I am thinking about laying a concrete floor in my cellar to convert it into a utillity room. The current floor is made from brick and is far from level, it is higher in the centre than at the edges. This posses a problem as my head is already touching the celing. I understand I will need to remove the brick work and may have to dig down far enough to accomadate hard core through to a screen, depending what is underneath. This is shown in the ground slab project, however it doesn't give depths for each layer can anyone help, as I would like an idea how far I would need to go if I decided to contract a builder to carry out the work.