that in the end, with SE fees and everything it will come in at around £20k for the piles. As mentioned in a previous entry, the alternative was to dig to at least 2m depth over the entire footprint, which in itself is an expensive exercise due to the cost of muckaway (I estimate an additional 15 tipper loads), so swings and roundabouts, the piles aren't as extreme an option as it first seems. I've used Mini Piling Systems Ltd for the piling system - nice people, easy to deal with, based in Bath, will travel. I should add that because these are mini CFA piles, as long as the ground is dry and reasonably level when they come to put them in (July), there is no need for a piling mat as the rig isn't considered a large one. Moving upwards, the other thing that has slowed is getting drawings from holy trinity of architect, SE and MBC to the sign-off stage. The SE has been very efficient and have turned things around very well. The architect and MBC have been slower, but I'm going to hold back some criticism because were I in the shoes of the architect, I would probably be doing this amount of nit-picking on behalf of my client and I'm sure that I will be glad of it. As ever, just because an architect designs a house and it gets planning permission, that doesn't necessarily mean that it can actually be built. In my case, there have been delays in getting the small details that can be glossed over in the desperation to see physical progress and having something coming out of the ground, and this is what the architect has been pushing back on. They are determined to make sure that the proportions of rooms are consistent with the original design. For instance, the ground floor ceiling height has been raised so that the large open plan downstairs doesn't feel oppressively low due to its large area. As a result, most of the ground floor windows will also need to be increased in height as will the front door. This all has a knock-on effect, hence the delays. There has also been back and forth over the balconies and warm or cold roof construction and the parapet wall around them; we're not quite at the end of this but pending a response from a supplier, we are close. The issue is that the common solutions to ventilating the cold roof would look ugly. Everyone has gone to a lot of effort to make the house as good looking as it can be and it would be a shame to rush through this detail and then sit looking at ugly vents on the balconies for ever more. But, tick, tick, tick, more time passes. By far the biggest issue is that until these details and corresponding drawings are signed off and I pay a stage payment to MBC, my manufacturing countdown doesn't start. Standard time for MBC to get on site is minimum 6 weeks, this time of year more like 8 so I'm realistically looking at end of August or early September. Then there are the windows to go in and roof to go on. I really, really want the build to be weather-tight before the weather breaks in the autumn, as it will. Moving on to making the building work as a home, and for construction to actually take place, I'm sorting out the electricity supply at the moment. There is a live supply to the site as there was an existing dwelling there. Last year I contacted the DNO and had a service alteration done, which basically chopped the wire running into the bungalow and moved it all into a box on the pole with the overhead cable running down it. I rang the supplier at the time and advised them of the changes being made and arranged for one of their bods to come along and collect their meter. Sadly, they didn't turn up for the appointment, so now their meter is buried at the bottom of a pile of builder's rubble in the local landfill site. This put all sorts of twists into their collective knickers and it's taken the best part of a day to sort out how to re-establish the connection. It turns out that what's needed is a temporary building supply and this is always done through the commercial team. I've been quoted up to 12 weeks for the whole thing, but this is if you are applying for an entirely new connection, not just to get a meter installed. Even so, it could take around 4 weeks. We shall see. In the meantime, I've (for the time being) decided on getting my kitchen from DIY Kitchens. I've planned it all out and know what units I want and where, so I'm not going to think about that again for a while. I do, however, need to start thinking about lighting schemes and bathrooms/wetrooms as I've made very few decisions on these. Needless to say, there is a huge amount of other small detail going on but little of which can be done until the final drawings are in. Never a dull moment, though, my groundworker has just called to tell me that they have bent over a water pipe to stem the healthy flow of water that was coming out of it when they went to remove it, despite Wessex Water having sworn faithfully to me in February that the water was all turned off at the meter and that nothing should be coming out of anywhere. Off to make some more calls and demo photos to follow soon. Ta ta for now.

