How much does foundation repair cost?

Most foundation repairs range from $4,000 to $16,000, depending on the extent of the damage and the size of your property.

How long does the repair take?

Most foundation repairs are completed in just 1-2 days using our GeoPoly™ resin injection method.

What is GeoPoly™ resin injection?

GeoPoly™ is a high-strength expanding resin that we inject beneath your foundation. As it expands, it fills voids, compacts loose soil, and lifts your foundation back to level.

Will you need to dig up my yard?

No! We drill small holes (about 16mm diameter) through your slab or beside your footings, inject the resin, and patch the holes. No excavation required.

What does the 20-year warranty cover?

Our 20-year structural warranty covers the repair work we perform. If any issues arise with the repaired area due to workmanship or materials, we'll fix it at no additional cost.

Is the assessment really free?

Yes, 100% free with no obligation. Our structural engineer will inspect your property, explain the issues, and provide recommendations.

How do I know if my home has subsidence?

The most common signs are cracks appearing or widening in walls, doors and windows that stick or won’t close properly, uneven or sloping floors, and gaps between walls and ceilings. If you’ve noticed any of these — especially if they’re getting worse — it’s worth having a structural engineer take a look. Our assessment is free and no-obligation.

What causes subsidence?

The most common cause in Australia is reactive clay soil — ground that swells when wet and shrinks when dry, constantly moving your foundations with it. Other causes include tree root intrusion, poor drainage, leaking pipes, and drought conditions. Our engineers identify the exact cause during the free assessment, so the solution targets the root problem.

How does GeoPoly™ differ from traditional underpinning?

Traditional underpinning means excavating around your home, pouring mass concrete into trenches, and weeks of your property being a building site — often costing tens of thousands. GeoPoly™ resin injection works through small, coin-sized holes — no excavation, no trenches, no heavy machinery. Most jobs are done in 1–2 days at a fraction of the cost, and the result is guaranteed for 20 years.

Will my home be re-levelled?

Yes. Real-time laser monitoring and digital sensors control every millimetre of the lift. The GeoPoly™ resin is injected gradually, lifting and re-levelling your foundation with precision. You’ll see the results before the team leaves.

Is the job done in just 1–2 days?

Most residential subsidence repairs are completed in 1–2 days. The exact timeframe depends on the size of the affected area and the depth of injection required — your engineer will confirm this during the free assessment.

How much does subsidence repair cost?

Every property is different, so we quote individually after the free structural assessment. The price we quote is the price you pay — fixed, with no hidden costs. GeoPoly™ is typically a fraction of the cost of traditional underpinning.

Do I need council approval?

In most cases, no. GeoPoly™ injection is classified as maintenance work and doesn’t require council permits. If your property does require approval for any reason, your engineer will let you know during the assessment.

Can I stay in my home during the repair?

Yes. GeoPoly™ injection is non-invasive — no excavation, no heavy machinery, no mess. Most homeowners stay in their home throughout the entire process.

Is the 20-year warranty transferable if I sell my home?

Yes. Our 20-year warranty is attached to the property, not the owner. If you sell, the warranty transfers to the new owner automatically — giving buyers extra confidence.

What if the subsidence returns after the repair?

It’s covered by your 20-year warranty. If the subsidence returns in the repaired area, we come back and make it right — at no additional cost.

Will the cracks in my walls close after foundation repair?

Many wall cracks close on their own as the foundation is lifted back to level. Any remaining cracks can be repaired cosmetically, or structurally using our HelicalBar™ wall crack repair if needed. Your engineer will advise on this during the assessment.

Worried About Your Home’s Foundations?

Find the cause, stabilise your foundations, and reverse subsidence permanently — guaranteed for 20 years.

Free quote · 1–2 day repair · 20-year warranty
Structural Engineers · Licensed Builders · Skilled Technicians

Worried About Your Home’s Foundations?

Find the cause, stabilise your foundations, and reverse subsidence permanently — guaranteed for 20 years.

Free structural assessment with a fixed-price quote
No excavation — most foundations stabilised in just 1–2 days
Backed by a 20-year warranty

Qualified Engineers · Licensed Builders

15,000+Homes Repaired

20-YearStructural Warranty

1–2 DaysMost Repairs

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It's Brilliantly Simple.

Non-Invasive. Precision-Controlled. Guaranteed.

No Digging. No Mess. No Excavation — Ever.

Sticking doors. Cracks in the walls. Floors that slope. These are signs your foundation is moving — and no amount of patching will fix what's happening underneath. The only way to stop it is to stabilise and re-level the foundation itself.

If you've been quoted for traditional underpinning — excavation around your home, mass concrete poured into trenches, weeks of disruption — there's a smarter way. It costs less, it's done faster, and your home doesn't become a building site.

GeoPoly™ resin injection is like keyhole surgery for your foundation. Small, coin-sized holes are drilled around the problem areas, then engineered resin is injected at precise depths beneath your home. The resin expands, fills voids and weak spots, and lifts your foundation back to level. That's it. No trenches, no concrete, no heavy machinery — just a permanent fix through holes you could cover with a 20-cent piece.

The whole job typically takes one to two days — at a fraction of the cost of traditional underpinning. When we're done, we patch the drill holes, and your home looks exactly as it did before we arrived. Except now it's level, stable, and guaranteed for 20 years.

Want to know exactly what your home needs? Get in touch for a free, no-obligation structural assessment.

What to expect

Here’s how we stabilise and re-level your home’s foundations, from first visit to warranty.

Buildfix structural engineer assessing foundation subsidence with laser level equipment

Step 1

Free Structural Assessment

One of our qualified engineers assesses the subsidence, identifies the root cause, and designs a tailored solution. Repair details — with photos, markings, and measurements — are 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 statement

Step 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™ injection

Step 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 foundations

Step 4

Inject, Lift, and Level

GeoPoly™ resin is injected through the access points. The resin 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 precise, controlled, and exactly right.

Patched drill holes after GeoPoly™ subsidence repair with clean site

Step 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.

Step 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. That’s your peace of mind, in writing.

See the difference

Actual GeoPoly™ projects where subsidence is permanently reversed.

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 a GeoPoly™ subsidence repair.

GeoPoly™ resin is injected beneath your foundations and monitored in real time with laser levelling equipment. Every millimetre of the lift is controlled — so your home is brought back to level with precision, not guesswork.

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

Real homes. Real results

See how we’ve helped homeowners fix their foundation subsidence.

Why choose Buildfix?

Buildfix brings qualified engineers, licensed builders, skilled trades, and the manufacturer together under one roof. One team accountable for every step — from assessment to final sign-off. For nearly 15 years, we've 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.

Here’s why homeowners choose us

20-year warranty: Every repair is backed by a 20-year warranty — transferable if you sell your home.

Under one roof: We assess, design, repair, and manufacture — no need to deal with multiple contractors, because we handle it start to finish.

Fixed pricing, honest advice: No surprises, no tricks — just one fixed price from the start that never changes.

Non-invasive technology: Every method we use is non-invasive — less mess, less stress, and most repairs done in 1 to 2 days.

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Questions?

Our team is here to answer any questions you may have Monday – Friday 8am to 4pm AEST. Give us a call on 1300 854 115.

Worried About Your Home’s Foundations?

Worried About Your Home’s Foundations?

Don't take our word for it

It's Brilliantly Simple.