Townsville Underpinning, House Re-Levelling & Subsidence Solution Experts

Subsidence is part of the earth’s constantly shifting crust and can be naturally caused. However, issues such as soil compaction, loss of ground moisture, excessive excavation, or erosion can exacerbate subsidence. Ground instability causes subsidence, and the damage can often seem reversed as the ground shifts back and forth over time.

Using resin injection ground strengthening, we improve ground compaction. We can then raise and re-level sunken buildings and add support to the ground for soil stabilisation to strengthen the foundation and stop the soil underneath and around the buildings from slipping or moving. We have successfully raised, re-levelled, and re-supported thousands of homes worldwide.

Re-levelling generally refers to restoring something to its proper or desired level. The specific meaning can vary depending on the context:

In construction or home repair, re-levelling involves adjusting the surface or foundation of a structure to make it level. For example:

• Re-levelling a house means improving and re-supporting its foundation or support beams to correct uneven settling.
• Re-levelling a driveway involves smoothing and adjusting the ground to remove slopes or depressions.

Underpinning is the process of extending the foundation of a building to a deeper layer of soil. This is traditionally done by digging deep holes under the footing and filling the hole with concrete.

The main alternatives to traditional underpinning are resin injection and screw piles.

Resin injection strengthens the soil beneath the footing by compacting the ground. Screw piles extend the footings to a deeper layer of soil.

The cost to underpin a footing can vary significantly, and depends on the method adopted, soil condition, accessibility to the failed footing and proximity of other buildings and pavements to the work area.

Traditional underpinning is labour intensive and involves large excavations, so its price does depend on how busy the contractor is. Resin Injection and screw piling have more stable prices.

Traditional underpins vary from $1000 to $4500 per underpin for shallow underpins.

The cost of underpinning varies based on factors like the method used, soil conditions, and project size. Here’s a general breakdown:

• Mass Concrete Underpinning: $1,000 – $3,000 per meter.
• Beam and Base Underpinning: $1,500 – $3,500 per meter.
• Mini-Piled Underpinning: $10,000 – $20,000 per pile (depending on depth).
• Resin Injection: The cost of underpinning a house using resin injection varies based on the size of the property and the extent of foundation damage.However, resin underpinning is generally more cost-effective compared to traditional methods due to its efficiency and lower labour requirements.

Deeper underpins are more expensive as each excavation requires shoring to make the hole safe.

Resin injection typically costs in the range of $1100 to $1400 per linear meter of the footing to be supported.

Traditional underpinning required digging holes next to the footing and then filling them with concrete.

The excavation of the holes can take some time and will impact gardens and paths as they will be removed.

Traditional underpinning could take a few days for a single underpin to several weeks.

Concrete underpins if well-constructed using sound concrete should last more than 50 years.

Resin injection is different to underpinning.

Resin injection involves strengthening the ground beneath the footing, whereas underpinning involves extending the footing to a deeper layer of soil.

There are several pitfalls when using concrete underpins.

In reactive clay soils, if only part of the footing is underpinned then there will be differential seasonal movement between the underpinned sections of the footing and the rest of the footings.

This difference in seasonal movement will result in large cracks forming in the walls adjacent to the areas that have been underpinned.

Another problem that arises with traditional underpinning is poorly compacted soil adjacent to the underpin acts as a water path to the underside of the underpin and can undermine the underpin.