What's Included
A structural repair quote covers assessment of the damage or deterioration, removal and replacement of affected structural members (stumps, bearers, joists), re-levelling where needed, and any temporary support (jacking, propping) during the work. All structural timber framing must comply with AS 1684 Residential Timber-Framed Construction, a four-part standard that provides span tables for bearers, joists, lintels, and rafters graded by timber stress grade (F7, F17, MGP10, MGP12) and loading conditions. Where stumps or footings are being replaced, the footing design must comply with AS 2870 Residential Slabs and Footings, which classifies sites from A (non-reactive) through M, H1, H2, to E (extremely reactive, over 75mm ground movement).
An engineer's assessment or design is typically required and may be included in the builder's quote or charged separately. Engineering fees range from $500 for a straightforward site inspection through to $3,000+ for a full structural design with beam specifications and footing details. Labour is the dominant cost component for structural work because of the physical difficulty, temporary propping requirements, and staged inspection processes.
Structural Timber and Material Comparison
Understanding the materials your builder specifies helps you evaluate quotes and know what you are paying for.
| Material | Typical Cost | Best For | Notes |
|---|---|---|---|
| Concrete stumps (pre-cast) | $400–$700 per stump installed | Standard restumping on stable soils | Traditional option. Requires excavation and 3–7 day cure time. |
| Steel screw piles | $500–$1,000 per stump installed | Reactive clay soils, tight-access subfloors | Mechanically driven, no excavation needed. Same-day load bearing. Better on reactive sites (Melbourne west, Adelaide north/south). |
| Galvanised steel posts | $35–$62 per post (supply only) | High-set Queenslanders, replacement stumps | Common in Brisbane. Adjustable models available from brands like LevelMaster and StumpRite (BMSA). Bolted to concrete pads, fully above ground. |
| Hardwood bearers/joists (F17) | $20–$50 per lineal metre (supply) | Replacing rotten subfloor framing | Spotted gum and ironbark are the traditional structural hardwoods. Naturally durable but heavy to handle in confined subfloors. |
| Treated pine framing (H3/H4) | $8–$20 per lineal metre (supply) | Budget bearer/joist replacement | H3 for above-ground use, H4 for in-ground or near-ground contact. Lighter to work with than hardwood. |
| LVL beams (engineered) | $15–$40 per lineal metre (supply, varies by depth) | Lintels, long-span bearers, load-bearing wall replacements | Wesbeam e-beam (E13/E14 grades) is the main Australian-made product. Hyne and Carter Holt Harvey (Futura, Hyspan) also supply the Australian market. Consistent strength, no natural defects. |
| Steel beams (UB/PFC sections) | $200–$500 per lineal metre (supply) | Load-bearing wall removal, heavy structural support | Engineer-specified. Requires crane or multiple workers to position. Installed cost including fabrication, primer, and labour runs $3,000–$5,000 per tonne. |
When You Need Structural Carpentry
Not every crack or squeak means structural failure, but some signs warrant a professional inspection sooner rather than later:
- Bouncy or springy floors when walking, particularly in the centre of rooms, suggest bearers or joists are undersized, overloaded, or deteriorated.
- Floors sloping toward one side or corner of the house indicate differential stump settlement, where some stumps have moved or deteriorated more than others.
- Doors and windows that stick or will not close when they previously worked fine point to the frame shifting as the subfloor moves.
- Visible cracks in plaster walls, particularly above doorframes and at wall-ceiling junctions, often track back to foundation movement.
- Gaps between skirting boards and floors that you can see daylight through are a sign that the floor frame has dropped away from the walls.
- Visible rot, termite damage, or crumbling material under the house, on stumps, or on bearers and joists when you inspect the subfloor.
An engineer or experienced builder can assess whether the issue is cosmetic (settlement that has stabilised), active (ongoing movement), or structural (requiring repair). A structural inspection report typically costs $490–$1,000 for a residential property.
What Affects the Cost
- Number of stumps. A partial restump replacing 10–15 failed stumps costs a fraction of a full-house restump covering 40–80 stumps. At $400–$1,000 per stump installed (depending on material and access), the stump count alone can swing the total by tens of thousands.
- Stump material. Concrete stumps ($400–$700 installed) are the traditional replacement. Steel screw piles ($500–$1,000 installed) cost more per unit but install faster and perform better in reactive clay soils because they anchor past the reactive zone. Galvanised steel adjustable posts are popular in Queensland for high-set homes.
- Crawl space access. Subfloors with 500mm+ clearance allow workers to move around efficiently. At 300mm or less, every task takes significantly longer. Some homes have sections with almost no access, requiring floorboard removal from above.
- Extent of timber damage. Localised rot in one or two bearers ($500–$1,000 per bearer replaced) is a contained repair. Widespread damage from termites or prolonged moisture exposure can mean replacing the entire subfloor frame, with hardwood joists at $20–$50 per lineal metre for materials alone.
- Engineering requirements. A structural inspection ($490–$1,000) is the starting point. A full engineering design with beam calculations, footing specifications, and bracing requirements for a load-bearing wall removal can run $1,500–$3,000+.
- Asbestos risk. Pre-1990 homes may have asbestos sheeting in subfloor areas, behind cladding, or as part of the flooring system. Licensed asbestos removal is required before structural work can proceed, typically adding $1,500–$5,000 depending on the extent.
- Soil conditions. Reactive clay soils (common in Melbourne's west, Adelaide's north and south, and parts of Brisbane) cause stump movement over time. Sites classified H1 or above under AS 2870 may require deeper footings, longer screw piles, or engineered footing designs.
Replacing a handful of failed stumps under a raised home with good crawl space access on stable ground sits toward $3,000. A full-house restump with bearer and joist replacement, steel screw piles, asbestos removal, and engineering in a home with tight subfloor access on reactive clay pushes toward $25,000.
City and Regional Price Comparison
Sydney sets the baseline. Melbourne has the highest volume of restumping work nationally, driven by tens of thousands of post-war timber-floored homes on reactive basalt clay soils across the western and northern suburbs. Brisbane has strong demand for Queenslander restumping, where high-set homes provide generous working height that keeps labour costs more predictable than low-set southern homes.
Perth and Adelaide tend to run 10–15% above Sydney rates, reflecting smaller trade pools and materials logistics. Perth's Bassendean sand systems provide stable ground in most suburbs, but limestone subgrade in the Fremantle area and clay pockets in the eastern foothills create exceptions. Adelaide's reactive clay soils, particularly in the northern plains (Salisbury, Elizabeth) and southern suburbs (Morphett Vale, Reynella), drive persistent restumping demand.
Within any city, cost variation comes down to the specific property. A raised home on stable soil with generous crawl space and localised damage is the best-case scenario. A low-set home on reactive clay with tight access, widespread damage, and asbestos present is the worst case. Inner-city terraces with sandstone foundations (Sydney), heritage homes with original timber framing (Melbourne), and high-set Queenslanders on 140-year-old hardwood stumps (Brisbane) each present distinct structural challenges. An engineer's inspection is the only reliable way to scope structural work before committing to a price.
For homes where the structural work involves plumbing or electrical disconnection and reconnection (common during restumping or load-bearing wall removal), those trades will be quoted separately.
How We Calculate
Estimates are based on surveyed trade rates for licensed builders across Australian capital cities, adjusted for regional labour markets and material costs. All prices include GST. Figures cover standard residential structural repair work. Commercial buildings, heritage-listed properties, and multi-storey structures may fall outside these ranges. Material costs reference current supplier pricing from WoodSolutions and Master Builders Australia member data.