Subsidence of foundation occurs when there is a difference or a change in the ground conditions or capacity, on which the building is constructed. Recently the most popular cause of reported subsidence has been the dry summers that have caused the underlying clay subsoil to lose moisture, become desiccated and shrink. However, subsidence could just as easily be caused by the construction having been carried out in an area where there is a geological fault, or previous unknown hazards such as fill. Equally, it could be that the site investigation did not pick up an isolated area of ground with a lower load-bearing capacity.
Structural engineer in Canberra ACT:
The above information is for guidance only.
If you need on-site assessment, contact Antoun from ANH Consulting Engineers about your particular problem or for footing design that suits your site condition.