Second opinion
Underpinning in Canberra: independent assessment and second opinion
Firms that sell underpinning or resin injection often assess for free, because they sell the fix. We don't sell any repair. Send us their quote, your photos and any report, and we'll tell you whether the work matches the problem.
- From $390 + GST ($429 inc GST) to check a quote, no visit needed
- Fixed quote in under 20 minutes on average, during business hours
- No repair to sell we don't carry out or recommend repairs
Prefer to talk? Call 02 6189 9876
Or email info@canberrastructuralengineers.com.au
Monday to Friday, 8:00am to 5:00pm
- Engineering onlyWe never sell the repair or the build.
- From $390 + GST($429 inc GST), confirmed before we start.
- Fixed quote in under 20 minutes on averageDuring business hours, Monday to Friday.
- Canberra and the Queanbeyan sideEvery district, plus Queanbeyan, Jerrabomberra and Googong.
In short
An underpinning second opinion in Canberra costs from $390 + GST ($429 inc GST). An engineer reviews the contractor's quote, your photos and any report, then advises whether the cause has been found and the scope fits. Underpinning usually needs building approval; your certifier confirms. An on-site report is from $1,090 + GST ($1,199 inc GST), at the same prices across Canberra and Queanbeyan.
- Second opinion
- From $390 + GST ($429 inc GST), no visit
- On-site report
- From $1,090 + GST ($1,199 inc GST)
- We check
- The cause, leaks and drainage, active movement, the scope
- Approval
- Usually needs building approval; your certifier confirms
- Quote
- Fixed, in under 20 minutes on average, during business hours
- Independent
- No repair to sell and no repairer to recommend
Do you actually need underpinning?
Sometimes. But underpinning supports footings; it doesn't fix a leak, a thirsty tree or poor drainage. The cause has to be found first.
Underpinning means extending or supporting a footing down to firmer ground. The common methods are mass concrete poured under the footing, steel screw piles or piers tied to it, and resin injected into the soil beneath it.
It can be the right answer when footings keep moving after the cause has been dealt with, or when the cause can't be removed.
Cracking can also come from things underpinning won't fix: a leaking pipe, a downpipe emptying against the wall, a tree drawing water from the clay, or seasonal movement a house can live with. Underpin without fixing those and the movement can carry on around the new work.
If you don't yet know why the house is moving, start with a crack and footing movement report. Our guide to cracks in walls in Canberra explains which cracks point to movement.
Three common underpinning methods, side by side
- 1 · Mass concrete: concrete is cast in short sections under the footing, down to firmer ground.
- 2 · Screw piles or piers: steel piles are driven or screwed to a firmer layer and tied to the footing with brackets or a new beam.
- 3 · Resin injection: expanding resin is injected into the soil under the footing to fill voids, densify it and sometimes lift the footing.
What does a second opinion check?
Four questions. If the quote and its report can't answer them, it's too early to sign.
Has the cause been found?
The quote should say why the house is moving: clay, water, a tree or fill. Without a cause, the scope can't be checked against anything.
Have leaks and drainage been fixed first?
Water under a footing keeps the clay moving. Leaks and drainage faults should be found and fixed before anyone sizes a repair.
Is the movement still active?
Cracks that have stopped growing may need patching, not new footings. Watching them through a wet season and a dry one shows the difference.
Does the scope fit the soil and the footing?
How many footings, how deep and which method. In Canberra the depth to firm ground can change across one house.
What to send us
- The contractor's quote and any report or assessment that came with it
- Photos of the cracks, close up and from further back
- When you first noticed them, and whether they've changed
Add up to 5 files with the form at the top of the page.
What you get back
Written advice on the quote: whether the cause has been found, what should happen before any repair, and whether the proposed scope fits what the photos and report show. If we can't answer that without seeing the house, we say so.
Why get an independent opinion on an underpinning quote?
Because the free assessment usually comes from the business that sells the repair.
Firms that sell underpinning or resin injection often assess for free, because the assessment leads to the sale. That doesn't make their advice wrong. It does mean nobody independent has checked it before you pay a deposit.
We're engineers only. We don't sell, carry out or recommend repairs, so our advice is the same whether the answer is a full underpinning scheme, a plumber or nothing at all.
