Since 1989, Mainmark has provided successful ground improvement, level correction, and void filling solutions, addressing subsidence in residential properties.
Learn more
Fast, cost effective & non-invasive subsidence solutions to fix cracked walls and cracked bricks
Fast, clean and non-invasive lifting of sinking floors and slabs
Our solutions are more cost-effective, with minimal disruption to the area
We offer the most advanced house re-levelling and underpinning technology in the market
The world’s most advanced earthquake remediation, liquefaction mitigation and ground-strengthening technologies
Resin Injection Underpinning– the modern alternative to traditional underpinning
Ground improvement modifies a soil’s properties, improving its load bearing capacity or resilience against liquefaction
We re-level buildings that have experienced subsidence, settlement, or other structural issues leading to uneven floors and foundation cracks
We can underpin, raise and re-level sinking foundations
Comprehensive void filling solutions for diverse market sectors, using specialised chemical or cementitious grouts
Our non-invasive and cost-effective solution is a safe way of re-levelling concrete slabs with soil settlement or subsidence problems
Mainmark has delivered ground engineering solutions to commercial businesses and properties for 35 years. Capitalising on this expertise and knowledge, our range of innovative products and advanced solutions provide remediation of assets and structures.
Learn more
State-of-the-art, non-invasive solutions to ensure productivity is maintained
Address a range of underlying issues impacting buildings and infrastructure due to weak or unstable ground
We remediate assets for electricity, gas, waste management and telecommunication providers, as well as water authorities
Our non-invasive approach is essential when treating these significant and sometimes fragile structures
Ground improvement modifies a soil’s properties, improving its load bearing capacity or resilience against liquefaction
We re-level buildings that have experienced subsidence, settlement, or other structural issues leading to uneven floors and foundation cracks
Our non-invasive and cost-effective solution is a safe way of re-levelling concrete slabs with soil settlement or subsidence problems
Comprehensive void filling solutions for diverse market sectors, using specialised chemical or cementitious grouts
Terefil is a unique, specialist flowable fill material that can fill massive pipelines and concrete culverts quickly and cost-effectively
Our innovative technologies offer advanced site-specific solutions for revitalising ageing or damaged buildings, assets and infrastructure.
Learn more
Keeping Australia's roads and bridges operational with minimal disruption
The fast, non-disruptive pavement stabilising solutions for Australia's airports
Re-supporting port terminals and seawalls with minimal disruption to operation whilst prioritising safety
Keeping railways on track with innovative level correction solutions
Ground improvement modifies a soil’s properties, improving its load bearing capacity or resilience against liquefaction
We re-level buildings that have experienced subsidence, settlement, or other structural issues leading to uneven floors and foundation cracks
Our non-invasive and cost-effective solution is a safe way of re-levelling concrete slabs with soil settlement or subsidence problems
Comprehensive void filling solutions for diverse market sectors, using specialised chemical or cementitious grouts
Terefil is a unique, specialist flowable fill material that can fill massive pipelines and concrete culverts quickly and cost-effectively
If you cant find what you’re after please don’t hesitate to contact us.
Please select the global region website you'd like to view.
Submit your enquiry using the online form with a brief description of the issue. A Mainmark expert will be in touch within 24–48 hours (excluding weekends and public holidays).
After clicking Submit, you’ll receive an email with the next steps—please check your inbox and spam folder.
House subsidence occurs when the ground beneath a property sinks or shifts, causing the foundations of the house to move unevenly. This can lead to structural damage to the property.
Subsidence is different from settlement, which happens when a new property naturally compresses into the ground shortly after construction. Subsidence, however, is a more serious issue that requires attention and often repair.
Clay soils: Shrink during dry weather or drought as they lose moisture, causing the ground to sink.
Sandy or loose soils: Can wash away, leaving voids under the foundation.
Peat soils: Compress when they dry out, reducing support.
Trees and shrubs near a property may draw moisture from the soil, particularly in clay-rich areas, causing the ground to shrink.
Extended dry spells can dry out certain soils, leading to shrinkage and subsidence.
Mainmark provides underpinning in, Canberra, Hobart, Townsville NSW, QLD, SA, WA, Tasmania, Victoria plus the major cities of Sydney, Melbourne, Perth, Adelaide, Brisbane, Newcastle
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
If left untreated, subsidence can weaken the structure of a house, leading to extensive (and expensive) repairs. In severe cases, it may even render the property unsafe.
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.
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.
Doors that don’t open smoothly, have uneven gaps or rub against frames are often a first indication of foundation damage
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 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.
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.
Submit your enquiry using our online form. Include a brief message about the type of foundation issues you are experiencing.
Our friendly customer service team will be in touch to schedule a site assessment that suits you.
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.
© 2026 The Mainmark group of companies. ‘Mainmark®’, ‘Terefil®’, ‘Terefirm®’ and ‘Teretek®’ are trademarks of the Mainmark group of companies.
Mainmark Ground Engineering Pty Ltd
ABN: 51 606 182 503
1800 623 312
Australia
