Foundation Replacement
In cases of severely deteriorated foundation walls, replacement may be the only viable option for repair. In most situations where foundation replacement is required, it involves only a partial replacement of 1 or 2 foundation walls.
Typically foundation wall replacement is accomplished by setting shoring to hold the building in position while the existing foundation walls are removed and replaced. Some minimal lifting can be done to level the building off of the shoring. This is the least disruptive to the utilities of the building as the shoring can be placed as required around utility interferences to provide support for the building above. Also since the building elevation is not being changed (lifted), services such as gas, electric, sewer, and water do not have to be disconnected.
In cases where the foundation walls will be replaced with full height concrete, or if the objective is to gain additional basement height, then the building may have to be lifted. In these situations the shoring must consist of straight continuous steel beams which are lifted by hydraulic jacks. Placing these shoring beams is usually very disruptive to utilities as they must be straight and continuous (no jogging or working around utilities). Both the lifting of the building, and the relocation of utilities, adds considerable expense to the project over what would be required to simply shore the home in position and is rarely done.
Typically with older stone foundation walls, and sometimes with red brick foundation walls, there will not be a footing to construct a new foundation wall on and so one will have to be installed. This is usually not the case with concrete block or concrete foundation walls.
Replacement of foundation walls is typically done with concrete, concrete block, or a combination of the two materials along with reinforcing steel. New drain tiles are placed at the exterior perimeter of the footings and connected to the existing drain tiles, if there is any, or brought into the basement and tied into a new sump pit. The exterior of the wall is then damp proofed or water proofed depending on the type of foundation wall construction.