At a Glance
Structural repair work in Sydney typically costs $3,000–$25,000 per job. This covers restumping, bearer and joist replacement, subfloor repairs, and load-bearing wall modifications. The wide range reflects how different a single room's worth of rotten joists is from a full-house restump with engineering and asbestos removal.
What's Included in the Price
A structural repair quote in Sydney covers an assessment of the damage, removal and replacement of affected structural members (stumps, bearers, joists), re-levelling where needed, and temporary support (jacking and propping) during the work. All structural timber framing must comply with AS 1684 Residential Timber-Framed Construction. An engineer's assessment or design is typically required for restumping and load-bearing modifications, and may be included in the builder's quote or charged separately.
Materials range from concrete stumps (standard) to steel screw piles (premium, faster installation). Labour is the largest cost component because of the physical difficulty involved, the need for temporary propping, and inspection requirements at various stages.
What Affects the Cost
- Number of stumps. Replacing 10–15 failed stumps under one section of the house is a fraction of a full restump covering 40–80 stumps.
- Stump material choice. Concrete stumps are the traditional replacement. Steel screw piles cost more per unit but install faster and avoid the excavation that concrete stumps require.
- Crawl space access. Subfloor areas with 500mm+ clearance allow workers to move around. At 300mm or less, every task takes longer. Some Sydney terraces and cottages have sections with almost no crawl space.
- Extent of timber damage. Localised rot in a single bearer is a contained repair. Widespread damage from moisture exposure or termites can mean replacing the entire subfloor frame.
- Engineering requirements. Structural work almost always needs an engineer's assessment. Load-bearing wall removals require a full engineering design. Engineering fees typically add $500–$1,500+ to the project.
- Asbestos presence. Many pre-1990 Sydney homes have asbestos sheeting in subfloor areas, behind cladding, or under flooring. Licensed asbestos removal must happen before structural work can proceed.
- Soil conditions. Sydney's geology varies significantly by suburb. Sandstone in the eastern suburbs and inner west provides stable foundations but makes excavation harder. Clay soils in the western suburbs are more reactive.
Replacing a handful of failed stumps under a raised home with good crawl space access sits toward $3,000. A full-house restump with bearer and joist replacement, steel screw piles, engineering, and asbestos removal in a home with tight subfloor access pushes toward $25,000.
Sydney-Specific Considerations
Inner-west terraces and cottages. Balmain, Glebe, Surry Hills, Newtown, Rozelle. Sydney's oldest housing stock sits in these suburbs, with many homes dating from the 1870s–1920s. Foundations range from sandstone block piers to early concrete stumps. These houses often have mixed construction – sandstone base walls with timber framing above – which complicates structural assessment. Subfloor access is frequently poor, with low clearances and limited entry points. Narrow lot widths and shared party walls in terraces add constraints that detached homes do not have.
Sandstone foundations. A defining feature of inner Sydney construction. Sandstone block piers and footings are common in pre-Federation homes. While sandstone itself is durable, the lime mortar between blocks deteriorates over decades. Repointing or underpinning sandstone foundations is specialist work, distinct from standard restumping, and not every builder has experience with it.
Western Sydney clay soils. Suburbs from Parramatta westward through Penrith and out to the Hills District sit on clay soils that expand and contract with moisture changes. This soil movement puts stress on stumps and footings over time. Homes built in the 1960s–1980s on these soils are reaching the age where stump deterioration becomes visible through uneven floors and cracking walls.
Strata and older apartment buildings. In older walk-up apartment blocks (common across the inner west and eastern suburbs), structural issues affect the entire owners corporation. Strata structural assessments require an engineer's report and body corporate approval before work proceeds. Individual lot owners cannot commission structural modifications independently.
Termite risk. Sydney's warm, humid climate supports active termite populations. Subterranean termites can cause significant structural damage to bearers and joists before the problem becomes visible at floor level. Any structural repair should include a termite inspection to determine whether the damage is isolated or ongoing.
Hiring a Licensed Carpenter in NSW
In NSW, a contractor licence is required for residential building work valued over $5,000 (including GST). Structural work falls under the builder or carpentry licence categories. Verify your contractor's licence through NSW Fair Trading.
Ask for:
- Current NSW contractor licence number (verify it online before signing anything)
- Proof of public liability and home warranty insurance
- A written quote that specifies the scope of structural work, materials, and whether engineering is included
- Evidence of an engineer's involvement for restumping or load-bearing modifications
- Confirmation of any council approvals required
Red flags: No licence number, unwilling to involve an engineer for structural work, or requesting full payment before starting. In NSW, home warranty insurance is required for any residential building work over $20,000.
How We Calculate
Estimates are based on current licensed builder and carpenter rates across the Sydney metropolitan area, adjusted for typical material and engineering costs in NSW. All prices include GST. Figures cover standard residential structural repair work. Heritage-listed properties, commercial buildings, and multi-storey structures may fall outside these ranges.