Independent second opinion
- Paid for by you, so it answers your questions
- Starts with the cause, then the scope
- No method or product to sell
Free assessment from a repair seller
- Free because it leads to a sale
- Proposes the method that firm sells
- Scope and price come from the same business
Desktop second opinion or an on-site report?
Start with the desktop review if you have a quote and photos. Choose the on-site report if nobody has diagnosed the cause yet.
| Option | What you get, and when it fits | From, ex GST | Inc GST |
|---|---|---|---|
| Underpinning second opinion | We review the quote, photos and any report you send and give written advice. No site visit. Fits when you already have a quote and want it checked before you sign. | $390 + GST | $429 |
| Crack and footing movement report | An engineer visits, inspects the cracks and the house, and gives a written report with the findings, the likely cause and what to do next. Fits when there's no report yet, or the quote's diagnosis doesn't hold up. | $1,090 + GST | $1,199 |
From prices for a typical house, confirmed in your fixed quote. For a check of the whole house, see our structural inspection and report, or all our prices.
Why does the depth to firm ground vary so much in Canberra?
Because Canberra's rock is often deeply and unevenly weathered. Rock can be near the surface on one part of a block and metres down on another.
In Tuggeranong, a 1976 Bureau of Mineral Resources study found weathering generally less than 15 m deep but irregular, so excavation conditions vary from place to place. Under the inner north and most of Gungahlin, deeply weathered zones are common, generally no deeper than 30 m.
That matters for underpinning. A scope that assumes the same depth under every corner of the house deserves a question, and so does one with no investigation behind it. Footing design starts from your block's own ground: see footings, slabs and site classification.
Does underpinning need building approval in the ACT?
Usually, yes. Underpinning alters the footings, so it usually needs building approval; your certifier confirms.
Building approval comes from a licensed certifier, also called a building surveyor, that you appoint. It doesn't come from the contractor, and it isn't something we give.
Before you sign, ask the contractor who will arrange building approval and what engineering the certifier will need.
The $12,000 line
Part 6 of the ACT Building Act, which covers statutory warranties and residential building insurance, applies to residential work costing $12,000 or more. Structural elements then carry a 6-year warranty from completion. Work under $12,000, and owner-builder work, falls outside it.
What happens next?
Three steps, and you know the price before anything is booked.
Send the quote and photos
Use the form at the top of the page, or email info@canberrastructuralengineers.com.au. Up to 5 files.
Get a fixed quote
We reply with a fixed quote in under 20 minutes on average, during business hours. If a desktop review can't answer it, we say so.
Your second opinion
We review what you sent and give written advice on the cause, what should come first and whether the scope fits.
Often needed alongside a second opinion
Every service is quoted at a fixed price before we start. Send photos or plans and we reply in under 20 minutes on average, during business hours.
Cracks & footing movement
Stepped cracks, sticking doors, gaps at the cornice. An engineer finds the cause and tells you whether it matters.
$1,090 + GST($1,199 inc GST) See the service
Footings, slabs & site classification
Site classification and footing or slab design for new homes, rebuilds, granny flats and extensions, with the soil test at cost.
$1,290 + GST($1,419 inc GST) See the service
How much does underpinning cost in Canberra?
What underpinning jobs cost in Canberra according to published figures, what drives the price, and when fixing the cause means you don't need underpinning at all.
Read the guideUnderpinning questions
Something else on your mind? Call 02 6189 9876, email info@canberrastructuralengineers.com.au or send photos for a fixed quote.
Do I need a structural engineer for foundation repair?
It's worth having one before you sign. An independent engineer checks the cause and whether the proposed repair fits it. Underpinning usually needs building approval too; your certifier confirms.
How much does underpinning cost in Canberra?
It depends on the method, how many footings and how deep firm ground is. We don't sell or price underpinning work. Our guide to underpinning costs in Canberra sets out what drives the price.
Is resin injection better than underpinning?
Neither is better in general. The right method depends on the soil, the footing and the cause of movement, so the diagnosis has to come first. A second opinion checks whether the proposed method fits your house.
Is underpinning work covered by a statutory warranty?
If it's residential work costing $12,000 or more, the Building Act's warranty rules apply. Structural elements carry a 6-year statutory warranty from completion. Work under $12,000 and owner-builder work fall outside those rules.
Can you recommend an underpinning company?
No. We don't recommend repairers or builders. You take our advice to whoever you choose.