I'm not sure this is quite appropriate for this site but I'm beginning to have a nervous breakdown with the builders and need some advice please? I've had my ancient conservatory knocked down and am having a new one built that is about 2ft wider and longer than the old one. The builders have covered the original soakaway with concrete as this was right at the edge of the old conservatory and have said I need a new one dug. I thought they would have dug up the old concrete foundation as we don't know what's under it but all they've done is dug down and filled in the 2ft round the old foundations with the new concrete. So I've got a couple of questions.... Is this what they would normally do as where is the damp course membrane going to go? (the floor of the old conservatory was 2 bricks lower than normal floor level and the air brick is one brick above this at the moment but what they have said they will be doing is raising the level of the floor to just over the airbrick). How deep will the soakaway have to be below ground level? and roughly how much will digging a new soakaway cost as this was not included in the price quoted for the work.