In Melbourne, soil conditions and past construction practices combined to pose complex challenges get more info. Michael Chen, who has 20 years experience working in Melbourne’s construction industry, was able to help us understand the issue.

Michael described underpinning in terms of strengthening and stabilizing an existing building’s foundation. He explained that “underpinning” is needed when the original foundation cannot support the building anymore, due to soil subsidence or instability. The reactive clays in Melbourne’s suburbs are usually the cause of this. They swell and contract with moisture.

The engineer described signs of a need for underpinning. There are also signs of underpinning, such as wall fissures that appear, unclosed or stuck doors and windows, uneven floors, and apparent wall cracks. He said that while these signs could alarm any homeowner in Melbourne, they are especially common here due to the unique environmental challenges we face.

He stressed professional assessment as a means of early discovery. “Catching these issues early can help prevent more extensive damages and, therefore, higher repair cost,” he said. He described other examples where early actions prevented catastrophic failures. For example, the north-eastern city suburbs where heavy rainfall and intense drought caused ground movement.

Michael then explained Melbourne’s underpinning techniques. The most popular and oldest mass concrete underpinning technique involves excavating sections beneath the foundation before pouring concrete in stages to create a more stable foundation. He also mentioned resin injecting, which stabilises the soil underneath the foundation.

The choice of method depends upon several factors including the severity, structural characteristics and budget of the building. The underlying concepts have been changed by modern technologies and methods. In order to lift and support building precisely and silently, hydraulic jacking has become more popular.

Michael also referred to Melbourne’s stringent regulatory environment which ensures that all underpinning works meet requirements. Michael said permits and regular checks are required. He also stressed the importance of working with an experienced structural engineer to help navigate the complex local building codes.