My client wants to deepen the basement approximately 16 inches on a 1900 victorian with a stone foundation. The stone thickness measures approximately 20 inches. The current basement floor is concrete, believed to be a 2 inch thickness. The existing dimension from floor to bottom of joists averages around 6'-8", with the client wanting the ceiling height to become 8'-0". What kind of conditions at the footing am I likely to encounter once the excavation is started to remove the old floor and deepen the basement? I am thinking that a one-foot wide stem footing at the inside perimeter of the foundation will be needed to make sure it is stabilized. I've told the client he should also put in a perimeter drain and a sump discharge. Does anybody who's done a similar project have some advice?