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Our Solutions

Underpinning

Stabilising your home’s foundation is simple with Buildfix’s advanced underpinning solution.

What is underpinning?

Underpinning is a process that strengthens the foundations beneath a house to allow for additional loads and correct subsidence.

Most of the time, the underpinning of a home is a massive undertaking for everyone involved, which can be quite costly for homeowners. Because of this, it’s particularly important to understand what’s causing your home to subside, as well as the various underpinning methods available and the advantages and disadvantages they can bring.

Why is underpinning essential for a sinking home?

When a home suffers from subsidence, an immense amount of force is being exerted onto the structure. This force strains the foundations, floor, walls, ceiling and even the roof.

If sinking isn’t stopped, foundational and structural issues like wall cracks will multiply. This escalates repair costs, putting a massive hole in your budget. Underpinning is essential in stopping this, preventing your home from sinking, avoiding further damage and saving you money.

The traditional ways of underpinning a home

Mass concrete underpinning

Mass concrete underpinning, also known as traditional underpinning, is one of the most common types of underpinning around. It involves excavating multiple holes underneath a home to construct box shaped piers that lend support to the structure. Although being commonly used, concrete underpinning is also well-known for its high cost and inconvenience, making it a less than ideal solution for most homeowners.

Steel pile underpinning

Steel pile underpinning is an option for subsiding homes built on a hillside. It involves driving steel piles into the ground with specialist hydraulic machines. These pipes are then fixed with brackets that are attached to structural walls and footings. This method is effective in certain situations and should be considered in areas prone to landslips. However, it requires heavy machinery, which presents challenges to access in residential areas.

Cement grout underpinning

Cement grout underpinning is a form of preventative maintenance for buildings and structures at risk of subsiding. This type of underpinning is performed by pumping a special concrete mix, or non-shrink cement grout, underneath the structure, filling in any large holes and voids. While effective in theory, this method depends on easy access to the voids beneath homes. This is often a significant barrier to use for homeowners, making it a generally impractical option.

Our advanced underpinning solution – GeoPoly™

GeoPoly™ is a game-changer for homeowners, offering a progressive, non-invasive approach to subsidence—it’s like keyhole surgery for your home’s foundations.

Unlike traditional underpinning, which requires disruptive and costly construction, GeoPoly™ works by being injected through coin-sized holes directly into the ground beneath your home.

GeoPoly™ meticulously lifts and stabilises your foundations, effectively solving deep-rooted subsidence issues, ensuring a long-lasting, cost-effective solution with minimal disruption.

Our advanced underpinning solution – GeoPoly™

GeoPoly™ is a game-changer for homeowners, offering a progressive, non-invasive approach to subsidence—it’s like keyhole surgery for your home’s foundations.

Unlike traditional underpinning, which requires disruptive and costly construction, GeoPoly™ works by being injected through coin-sized holes directly into the ground beneath your home.

GeoPoly™ meticulously lifts and stabilises your foundations, effectively solving deep-rooted subsidence issues, ensuring a long-lasting, cost-effective solution with minimal disruption.

The advantages of our underpinning solution

Lifts foundations

If your foundations are sinking, GeoPoly™ can lift them back. Cracks may even close, making your home look better instantly.

Minimal Disruption

GeoPoly™ is non-invasive and is injected through small holes from the surface. No excavations, and zero mess.

Immediate Results

GeoPoly™ gets to work fast, meaning subsidence can be fixed in no time. Most jobs are completed in just one day.

20-Year Warranty

You’ll get complete peace of mind. We guarantee your subsidence won’t return, or we return at no cost to you.

Need an underpinning solution? Book a FREE structural assessment today

Need an underpinning solution?
Book a FREE structural assessment today

Watch: GeoPoly™ fixes a sunken home in minutes!

Real feedback from real homeowners

Don’t just take our work for it! Hear what our customers say.

Read genuine reviews on Google and Trustpilot to learn about the real experiences others have had with our services.

Reasons why you should choose Buildfix

FREE structural assessment and honest advice

Buildfix structural engineers or consultants come to your home at no cost. Our assessments are thorough, uncovering your home’s issues and the best solutions.

