We plan to have a 100 year old timber center beam and posts replaced in our basement with steel during a basement remodel. The three posts have over the years sunk about 2-3 inches relative to the foundation walls. Therefore, all my floors slope to the center of the house. In order to replace the timber beam with steel, either the joists will need to be raised and made level with each other and the foundation, or each joist will need to be shimmed or sistered to a level point to properly rest on the steel beam. My contractor wants to first try to raise the joists to make them level. In doing that, he would raise slowly and see what damage, if any, occurs on the two upper levels (hardwood floors buckle, plaster and drywall cracks, windows break, etc.). If too much damage is occuring or seems about to occur, he will resort to shims under each joist. Has anyone had this work done or did it themselves and have any pointers? We had one suggestion of trying to raise the joists very slowly, over a few-month period, but obviously contractors don't want to take that amount of time for a project like this. Any comments would be appreciated. Note -- frame house, 100 years old, unfinished basement, finished upper two levels.