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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.

I recently received the results back of a soil survey which I commisioned as a stipulation of planning acceptance. The survey repoort comes to >170 pages and I asked the surveyor to summarise whether there were any issues found. He said that there were no showstooppers, but that within the made ground there was asbestos detected in one sample and lead in another. Since this is a brownfield site and the plan is to demolish the house and build a basement as part of the new structure, I'm wondering what the implications of this are. Does anyone have experiience of problems like this? I'm wondering what cost / delay I may have to factor in.