UNLIMITED GeoPoly™️ for your job

After we’ve completed your quote, we don’t change it. We don’t add extra costs at the end. With us, there are no tricks, no games and zero surprises.

Permanent repair guaranteed

Using our advanced underpinning technology, GeoPoly™️, we can lift your foundations and solve your subsidence permanently. Everything we do is guaranteed to last.

Experience - thousands of projects completed

With well over 10000 projects completed, you'll get the most experienced and committed teams around. Your home is in expert hands with our proven track record.

Best price promise

With our leading techniques and technology, we work more accurately and more efficiently than anyone else. We promise the best price* on advanced underpinning technology, if not we'll beat lower offers by 5%.

*Must be like-for-like, covering the same area with unlimited GeoPoly™️, or similar material.

We cover locations throughout Australia

Our teams are ready to go where you live. Whether it be in Brisbane, Sydney, Canberra, Melbourne, Perth or anywhere else in between**, we’ll come out and do the job for you.

**Excludes some remote locations.

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Frequently Asked Questions

Can underpinning repair wall cracks?
GeoPoly™ effectively stabilises the soil under your foundation, preventing further subsidence. It can even lift the foundations of your home, enabling cracks to close and restoring the functionality of doors and windows. However, it’s important to note that underpinning alone might not address all structural issues in your home. To complement this, we also provide specialised solutions for wall crack repair and undertake cosmetic repairs, such as plastering and brick pointing, to ensure a comprehensive approach to your home’s structural issues.
Mostly, yes. The majority of our underpinning projects are completed within a day. However, the duration varies depending on the complexity of the repair, the foundation size and the ground conditions.
Definitely not. Buildfix primarily works externally, allowing you to continue daily life inside your home without disruption. Occasionally we might require indoor access based on the project’s needs, but we’ll always work around you.
Buildfix has successfully assessed and completed tens of thousands of projects across Australia over the past decade. This mostly includes residential projects but covers commercial and strata buildings as well.
Minimal disruption is one of our aims. We inject our GeoPoly™ resin through small holes in the ground, akin to ‘keyhole surgery,’ minimising excavation and mess. You can continue with your regular home life while the work is being carried out.
Underpinning is the process of strengthening the foundation of an existing building or structure. It is typically necessary when the original foundation is no longer able to support the building due to soil issues or other changes in the ground conditions.
Signs that your property might require underpinning include cracks in walls, especially around doors and windows, doors or windows that stick or won’t close properly, and uneven floors.

Absolutely. We proudly offer an industry-leading, transferable 20-year warranty on workmanship, as well as a 50-year product warranty. This extensive coverage ensures your peace of mind for years to come and adds value to your property, even if you decide to sell it in the future.

GeoPoly™ is a closed-cell geopolymer resin, and belongs to the polyurethane family.

100%. GeoPoly™ is exclusively made by our in-house chemical engineers, at our dedicated manufacturing facility, adhering to our proprietary formulation. This commitment guarantees that you receive the highest-grade material, proudly Australian-made and unrivaled in the market.
Yes, our GeoPoly™ resin is environmentally safe and poses no harm to the surroundings. It is classed as non-hazardous.
When it comes to performing work on the day, our skilled technicians will handle the repairs on your property, directed by our team of structural engineers and builders. All Buildfix technicians, engineers and builders are full-time employees, not subcontractors, ensuring you always receive highly experienced and committed experts
Yes, underpinning is designed to be a long-term solution to foundation problems. The GeoPoly™ method, for instance, is engineered to create a stable base for the structure, addressing the underlying issues causing foundation failure.
Underpinning, especially with techniques like GeoPoly™, is designed to be minimally invasive, reducing the risk of damage to the property’s landscape or structure. However, the extent of any potential impact depends on the specific circumstances and should be discussed with the service provider.
Traditional underpinning often involves extensive excavation and concrete reinforcement. GeoPoly™ is an advanced, non-invasive technique that stabilises foundations by injecting a geopolymer resin into the ground, which then expands and hardens to support the structure.

#1 Underpinning
Top-Rated in Australia!

We’re happy to take a look at your home for FREE.

#1 Underpinning
Top-Rated in Australia!

We’re happy to take a look at your home for FREE.