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Last time I did something very similar- insurance asked for a JCT.....which my architect said was in place, but miles afterwards it transpired it wasn't and they never asked to see the document. I am using a turnkey builder for this & don't have architect managing, but want to have all bits in place before. Is the public liability the only think they're likely to need? And what is a JCT (in brief).
Oh, I should say it's fairly minor works- no extension & very little structural. Re-modelling/ re-wiring/ replumbing of existing space. And one flat to 4 flats.
Ok - then you only need to check that insurance is in place, nothing else.
Can I clarify anything else for you?