Underpinning advice

How much does underpinning cost in Melbourne?

Published 4 September 2026

Underpinning a house in Melbourne typically costs $15,000 to $40,000. Minor jobs stabilising one corner start around $8,000. Complex jobs on deep reactive clay with difficult access run past $60,000.

That range is uselessly wide until you understand what drives it — so here is how the number is actually built, and what you should be reading in a quote.

Underpinning is priced per pier, not per house

Almost every legitimate underpinning quote in Melbourne is built the same way: a count of piers, multiplied by a rate, plus engineering, permits and making good.

The typical pier rate is $1,500 to $3,500 each. Most residential jobs need eight to fifteen piers. Multiply those out and you land squarely in the $15,000–$40,000 band.

What moves a pier from the bottom of that rate to the top:

• Depth to competent ground. This is the single biggest variable. A pier founded at 1.8m costs a fraction of one founded at 4.5m, and on the deep reactive clay of the western and south-eastern corridors, 3–4m is routine.
• Pier type. Mass concrete is cheapest but slowest and needs the most excavation. Bored concrete piers are the common middle ground. Screw piles cost more per pier but are fast, cause less disruption and can be installed in tight access.
• Access. A pier that a small excavator can reach costs meaningfully less than one hand-dug through a 900mm side setback with spoil barrowed out through the house.
• What is in the way. Services, established trees, paving, decks and retaining walls all add either excavation time or reinstatement cost.

The costs that sit outside the pier rate

This is where quotes diverge most, and where the arguments happen later. A complete quote should name each of these explicitly as included or excluded:

Item	Typical cost	Notes
Geotechnical / soil report	$800 – $2,500	Site classification and depth to competent ground. Frequently excluded.
Structural engineering design	$1,500 – $4,000	Pier layout, depth and load design. Required for a permit.
Building permit + inspections	$800 – $2,500	Through a registered building surveyor.
Floor level survey	$300 – $800	Should be free as part of a proper assessment. Ours is.
Crack repair and re-rendering	$1,000 – $5,000	Structural crack stitching, patching, painting.
Plaster and cornice making good	$1,000 – $4,000	Internal damage from the lift. Very commonly excluded.
Reinstating paving, garden, fencing	$500 – $3,000	What gets dug up has to go back.
Drainage rectification	$1,500 – $6,000	Often the actual cause. Skipping it means doing this twice.

Add those up and you can see how a “$22,000” underpin becomes a $31,000 project. None of these items are dishonest — but a quote that omits all of them is not comparable to one that includes them, and comparing the two headline numbers is how people choose the wrong contractor.

What the cheaper alternatives cost

Underpinning is not always the right tool, and the alternatives are genuinely cheaper when they apply:

• Polyurethane resin injection under a slab: $5,000 – $15,000. Suitable where the slab is structurally sound and the problem is voids or loose soil rather than an inadequate footing. Faster, far less disruptive, no excavation. Not a substitute for underpinning where the footing itself is failing — the comparison is set out in resin injection vs underpinning.
• Slab lifting for external concrete: $2,500 – $8,000. Driveways, paths and garage floors, not the house.
• Drainage correction alone: $1,500 – $6,000. More houses than people expect need this and nothing else. If a downpipe has been discharging at the slab edge for eight years, fixing the downpipe and monitoring for a season is a legitimate first step — and a contractor willing to recommend it is telling you something useful about themselves.
• Crack repair with monitoring: $1,000 – $4,000. Where movement has stopped, sealing and monitoring beats underpinning a house that is no longer moving.

Why two quotes for the same house differ by $15,000

Four reasons, in the order we see them:

1. Different pier counts. One engineer designs for twelve piers, another for eight, because they made different assumptions about how far the affected zone extends. Ask each to show you the pier layout drawing.
2. Different depths. If one quote assumes 2m and the other assumes 4m, the difference is enormous — and only a soil report settles which is right.
3. Different inclusions. See the table above. The cheaper quote is often cheaper because it stops at the piers.
4. Different diagnoses. Sometimes one contractor thinks you need underpinning and the other thinks you need a plumber. That is not a pricing difference, and it is worth resolving before you treat them as competing quotes.

What a fixed price should require

No one can price underpinning accurately from a phone call or a few photos. Before a genuine fixed price exists, someone needs to have:

• taken floor levels across the whole house and mapped which way each part has moved
• inspected and mapped the cracking, inside and out
• checked the drainage — downpipes, stormwater, irrigation, and any wet patches
• established the soil classification and depth to competent ground, from a report or local knowledge
• had an engineer design the pier layout

If a number arrives before that work happens, it is an estimate wearing a fixed price’s clothes, and it will move.

The red flags

• A price with no pier count. If the quote does not say how many piers and how deep, there is nothing to hold anyone to.
• “No permit needed.” Underpinning is building work. It needs a permit and an engineer. This should end the conversation.
• A deposit above 10%. Victorian domestic building contracts cap deposits — 10% for work over $20,000, 5% above that threshold in most cases. A demand for 40% up front is a warning about the business, not the job.
• Pressure about “further damage” within days. Foundation movement is measured in seasons. Urgency is a sales technique here far more often than an engineering reality.
• A quote that is half of everyone else’s. Read the inclusions before you read it as a bargain.

What you should do next

Get the level survey done, get the drainage checked, and get the diagnosis right before you get three prices. A cheap underpin of a house that needed a plumber is the worst outcome available, and it is more common than it should be.

Our full cost breakdown covers restumping alongside underpinning and how to compare quotes line by line, and the underpinning service page explains how we assess movement before we quote it.

Common questions

Can I get an accurate underpinning price over the phone?

No, and a firm number offered over the phone should make you cautious rather than pleased. Underpinning is priced per pier, and the pier count and depth cannot be known without floor levels across the house, a look at the cracking, a drainage check and an understanding of the soil and depth to competent ground. What you can reasonably get by phone is a range and an explanation of what would move you within it. A fixed price that arrives before anyone has measured anything is an estimate wearing different clothes, and it will move.

Does home insurance cover underpinning?

Usually not. Most Australian home policies explicitly exclude gradual foundation movement, subsidence and settlement, which is what the majority of underpinning addresses. Where cover can apply is damage arising from a sudden escape of water from a pipe, which many policies do include. If a leaking sewer or water line caused the movement, that is worth pursuing with dated documentation and the plumber's CCTV report. Do not assume either way without reading your own product disclosure statement.

Is it cheaper to underpin the whole house or just the affected part?

Partial underpinning is cheaper and is frequently the correct engineering answer, but it has to be designed rather than simply confined to where the cracks are. Stabilising one section transfers its load to ground that no longer moves seasonally, while the rest of the house continues to ride the cycle — which can create a new differential at the boundary between the two. A competent engineer designs for how the whole structure will behave afterwards. Underpinning only the cracked corner because it is the cheapest quote is how people end up underpinning twice.

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