The slab team from MBC arrived on site this morning. It's like having the building version of whirling dervishes who've just dropped a few speedballs. My word, they make progress! The team is headed up by Harry and he has 3 others in his team, but this will fluctuate a little over the course of the job with Harry needing to have a look at another job for most of tomorrow then the younger lad taking some leave to go to a music festival. Tsk, the youth of today! He worked like a machine, though, apart from the bit where he nearly rolled over one of the piles as he was looking in awed astonishment as a rather attractive young lady farmer drove past on the nearby track in a JCB that was most definitely bigger than the roller machine he was on. I don't think it was the vehicle that caught his attention so much as the driver. Sniggers all round. I arrived just after 8 am this morning and the first lot of hardcore had already been delivered. In total, there were 4 loads of type 1, but I piggybacked onto this and ordered an additional load (paid for by me) which the team will then spread and roller for me in the area beyond the bucket in the above photo, which will create a nice level area for the crane when it arrives to bring in the timber frame. I've had really good luck with the weather so far and hope it continues, but if it rains between now the completion of the timber frame, the site will turn to mud PDQ and slow things down horribly. Once the hardcore was going down and getting compacted, the piles were cut off to the correct height, leaving the rebar in position, ready to be tied into the beams. I have no idea what you call the digger thingy that they are using to move the stone around the site, but it's an impressive beast. It looks a lot like the bottom of a tank with its caterpillar tracks and then something a bit more transformers-like with its swivelly cab and arm. Either way, it was mechanical poetry in motion when driven by someone who clearly knew what they were doing. The team will have been working till 7pm this evening, so they will have got all the hardcore down and compacted and were going to start on the sand, if they had the time. The first load of sand arrived about 4.30 this afternoon, more to follow on tomorrow morning. As well as working 12 hour days, Harry has already had a chat with the neighbours to let them know that they will be working over the weekend, too, on both days. The insulation is due for delivery tomorrow and they will be putting the pipes that carry the service cables into this, along with the UFH pipes. I'm not sure when the steels will arrive, but that must be also imminent as the piles will need to be tied in before the concrete is poured. The building inspector is coming on Monday to check out everything before the pour. For interested parties, THE CONCRETE POUR IS CURRENTLY SCHEDULED FOR TUESDAY. I've read a couple of horror stories and some not-quite-horror-but-not-very-nice-stories about uneven slabs, so I've told Harry that before they leave site, I need him to demonstrate with a laser that everywhere that a wall rests is absolutely level and within tolerance. Harry is a man of few words and he didn't quite bat an eyelid, but I explained that I would much rather that something like that is demonstrated rather than just verbally assured. He seemed fine with it. So, one final picture of the hardcore going down, from the garage side of the house. More blow-by-blow action to follow tomorrow.

There's been some miscommunication re. my piled foundation design with the result that I now have 2 options: 1. The piles are tied to the ring beam with the result that there is what MBC describe as a 'minor thermal bridge' for each pile. The upside of this design is that I don't need to spend approx £5k on cellcore for anti-heave and perinsul blocks for the load points of the superstructure to sit on. 2. The thermal bridge is broken by not tying the piles into the ringbeam; I will need to have cellcore and perinsul blocks. I don't know the cost of the latter but it's unlikely to be cheap. MBC haven't specified what they mean by a 'minor thermal bridge' so it's hard to make an assessment. Obviously, saving £££ on the anti-heave and additional insulation is attractive, but I don't know if it's a good long term decision. Any thoughts from the hive mind?

Chance meetings, research and no fear of being nosy have stood me in good stead for many years and it's proving no different with getting a house built. The 'dig deep' thing was bothering me, mainly the thought of having to go down 2m over the entire footprint of the build and the cost of all that muckaway, as well as the risk of it all turning into a giant, muddy swimming pool during the process. I will freely admit that up until about 10 days ago, the thought of having to get piling included in the build struck terror into me due to what I perceived as the potential cost and complexity involved, all down to my own ignorance about piling. As a new comer to the world of self building, the only thing I'd really picked up on in the past was hearing about remedial work to houses that were falling down and the huge amounts of cash involved. I'd already had a mooch around this site to see what I could see on the matter of piles and had a look at @recoveringacademic's blog and his comments and rapidly lost my fear but not my trepidation over costs. I also had a visit to the build site of another BH member who has been very helpful and encouraging. It was a spontaneous visit as I was really, truly just passing by his site on the way to my own, but his structural engineer was there at the time so I stood quietly by and ear-wigged, as you do, and then one thing led to another and we started chatting about my site and my clay dilemma. The upshot is that the SEs were really helpful guys and I'm engaging them to design a piling system to support my MBC build and overcome the risk of both lateral and vertical movement that my site is very vulnerable to. I'm also having them design the drainage system while they're at it. They will liaise with the architect, building control and the timber frame company and make sure that my build not only gets out of the ground but stays in the same place once it's done. I've never had an issue with professional fees as long as they are ones that are genuine and add value to a project. In this case, it will be money very well spent and a huge weight off my mind. How best to approach the drainage plan had been vexing me for the last few weeks, particularly as my clay soil means that soakaways don't function. One thing that I think may be worth mentioning is the combination of the passive slab and a piling system. The soil beneath the building is not just highly shrinkable clay, but also very dessicated thanks to the long term presence of a few trees and a super thirsty hawthorn hedge. Although these are all now gone, their long term potential affect on the soil will remain for a long time. In particular, the risk of heave. The piling system will keep the building in place, but does nothing to stop the swelling of the clay directly underneath from pushing up and breaking the floor of the new structure. The SE started to talk about a suspended floor to mitigate against this. However, a few days ago I read a BH discussion where @JSHarris mentioned the issue of an airgap under a passive slab having a detrimental affect on the insulation of a slab so was able to say with some confidence that I wanted the slab to rest on the ground, and my reasons why. The SE was fine with this and all the gubbins under the floor will now include a layer that is a honeycomb structure with the face of the cells resting on the ground so that if it does expand, it has somewhere to expand into without damaging the slab. The helical piles are part of an impressive system - no piling mat, no excavation if you don't need it (I need some to make sure that the floor level of the house is level with the ground), super quick to install and little vibration. This will save a huge amount of time and money compared with digging deep and a far more elegant solution with the dangers of heave solved as well. In all, the cost of the SE and the piling won't cost me any more and it may be somewhat cheaper. The time element is important, too, as the lesser amount of excavation will be much speedier and keep me on track for the main part of the build to take place from end of May onwards, assuming everything else is ready. The cherry on the cake was put in place this morning with full discharge of all the pre-commencement planning conditions. All in all, a good week.

