The timber floor of this 1930s federation style residence in Mosman (Northern Beaches, Sydney) was sinking. In fact, the vast internal timber floor was sinking so much that if you were to place a ball at one end of the room, it would roll into the centre. There was an obvious dip as you walked around inside.

Deeply concerned about the possibility of the timber floor collapsing, the homeowners called upon our skills and expertise. They wanted to find out why the floors were sagging so much and if we could repair them quickly.

Upon arrival, we immediately took to investigating the subfloor area of the house. At over a metre, the subfloor granted our builder easy access from outside.

Inside the subfloor area, we found the expansive timber floor propped on top of dozens of brick piers with temporary wedges placed on top to fill the gap between them and the bearers. These load bearing piers were set into the ground about every 2 metres apart and also held up partition and stud walls too.

These brick piers were sinking due to eroded soil.

Leaking pipes and insufficient drainage under the house had directed water straight into the subfloor area. This had exposed the footings of the house and weakened the piers. The 8 brick piers that held up the living area's timber floor had sunk the most.

Because the house's floor was so expansive, it bowed more than any other floor we had seen in a long time.

To avoid damaging the timber floor we used a hydraulic jack system to raise and re-level the floor back to its original height. This also took the pressure off the brick piers that sat underneath the floor.

Having taken the pressure off the brick piers, we were able to work on re-levelling them and stabilising the ground in which they were placed. Our proprietary geopolymer resin solution, GeoPoly™, raised the brick piers back to the underside of the bearers and stabilised the surrounding soil for good.

We were able to re-level the expansive timber floor, stabilise the ground and raise the house's brick piers in the subfloor area in one day. After we re-levelled the timber floor, the homeowners called upon their local plumbers to seal leaks and repair broken drainage. The homeowners now enjoy level flooring and take comfort in knowing their foundations are stable for decades to come.

Got a floor that dips in the middle, or a ball that won't stay put? A free assessment measures your floor levels, checks every pier for contact with the bearer above, and tells you exactly what's moving.