What does unlevel buildings mean?

Unlevel buildings are the result of weak ground and/or subsidence.

The appearance of internal or external wall cracks, inability to open and close windows and doors, cracked floors and more can all signal an unlevel building. Once a building becomes unlevel, it is crucial to fix it immediately or risk further damage and potential hazards. This requires foundation repair, footing repairs, and house re-levelling.

Mainmark offers state of the art technology to stabilise the ground beneath your home.

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 worldwide.

How much does Foundation Repair cost?

Get a FREE house 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.

How we get your home back to level in as little as a day.

Unlevel homes

Mainmark offers the most advanced technology for house re-levelling and underpinning. We raise and re-level sunken buildings, then add underpinning footings to support the ground underneath to strengthen the house footings. We have successfully raised, re-levelled, and re-supported thousands of homes around the world. We visit your home, assess the damage, and discover the cause. Our experienced engineers and technicians establish the approach needed, creating a plan specific to the needs of your house. As the house is brought back to level, underpinning footings are corrected, sunken floors are raised, and any internal and external wall cracks generally close up too. Most importantly, structural damage is resolved and, with a stable foundation, the future of the house is sound.

Our solutions for concrete re-levelling, footing repairs, and foundation repair under houses are cutting edge and are a more modern alternative to the traditional way of concrete underpinning. Our alternative technologies are likened to keyhole surgery as the as the injection holes are often as small as the size of a five cent coin. These solutions are not just for concrete slab floors. We can raise, re-level and re-support strip footings and raft slabs, plus we can infill slab driveways and paths. We offer a range of technologies for strengthening foundation ground and house footings, and re-levelling homes, such as our proprietary Teretek engineered resin solution. The resins and hardeners mix together in the ground, and expand to compact the adjacent soils and increase their load-bearing capacity. This corrects building subsidence even in weak soils.

We also offer JOG Computer-Controlled Grouting, which is a computerised level correction system. It involves injection of grout, in sequence and rapid succession, via multiple injection ports. This underpinning method creates many localised hydraulic forces, strategically-arranged over large areas, to effectively ‘float’ the structure back to its design level without using traditional piles or hydraulic jacks.

What causes unlevel buildings?

A loss of ground moisture, such as in drought conditions, can cause buildings to subside and become unlevel. The weight of the building causes it to sink, but the nature of soil and clay shrinkage is that the foundation subsidence is never usually uniform. Loss of support varies across the structure, often causing cracks to form. Often, as the soil or clay becomes moist again and expands, some of the damage may be reversed. However, without ground compaction, all wall cracks are prone to reopen with the next extended dry period.

Earthquakes can cause unlevel buildings and soil liquefaction, which makes previously-stable soil behave like a liquid, causing buildings to become extremely unstable. In many cases the damage that caused the building to become unlevel happens over very long periods of time, making it difficult to pinpoint the exact cause. Regardless of the cause, subsidence repair is possible, and unlevel buildings can be re-levelled and re-supported.

Likely causes:

Water flooding the ground

Drought drying out soil

Washaways from broken pipes (such as water, sewer, stormwater drainage)

Poorly compacted fill

Liquid, gas or mineral resources being removed from the ground


Earthquake and seismic activity, often resulting in liquefaction

Tree roots can suck moisture from the ground

Vibrations caused by heavy road traffic or by machinery

Absence of an organised footing system – in very old buildings or in buildings with additions or alterations

Nearby excavation

Heavy loading

Deterioration of retaining walls

How to fix unlevel buildings?

Mainmark specialises in raising, re-levelling, and re-supporting unlevel buildings by treating the foundation subsidence beneath them which, in turn, allows for the foundation slab to return to level. For example, we can inject structural resins into the foundation ground under the building’s footings for foundation repair and footing repairs. The resins expand together chemically, creating pressure. That pressure lifts the building back to its correct level. Then, if there are weak layers in the ground, continuing injection at deeper levels can resolve this by compacting the ground, densifying and strengthening it to increase its bearing capacity for the future.

Alternatively, we can undertake JOG Computer-Controlled Grouting for re-levelling. Extremely successful in subsidence repair, this award winning method was used to re-level the Christchurch Art Gallery after it suffered building subsidence following an earthquake. JOG is a computerised level correction system that involves, in sequence and rapid succession, grout injection via multiple injection ports. This creates multiple localised hydraulic forces, strategically-arranged over large areas, to effectively float a structure back to level. In some soil conditions, Mainmark can increase the bearing capacity of weak strata by as much as 500 per cent.

Mainmark’s concrete slab levelling methods are fast, efficient, and cost effective; they don’t require you to vacate the building while work is being done.

Various product warranties and Building Code requirements apply (please fill out the enquiry form to see which apply in your region or country).

