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A Sign of Subsidence
What is Subsidence and how to fix it?
Subsidence can happen naturally as part of the earth’s constantly shifting crust. It can be exacerbated by issues such as soil compaction, loss of ground moisture, excessive excavation, or erosion. Ground instability causes subsidence and often, the damage can seem to be reversed as the ground shifts back and forth over time.
Using resin injection ground stabilisation, we improve ground compaction. We can then raise and re-level sunken buildings then 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 around the world.
Identifying subsidence
Subsidence is not without warning signs. Some of the most common include:
Internal cracked walls
Wall cracks are common in homes and are often the first sign of foundation subsidence. Inside the house, they appear like steps in the brickwork/blocks or tiles and typically follow mortar or grout lines. The mortar and masonry deteriorates over time due to the movement of the affected wall.
Sinking floors
A concrete floor slab within a home can sink due to weak ground or subsidence. A building can sink at various localised points or can be spread across the entire footprint of the house foundation.
Jammed doors
Doors that don’t open smoothly, have uneven gaps or rub against frames are often a first indication of foundation damage
Exterior cracked walls
Step wall cracks are common in homes and are often the first sign of foundation subsidence. The mortar and masonry deteriorate over time due to the movement of the affected wall. Wall cracks are usually of concern when one side of the wall is higher than the other or cracks are wider than about 5mm.
Sinking & uneven concrete slabs
Sinking and uneven concrete driveways or path slabs can be an indication of unstable ground due to voids beneath the surface. If there is noticeable soil building up around slab joints, the concrete slab can start to crack around the edges as weight is exerted where there is no ground support.
Articulation joints
Usually visible in building extensions where two walls join and in modern buildings at the sides of large window and door openings. The gap is often wider at the top of the joint, exposing the lining.
Video
Our non-invasive technology can raise, re-level and re-support sunken homes and buildings.
What causes subsidence?
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.
How we get your home back to level in as little as a day.
Features & Benefits
Mainmark’s Solutions & Technologies For Subsidence
Fast, Surgical & Accurate
The process is accurate within a few milimteres and completed within hours compared to traditional methods.
Environmentally Inert
No effect to the surrounding soils.
Non-Invasive
Repairs are performed without the need for excavation, extensive road closures or traffic disruption.
Cost-Effective
Compared to traditional methods, our solutions are more cost-effective.
Sinking floors & concrete
Featured Projects
FAQs
What does house subsidence mean?
House subsidence is a serious structural issue that can cause visible damage to a property and compromise its stability. It is typically caused by changes in the ground beneath the building, which might result from natural processes, nearby construction, or underground disturbances. For a detailed article on what it means and what causes refer to https://mainmark.com/what-does-house-subsidence-mean-and-what-causes-it/
We can help with your subsidence issues in the following locations: NSW, Victoria, Queensland, South Australia, Western Australia, Sydney, Melbourne, Brisbane, Perth, Adelaide, Hobart and Newcastle.
What are the first signs of house subsidence?
The first signs of house subsidence often develop gradually and can include noticeable changes in the structure or functionality of your property.
The most common early indicators are cracks in walls, sticking or misaligned doors and windows, uneven or sinking floors, changes to wallpaper or plaster, gaps between extensions and the main building and external signs around the foundation.
How to fix house subsidence?
Fixing house subsidence involves identifying and addressing the root cause of the problem, followed by repairs to stabilise the property and prevent further damage.
How do I tell if my house is sinking?
Identifying whether your house is sinking (a sign of subsidence) requires close observation of structural and functional issues in and around your property.
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
