macnab wrote: » if memory serves then i think the foundation stones are single layer, depth obviously depends on the size of each individual stone but probably no more than 10" or 12" (inches) My advice is not to dig below the foundation stone level, you dont want those things to move the smallest bit. Have you damp proofed the walls yet? if not then now is the time. You can run a wire around the house that operates off a low voltage or have a silicon type fluid injected into the stonework.