The cost of underpinning is dependent on the size of the structure and the linear meters of walls to be shored up.
Common Types of Underpinning:
- Continuous footing
- Grout injection
- Adjoining neighbours footing as your new footing is going below grade of the bottom of neighbours and by law you are responsible for ensuring no damage to neighbours property.
In a domestic house type scenario You would expect to pay approx $1000/ pier, about $1000 / lin meter of continuous concrete footing installed, about $500/lin meter for soil strengthening using grout injection under existing footing + GST. Establishment cost on site approx $1000+gst.