I am now looking at my second plot but the soil survey (from by the vendor) is rather intimidating and scary. I could do with some calming down and some advice. plot is near rectangular 13m by 19m soil: sand and gravel 0.15m to 1.35m depth underlying Gault clay groundwater below 2 - 2.5 metres depth the site has two major trees. "Live roots were recorded within the boreholes to depths between 0.90m and 2.80m 

" Foundations


 recommendation Sleeved piles Driven piles not possible because of proximity of neighbouring buildings "Single 300mm diameter bored piles, installed to 10m and 16m depth at the locations [… ], would have estimated working loads in the order of 170kN and 310kN (FoS=2.5). Different pile lengths, or diameters, from those detailed above would give different available working loads, which could be tailored to suit the working loads required. A piling specialist should undertake final design of piles." Floor slab "The floor slab for the proposed structure will need to be suspended on the piled foundations, in order to avoid differential settlement between them. As the floor slab will lie within the range of influence of mature trees, and desiccated clays are present, the ground floor should also be separated from the underlying soils by a sub-floor gap, as indicated in Table 7 of the above cited NHBC Standards." This all sounds firghteningly expensive and as I read it I thought of the phrase "you're not out of the ground until you're out of the ground". What should I make of this? I have not made an offer on the plot as yet but I suspect that this should impact the price. I would be happy to ping the full report to anyone who'd be willing to give me some advice.

This looks like this today I had a look at my records: January 2014 was the moment we first thought we might have a go at a planning application because our colleagues told us it was worth a try. Many times we were advised (correctly by estate agent friends and others) not to bother. @MrsRA bought the orchard (which the digger is now levelling) in 1985. It's nearly 30 years since there was a glint in her eye about getting a house built here. When we've built the house we'll reinstate the orchard. Put your orders in for Damson jam quick as you like. I can't tell you what a relief it has been to get to today. Piling mat will be finished Wednesday, and the stone columns go in on Saturday. The BCOs (Approved Inspectors) are having a CPD session at our place on that day , so a couple of inspectors are coming to see the stone columns go in, and the piling company Town and Country Vibro is also having a company training session at the same time. Better go and buy some more tea bags.

We need piles because we're on 'made ground'. We've chosen to use stone columns instead of steel piles. So far so good. We need to satisfy SUDS requirements. So, what's wrong with popping (say) four more closely grouped stone columns in our garden to act as a soakaway? No need to compact the stone to 150kN, but we could easily (20 minutes) pop four stone columns in for a few extra quid, and have a soak away. Too simple innit? What have I missed?

My piles are getting a lot of attention. Some say they should be put in with a vibrator. Hmm, that sounds like fun..... So I went and had a look : and wondered if Jimmy Page had a role in piling. Or maybe the designer was on something when he thought of this rig. Talking to the driver (also a Lead Zep fan) he said that it was the best rig he's ever driven. Ya gotta give it to the Germans, there's something annoyingly reliable about them. Now, where's that razor? Must shave my top lip.

Well, whatever size they end up, my eyes are going to water. That much is certain. Here's the thing: our SE has given us a comprehensively specified pile design. More than good enough as the basis for a tender. And slowly, the piling companies are coming round to visit the site, and then submit their tenders. But each company has specified piles of differing specifications; In terms of diameter ; one company suggests 220 mm, the next some 150 mm, and the rest 168 mm Is it simply a case of the bigger the diameter of the pile, the shallower the 'drive' is likely to be?