“We were both pretty flat out last week and I was certainly drained after the week of mind spinning building complications, with loads of potential good and bad outcomes.

However I just need to, and want to, shoot off this note to you and the Mainmark team.

I’ve been in sales calling on a wide range of businesses for over 40 years and I’d struggle to recall a business more professional, technical and personable than Mainmark.  An amazing team with J____, D_____, N___, Z__ and the boys from ‘team Ireland’

I was probably a bit of a pain hanging around each day, chirping in with questions, listing to the ‘Brain storming’ sessions, but on each occasion the team helped, answered and explained what was going on which was much appreciated.

Thank you and I’d appreciate if you would pass on my comments to the Mainmark management and the guys that worked on our flats.

Got to say boys, you knocked it out of the park. !!”

Robert, Lane Cove, NSW. September 2020

“Top job by Mainmark”

Loui, Taylors Lakes, VIC. March 2022.

“Was impressed by B____’s honesty in handling my problem with the walls.”

Anna, Langholm, Auckland, NZ. May 2021

“The crew did an excellent job on Saturday. The chimney is straight. It lifted a bit more than I was expecting inside the house but also tilted back to where we wanted it.

Please pass along my thanks to K____ and his team.”

Tom, Metcalfe, QLD. March 2022.

“Just wanted to provide some feedback on the team doing the house lift here last week.

They were courteous and respectful, went about their work with a great deal of professionalism, and were very approachable. As the homeowner looking for a successful outcome their way of working made me very glad to have them on site. G__ in particular did an incredible job leading the team and engaging with me during the day as I had questions or we needed to make decisions about next steps in the process.

Couldn’t recommend the team more highly – please feel free to pass on to whoever is up the chain so they know how very happy I was to have had them here.”

Guido, Island Bay, Wellington, NZ. February 2021

“We just wanted to thank you and the team for the recent work done at our Flaxman Valley home. We are very satisfied with your Teretek underpinning method, and were so pleased with the team that effected the work here. What a lovely professional group of young men they are.”

Alan & Di, Flaxman Valley, SA. February 2021.

“I would like to thank you for the wonderful job you and your employees did at our house. You were in and out within the day and were only too happy to explain the process to us. With your assistance I can now commence on my renovations.”

Glenis, Howard Springs, NT. January 2015

“I would like to take this opportunity to provide positive feedback about one of your Area Managers, P___.

I contacted your Company recently as we feared we may have had some structural and/or slab issues with our residential property in Narre Warren South, VIC.
I was politely advised by one of your Customer Service team (A______), that one of your specialists would be in contact shortly to make an appointment.
I was contacted by P___ shortly thereafter, and an appointment was made for him to inspect our home.

I cannot speak highly enough of P___, and the service he provided.
He was extremely knowledgeable and friendly, and explained everything to my wife and I in terms that were easy for us to understand. He took his time and did not rush, ensuring we understood his explanation, and answered all questions thrown at him. Fortunately for us, we appear not to have any issues that we feared, and P___ alleviated any concerns we had. By the time he was finished, my wife and I felt guilty that this was a “free, no obligation” inspection, as we felt P___ deserved something for his time, effort and patience.

It has been a pleasure dealing with P___, and by extension, your Company. I’m sure you are well aware of what an asset P___ is to your Company, and how extremely well he represents Mainmark.
I will have no hesitation whatsoever in thoroughly recommending P___ and Mainmark to anyone with potential property issues that you may be able to resolve.

I hope this feedback goes some way in appropriately recognising P___’s great service.”

Bruce, Narre Warren South, VIC. June 2021

“A job very well done here. Three more personable employees would be hard to find. They were so professional to deal with. Your company should be celebrating such positive interactions with customers. Overall attention to detail and the clean up are greatly appreciated too. 

Your interactions have been very positive and professional as well. Thanks, in particular for your patience with our tricky access. All was fine in the end.

David, Bowan Park, NSW. May 2019

Benefits of Mainmark’s house levelling methods:

Can be carried out at one or more depths, as deep as 14 metres under the surface

Can increase the bearing capacity of weak strata under structures by up to 500 per cent

Can be used for subsidence repair and to prepare structures that need to support increased loads, e.g. when there is to be an addition to the building itself

We don’t make a mess: there is no concrete dust, water, or any other materials to clean up

There is minimal disruption to your daily life

We don’t cause further damage to the house or landscaping

With simple jobs, residents can stay in the home and may not even need to move furniture

Techniques are non-invasive: we don’t tear up floors or excavate ground

Our methods are fast, completed in a fraction of the time of traditional methods, so we can finish your project in as little as one day

The products and techniques we use have zero negative impact on the environment.

Mainmark building levelling methods used on residential homes: