Brief: Remove existing reinforced ground floor and pads supporting roof and upper floor in existing building, excavate for 4m underpins install drainage and form new basement.
Solution: Stich drill perimeter to separate existing pads from the structure to be underpinned. Excavate down, installing earth work support form toe and then stem to pin. Back fill working space to keep integrity of building. Follow sequence until underpinning is complete. Install structural steel to ground floor and then bulk excavate to form basement. Once, steel is installed , cast and install basement slab.