Buildfix
GeoPoly™ resin underpinning lifting and stabilising foundations on a Buildfix homeowner job

Underpinning

Underpinning your home isn't what it used to be.

GeoPoly™ resin lifts and stabilises your foundation through coin-sized holes. And best of all, it's a fraction of the cost of concrete underpinning.

  • Free assessment · 1–2 day repair · 20-year warranty
  • Structural Engineers · Licensed Builders · Skilled Technicians
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Same outcome. Without the dig. But with lift.

Engineered Resin. Laser-Guided. Guaranteed.

Lift. Stabilise. Done in a Day or Two.

For decades, concrete underpinning was the only solution. The mere mention of the word would send a homeowner's head into a spin. The costs, the timelines, the nightmare stories — it became one of the most feared words in home repair. And for good reason. In most states, underpinning means a building permit. Engineers. Certifiers. The list goes on.

But once you understand what's actually happening underneath, it gets simpler. The ground below your home can't hold the weight like it used to. A leaking pipe, a downpipe draining the wrong way, reactive clay drying out and pulling away, tree roots hunting moisture and aerating the soil — any of these can hollow out the ground beneath your footings. The soil weakens. The home sinks into the gap.

The fix should be straightforward — fill the gaps with something tougher than sand. That's what the resin does. But GeoPoly™ resin doesn't just fill the gaps. It expands. Injected as a liquid 2+ metres beneath your footings, it travels through every void, then expands and compresses the loose soil around it. Once there's nowhere left to go, it cures — and that expansion has to go somewhere.

For a house that's sunk, it goes up. Cracks start closing. Floors return to level. The damage reverses. Lasers track every millimetre of movement in real time, so the lift is controlled — not estimated. Foundation stable. Home level. Fixed at the root.

What used to be invasive and expensive — weeks of disruption, trenches through your garden, mass concrete under your home — is now done in a day or two. Backed by a 20-year warranty.

Want a straight answer from the people who make GeoPoly™ and inject it? That's exactly what the free assessment is for. Your engineer explains what's moved beneath your home and which method actually fits — resin, concrete, or something simpler.

What to expect

Here’s how we underpin your home’s foundations, from first visit to warranty.

Buildfix structural engineer assessing foundation subsidence with laser level equipmentStep 1

Free Structural Assessment

A structural engineer inspects your foundation, identifies the cause of the movement, and designs the repair. The repair detail — photos, markings, and measurements — is created on-site using our mobile software, and the price can usually be explained there and then. So you know exactly where you stand.

Buildfix quote package showing structural repair detail, quote cover page, and repair method statementStep 2

Get Quote and Book

You receive a complete quote package including detailed drawings, repair method statements, and a fixed-price quote — so you’ll know exactly what it’s going to cost. When you’re ready, book through our online portal (takes about 5 minutes) and we’ll organise suitable dates for the work.

Buildfix technician drilling small coin-sized access holes for GeoPoly™ injectionStep 3

Drill for Access

Small, coin-sized holes are drilled at precise intervals around the problem areas. These allow our injection pipes to reach the exact depths needed beneath your foundation.

Buildfix technicians injecting GeoPoly™ resin beneath foundationsStep 4

Inject, Lift, and Level

GeoPoly™ resin is injected through the access points. It expands to fill voids and weak spots, then lifts and re-levels your foundation. Laser levelling equipment and digital sensors monitor every millimetre of movement in real time — so the lift is controlled, not estimated.

Patched drill holes after GeoPoly™ subsidence repair with clean siteStep 5

Patch and Clean Up

Once the foundation is stabilised and level, we patch the drill holes and clean up. Your home looks exactly as it did before we arrived — except now it’s on solid ground.

Buildfix 20-year warranty badgeStep 6

Receive Your Warranty

A few days after sign-off, you’ll receive your Completion Package — a full report covering the work carried out, materials used, and images from the process. It includes your invoice with links to pay through our portal, and your 20-year warranty documentation. The work covered, in writing.

See GeoPoly™ resin underpinning on real homes.

Real GeoPoly™ projects — foundations lifted and stabilised, controlled to the millimetre.

Press the image for a closer look.

Brick wall subsidence crack before and after GeoPoly repair
Foundation subsidence before and after re-levelling
Subsidence crack in render before and after repair
Sunken foundation before and after GeoPoly injection
Subsidence damage to brickwork before and after repair
Foundation settlement before and after re-levelling
Brick wall separation from subsidence before and after repair
Subsidence crack repair before and after
Foundation subsidence before and after stabilisation
Brick wall subsidence before and after GeoPoly repair

Instant results.
Guaranteed to last.

The benefits of GeoPoly™ resin underpinning.

GeoPoly™ resin is injected beneath your footings and monitored in real time with laser levelling equipment. Every millimetre of the lift is controlled — the same precision approach used to re-level CSIRO’s own research buildings to within 2mm tolerance.

GeoPoly resin injection beneath brick house with laser levelling equipment monitoring precision

Ready to get underpinning?

Our engineer will guide you through. Our technicians will lift it.

Structural Engineers · Licensed Builders · Skilled Technicians

Real homes. Real results

See how we’ve helped homeowners stabilise their foundations.

Why choose Buildfix?

Buildfix brings structural engineers, licensed builders, skilled technicians, and the manufacturer together under one roof. For nearly 15 years, Buildfix has been delivering non-invasive structural repairs — saving homeowners the hassle and costs of traditional methods. What used to take weeks now takes just 1 to 2 days.

Why homeowners choose Buildfix:

Non-invasive technology. No trenches dug. No concrete piers. No weeks on a building site. You can stay home while the work happens.
Guaranteed. Your repair is backed by a 20-year warranty. If the foundation moves again, we come back at no cost to you.
One team, diagnosis to repair. Buildfix engineers assess your home and oversee the repair. Buildfix technicians carry it out.
Save thousands — best pricing. All quotes fixed-price. No hidden charges. No surprise costs. If your job goes over, it's on us.

Watch Video

Learn more about Buildfix and how we underpin and stabilise foundations across Australia.

Structural Engineers · Licensed Builders · Skilled Technicians

All of the Buildfix team have been easy to communicate with. Everyone was punctual and communicated arrival times well ahead of arrival.

Scott HolmesMelbourne, VIC

Questions?

Our team is here to answer any questions you may have Monday – Friday 8am to 5pm AEST. Give us a call on 1300 854 115.

Buildfix structural engineer with client discussing foundation repair

Is your home needing a lift? Easy.

Cause identified, levels measured, and you'll know exactly what method fits — and what it'll cost. No charge.

Structural Engineers · Licensed Builders · Skilled Technicians

Experts in Structural Repair

Non-Invasive. Permanent. Guaranteed.

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