Underpinning Sydney

Underpinning strengthens the foundations beneath a home so they can carry the structure above. More importantly, it stops subsidence — the ground giving way under your home — before it does more damage to the walls, floors and frame.

Traditional mass concrete underpinning works. It's a real engineering solution. But it's expensive, disruptive, and most Sydney homeowners aren't told there's a non-invasive alternative that does the same job in a fraction of the time.

GeoPoly™ resin injection is what Buildfix uses to underpin Sydney homes. Coin-sized holes, no digging, the foundation lifted back towards level in a day or two. The family stays in the house. The garden stays intact. The wall cracks start closing as the foundation settles.

Sydney sits on more soil types than almost any other Australian city — reactive clays across the Northern Beaches, Inner West and Western Sydney; sandy non-cohesive soils through the Eastern Suburbs; sandstone bedrock in parts of the North Shore. The cause of subsidence is different in each area, and the right fix follows the cause.

The single most common pattern across Sydney is reactive clay shrinking in a long dry summer, then expanding when the autumn rain arrives. Older homes with shallow brick or stone footings — common in the Inner West and across the Northern Beaches — feel that movement first. A leaking stormwater pipe, a thirsty tree close to the footing, or a disconnected downpipe washing water against the wall will speed it all up.