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, which provides span tables graded by timber stress grade (F7, F17, MGP10, MGP12). Where footings are being replaced or altered, AS 2870 Residential Slabs and Footings governs the design based on site soil classification.
An engineer's assessment or design is typically required for restumping and load-bearing modifications. Engineering fees range from $490 for a site inspection to $1,500–$3,000+ for a full structural design. Materials range from concrete stumps ($400–$700 installed) to steel screw piles ($500–$1,000 installed, faster and better suited to reactive soils). Replacement bearers and joists run $20–$50 per lineal metre for hardwood (F17 spotted gum or ironbark) or $8–$20 per lineal metre for treated pine (H3/H4). For load-bearing wall removals, LVL beams from Wesbeam (E13/E14 grades, $15–$40/lm) or steel UB sections ($200–$500/lm supply) are specified by the engineer.
Labour is the largest cost component, with builder and carpenter rates in Sydney typically running $70–$120 per hour.
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. At $400–$1,000 per stump installed, the stump count is the single biggest cost driver for restumping work.
- Stump material choice. Concrete stumps ($400–$700 installed) are the traditional replacement. Steel screw piles ($500–$1,000 installed) cost more per unit but install faster and avoid the excavation that concrete stumps require, which matters in Sydney's varied geology.
- Crawl space access. Subfloor areas with 500mm+ clearance allow workers to move around. At 300mm or less, every task takes significantly longer. Many Sydney terraces and cottages have sections with almost no crawl space, sometimes requiring floorboard removal from above.
- 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, with hardwood joist materials alone running $20–$50 per lineal metre.
- Engineering requirements. A structural inspection ($490–$1,000) is the starting point. Load-bearing wall removals require a full engineering design with beam specifications ($1,500–$3,000+). A building permit or Complying Development Certificate is required for most structural modifications in NSW.
- Asbestos presence. Many pre-1990 Sydney homes have asbestos sheeting in subfloor areas, behind cladding, or under flooring. Licensed asbestos removal ($1,500–$5,000 depending on extent) 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 and more expensive. Clay soils in western Sydney (Parramatta to Penrith) are reactive and may require engineered footings.
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, engineering, and asbestos removal in an inner-west terrace with tight subfloor access pushes toward $25,000.
Sydney-Specific Considerations
Inner-west terraces and cottages. Balmain, Glebe, Surry Hills, Newtown, Rozelle, Leichhardt. 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 because the two systems behave differently under ground movement. Subfloor access is frequently poor, with clearances under 300mm and limited entry points. Narrow lot widths (often 4–6 metres) and shared party walls in terraces add constraints that detached homes do not have. Scaffolding and temporary propping in narrow side passages can add $2,000–$5,000 to the project.
Sandstone foundations. A defining feature of inner Sydney construction. Sandstone block piers and footings are common in pre-Federation homes across the inner west, eastern suburbs, and lower north shore. While sandstone itself is durable (some blocks are 150+ years old), the lime mortar between blocks deteriorates over decades, allowing movement and water ingress. Repointing or underpinning sandstone foundations is specialist work, distinct from standard restumping. Companies like Sydney Foundation Repairs offer mass concrete underpinning for sandstone foundations, which involves excavating below the existing footing and constructing reinforced concrete underpins. Not every general builder has experience with sandstone, so ask specifically about their track record with this type of foundation.
Western Sydney clay soils. Suburbs from Parramatta westward through Blacktown, Penrith, and out to the Hills District sit on clay soils that expand and contract with moisture changes. Under AS 2870, many western Sydney sites are classified M (moderate reactivity) to H1 (highly reactive). This soil movement puts ongoing stress on stumps and footings. Homes built in the 1960s–1980s on these soils are reaching the age where stump deterioration becomes visible through uneven floors and cracking walls. Steel screw piles are increasingly specified in these areas because they can be driven past the reactive zone into stable ground.
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. The assessment, approval, and tendering process for a strata building can take 3–6 months before work begins.
Termite risk. Sydney's warm, humid climate supports active termite populations, particularly in suburbs near bushland or with mature trees. Subterranean termites attack bearers, joists, and stumps from the ground up, and damage can be extensive before it becomes visible at floor level. Any structural repair should include a termite inspection ($250–$400) 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.
A good structural builder will:
- Provide their current NSW contractor licence number upfront (verify it on the NSW licence search)
- Carry public liability and home warranty insurance (mandatory for work over $20,000 in NSW)
- Give a written quote specifying the scope of structural work, stump material, bearer/joist species and grade, and whether engineering is included or separate
- Involve an engineer for any restumping or load-bearing modification
- Confirm whether a building permit or Complying Development Certificate is needed
Worth checking:
- The licence is current and covers building or carpentry work (not just general trade)
- The engineer's report is from a practising structural engineer, not just a building inspector
- The quote includes a contingency allowance or explains how unexpected damage (rotten bearers found during restumping) will be handled
- Home warranty insurance certificate is provided for jobs 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.