The basement foundation walls support the home. When replacing these walls, the home needs to be supported securely. If you plan to replace the walls of the entire basement, the home will need to be lifted while the old walls are removed and the new basement foundation constructed. The project requires specialized equipment for lifting the home as well as constructing the basement walls. It is usually left to construction professionals who specialize in this type of work.
Place beams under the house. Place the beams perpendicular to the floor joists and about 12 to 20 feet apart depending on the size and weight of the home. Disconnect the electrical and plumbing connections between the basement and main level of the home.
Place hydraulic jacks under the end of each beam and lift the home off the existing foundation. Raise the jacks evenly no more than an inch at a time. Place blocks under the beam ends after the house has been raised to the desired level.
Demolish the old basement walls. Determine the quality of the footings and demolish if they are damaged. Remove the debris from the basement foundation walls from the work area.
Expand the basement excavation by about 2 feet in all directions. This creates a workspace on both sides of the foundation walls. Stockpile this soil near the home, and return it as backfill after the foundation is complete.
Form up new footings, if necessary, in a position directly under the home perimeter. The footings should be poured in forms set on undisturbed ground and reinforced with steel rods. Allow the footings to cure overnight before removing the footings. The concrete footings reach full strength after about 28 days.
Build the basement foundation walls above the footing. Build the foundation walls using concrete block or poured cement as desired. The foundation walls can be the same height as previous walls or higher or lower, depending on the owner's preference. The foundation walls need to have areas to allow for the beams holding the house in place.
Lower the home onto the foundation. Reduce the height of the jacks evenly so the home settles uniformly on the new foundation.
Remove the beams from under the home. Reconnect electrical service and plumbing. Fill the holes left in the foundation to accommodate the beams with concrete blocks or basement windows.