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Australia
A Sign Of Subsidence
What does a sinking floor or concrete slab mean?
Sinking concrete floors or slabs are an indication of building subsidence
Our bespoke solutions for slab lifting and re-levelling methods address the underlying subsidence problem by strengthening the ground beneath.
Our level correction methods can cater to any building size, from homes and driveways to warehouses and transport yards, and are non-invasive, cost-effective, and time-efficient, with minimal disruption to the occupants.
Video
Residential Sinking Floor & Slab
Our Teretek® Resin Injection technology can raise, re-level and re-support sinking floors and slabs.
Watch how our non-invasive, cost-effective technology raises and re-levels a sinking residential internal floor and external concrete slab.
Sinking Floor & Slab Repairs
Before & After Treatment
Houses that need to be re-levelled often experience internal and external sinking floors and slabs.
These houses require their foundations to be re-levelled.
Mainmark’s non-invasive and cost-effective solutions can raise, re-level and re-support your home. Our innovative methods minimise site disruption and are completed within one day.
Features & Benefits
Mainmark’s Solutions & Technologies
Fast
Our technologies have fast curing times and treated areas can be used immediately or without the delays compared to traditional repair methods.
Environmentally Inert
Our technologies use an inert material that is non-toxic and does not leach into the environment or affect the treated area.
Non-Invasive
Our solutions are of surgical nature compared to traditional methods.
Cost-Effective
Compared to traditional methods, our solutions are more cost-effective, with minimal disruption to the area.
External Sinking Floors or Slabs
Outside Your Home
You may also notice sinking or gaps in concrete slabs outside your home, such as in your driveways, paths and patios.
If these outdoor areas are experiencing sinking, it could also indicate deeper issues underground.
The risks outside can vary, but include damage to underground wiring or services, drainage breaks or leaks, and other safety hazards.
Re-levelling your concrete here is key to ensuring a safe, functioning, and aesthetic outdoor space.
What causes sinking floors and slabs?
There are many different causes of subsidence and various contributing factors.
All involve some change in the ground, which, in turn, generates movement of the soil.
As well, different types of ground are more affected by different conditions.
When ground has been affected, building subsidence is common. Foundations or footings are no longer fully supported, sinking due to weak ground.
Soil Types
Moisture levels in the soil affect reactive clays as they expand and contract.
Oversaturated clays lose their strength resulting in footing subsidence. In loosely packed soils, such as sand and silt, the fine particales in the soil can wash away causing the footing to settle.
Tree Roots
Neighbouring trees and shrubs absorb water using their roots causing movement in the soil as it soaks up moisture in the ground.
Footing Systems
Poor foundation design or inadequate compaction of soil during construction results in movement of the structure as it settles.
Excess Water
Burst or cracked water pipes including blocked sewage and rain gutters can oversaturate clay soils or wash fine particles from sand and silt soils and cause footings to subside.
Extreme or Seasonal Weather
Natural disasters such as flooding, drought and earthquakes affect soil moisture levels in particular clay resulting in excessive foundation movement.
Renovation or Construction
Vibration caused by nearby construction activity such as drilling or piling, or heavy road traffic causes soil particles to shift and settle, resulting in ground subsidence.
Sinking Floor FAQs
What are the Signs of a Sinking Floor?
A sinking floor can be a sign of structural issues in your home and should be addressed promptly. Here are some common signs to watch for:
Visible Slope or Unevenness
- The floor appears slanted or noticeably uneven when you walk across it.
- Furniture may tilt or wobble without reason.
Cracks in the Floor or Walls
- Cracks may appear in floorboards, tiles, or the foundation.
- Cracks in walls, particularly near doors and windows, can accompany sinking floors.
Gaps Between Walls and Floors
- Gaps may develop where the floor meets the walls, indicating a shift in the structure.
Bouncing or Sagging Floorboards
- Walking across the floor feels “springy,” bouncy, or soft.
- Floorboards may creak more than usual or sag when pressure is applied.
Doors and Windows Misaligned
- Doors and windows become difficult to open or close properly due to shifting frames.
Water Damage
- Signs of water damage, such as warping, stains, or rot, may indicate a compromised subfloor.
Foundation Issues
- Visible cracks or sinking areas in the foundation can cause the floor above to sink.
Unusual Noises
- Increased creaking, popping, or groaning sounds when walking on the floor.
What are the Common Causes of a Sinking Foundation?
- Poor foundation support or settlement
- Water damage from leaks or flooding
- Rotting or damaged floor joists
- Soil erosion or compaction beneath the foundation
- Inadequate construction or aging materials
Mainmark also provide the following in Australia: wall crack repairs, sinking floor repair, Concrete slab repair, sinking foundation repair, underpinning, ground improvement, re-levelling, subsidence repair, void filling and slab lifting
Projects
Featured Residential Projects
Get a quote
Arrange a site assessment in 3 simple steps:
Step 1
Submit your enquiry using our online form. Include a brief message about the type of foundation issues you are experiencing.
Step 2
Our friendly customer service team will be in touch to schedule a site assessment that suits you.
Step 3
One of the Mainmark experts will visit your home or property, assess the damage, and ascertain the likely cause. They will establish the approach needed, creating a plan specific to the needs of your building and provide you with a detailed quote.
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Mainmark Ground Engineering Pty Ltd
ABN: 51 606 182 503
