Substructure Repair

A two-storey resident occupied semi-detached house of solid brick wall construction due to receive external wall insulation.

Cracking could be seen to the external walls on the front elevation and through the render to the side elevation. A buttress previously constructed to the flank elevation had failed to prevent further damage and trial holes established that the foundations were 600 mm wide strip footings bearing at 750 mm deep.

The Bersche-Rolt engineer diagnosed the cause of the cracking as progressive subsidence related movement.

Bersche-Rolt site personnel installed masonry reinforcement to strengthen the external walls and repair the cracking.

The bottom of the existing footings was exposed and in nine locations mini-piles were driven down until the required torque was achieved. Mounting brackets were then installed to each pile to stabilize the structure and the excavations then filled.