My boyfriend and I are in the process of buying a forclosed 102 year old, very small 850 sg ft house. The house is a story in a half with a Michigan Basement, a main floor, and a loft. It is a saltbox style home. The main floor is very uneven and the floor joist seem to be causing the problem. The house has a stone foundation that seems to be in good shape. The previous owner had put jack supports up in the basement for support, but due to the dirt floor they are sinking. The joist are made of old oak trees and are notched. We will be installing new wood flooring, kitchen cabients, rebuilding the loft and will need to replace the roof. But we can not tackle any of these problems until we fix the joist and level the floor. We would like to do this on our own, we were wondering how we should go about replacing the joist and if we should use I-joist? And if we should use pretreated wood beams or some sort of steel colums or posts to support the joist. We were also courious to know if we can dig the basement deeper and pour a concrete floor. Our furnace,water heater, and pump are all supported on concrete blocks right now and we would rather have them sitting on somthing more stable.