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'Forewarned is fore-armed' say some. Others 'do your due diligence'. Bottom line - do some background research. Here's mine. (With as many internet links links in as I can to help you with yours) If you can pick a hole I what I write, or see that I've missed something, I'd be so grateful if you could tell me. Method We already know that we have to pile. Does the SI report give a hint at which type of pile? Have a look at this Phase 2 SI Report: Concrete Design page 12, point 7.4: (SI = Soil Investigation) Phase 2 S.I. Report - Bay Horse, Lancaster - G15002b.pdf '... therefore the most practicable foundation type would be a bored pile solution [...] on this basis, concrete in contact with the ground may be designed to ACEC Class DS-1 AC1s of BRE Special Digest 1 - Concrete in Aggressive Ground...' So now we know: they need to be concrete of a certain spec (Help!... no idea what the spec means) and that the piles should be '... sleeved in the upper portion to allow for ongoing settlement of the fill...' (Point 7.3 page 11). What a difference a bit of research makes........ read on There's no substitute for a good SE: one who engages with the customer's needs rather than merely doing the job (PM for details if you like). One line in their email to me suggesting we use a form of piling that is a good deal cheaper than traditional piling (Surefoot). And, in one sentence the SE had potentially saved his fee. They cost about half or less than traditional steel piles. Initial conversations with the company lead me to go and have a look at an installation. Here's what piles (if you can call them that) of that sort look like. So, after checking that there was no conflict of interest between the supplier and the SE, we sent the detailed information to Surefoot. Disappointment. Our ground (see the SI report above) is too 'made-up' . Hmm, back to square minus-a-few. Lesson learned? Keep looking. And that means hours on 'Tinternet. Hours of time apparently wasted. Hours of time which at the time that 'feel' wasted which could be spent doing a million other things . And then a post from @Calvinmiddle suggested I look at national piling contractors. And that lead me to Town and Country Vibro . Instantly another set of unknowns and another research blizzard. Blizzard? Yes, that's how I feel.... I can see a few millimeters in front of my face, I can just about read my compass, I know where I'm going but there might be a crevasse one step in front. What in heaven's name is a stone column? Can it really be as strong as a pile? Why the Heck does the SE specify a safety factor of 2.5(ish) What is 'ground improvement'? How much? Why all the sales guff full of well-know management waffle? What does it actually mean? I really wish there was a Course in every Management Department in every British University which had a compulsory course called Cut_The_Shite_Out _Of_Sales_Speak. It just gets in the way. So, it's hours of YT videos.... bottom feed (my favourite) top feed (mehhhh) vibro (hmmmm) Gordon Bennett is it that quick? A few phone calls later and I'm standing on a building site somewhere in deepest east Lancs with Dan. For reassurance you understand. And a chat with the rig driver. Which lead to a quote. (Cheaper than Surefoot) Which lead to a site meeting at our place, which was well handled: there was a proper check list - whereas up to now a site meeting went something like this... "Well mate y'll need 5 meter piles and we'll do the calcs for ya, 'kin SE's they're a waste of time and money" A swift, polite Bye Bye. Or (and this takes some believing) "Your plot's the same as all the others round here: you'll need four meter piles , and I reckon the jobs going to cost you £20K" He had neither asked for nor seen any SI information - it was offered but he said "No need to bother son". It was the epithet 'son' which really got me. On arrival on site, he got out of the best kept top-line Mercedes I have seen for a long while. I was almost rude in showing the contractor the door. Almost. Piling design: TCV did that, and sent to our SE (Tanners) and that's where we are now. Stone columns (ground improvement) is the method. We need a piling mat: and that's another story.

Making a sensible guess at what it might cost We already know from the previous Blog Post that , at the moment, Stone Columns is the preferred method. So, it's straight to SPONS for a look-see. Here's a link to the book, it's expensive, but it's saved me more money than I care to count - and here's the twist - it's increased my level of confidence no end. Because I know what a reasonable price is likely to be. Here's the link to a post I made about it recently - goes into more detail than I do here (I don't want to repeat myself, people get bored so I'm told). This blog post will illustrate how useful the book can be: or how useful it is to me. SPONS - the hardback book has a few pages on piling (Chapter 7 p.238 et seq), and when you buy it you also get the licence for an online version - and that allows you to search for 'piling' across the whole book. Suddenly you are aware of all sorts of things to do with piling, as well as the charges directly attributable to piling. So, for example I find that a CFA team consists of 3 blokes (sorry 'people'), their rates of pay and so on. Very absorbing. And that's useful because it begins to redress the 'expert' , 'customer' imbalance. Fuller information promotes partnership and engagement. I accept that some may not want that, but I do. Many piling methods need a piling mat. Some don't (Surefoot for example) See also my previous blog post So the key for me at the moment is how to sort out the piling mat. The Basics There are two elements to piling: the piles themselves and the piling and the area which needs to be prepared for the rig. It's called a ' Piling Mat' A piling mat is simple: its a level area about 2 meters wider than the plot so that the piling rig can strut its stuff. (I'll post the exact specification later) So in our case that's about 14 meters by 14 meters. That needs to be costed. Here goes: area affected - (10 by 10 plus two meters each side for wriggle room , that makes 14 by 14), say 200 sq m, lets keep it easy for those of us who only just passed maths O Level. The SI report makes it clear that we have at least 2m of made ground everywhere. What's the spec for a Piling Mat? Well, if you pay £45:00 you can find out. BRE (2004) Working Platforms for Tracked Plant: good practice guide to the design, (etc.) For costing purposes we can have a look at SPONS now (page 163) '...excavate to form piling mat; supply and lay imported hardcore – recycled brick and similar to form piling mat...' Spon's Architect's and Builders' Price Book 2016. CRC Press Assuming the site needs to be dug over to a depth of 1 m and then compacted, I need a price for 200m cubed . That translates to a price of £1600 to £2000. First quote £11,000. Yeah, right. The piling itself: The SE will tell the piling company what they need to support, and the SE needs the Soil Investigation and the Topographical survey To Be Continued