Australia calculator
Deck Building Cost Calculator
Estimate the cost to build a new deck in Australia. Adjust the deck size, the decking material, whether it is ground-level or raised, and whether you add a perimeter balustrade and a stair run to see an itemised low–high range in Australian dollars (GST inclusive) per square metre for your project.
How this calculator is built
Unit costs with sources
This model cites 4 sources for its line-item cost and regional labour inputs.
Regional labour adjustment
The state table applies local labour indexes only to labour-heavy line items.
Published methodology
The methodology page lists the formula, size drivers, labour model, and source links.
How this estimate is calculated
The model prices 5 project line items from published cost inputs. Quantities are driven by the deck's size, the decking material, whether it is ground-level or raised, and whether it includes a perimeter balustrade and a stair run. The selected scope and finish adjust those inputs, then the regional index changes only each line's labour share; material prices remain national.
The itemised midpoint is shown as a ±25% planning range. It is not a contractor quote: access, design choices, permits, availability, and site conditions can move the final price.
Read the full calculation notesEstimate your project
Change the default inputs to match your scope. The breakdown updates by line item.
Deck Building Cost by state: typical ranges
Each range applies that state's labour index to the labour-share line items of the default project; materials stay at national prices. Select a state for its full local breakdown and calculator.
| State | Typical range | Labour index | Permit |
|---|---|---|---|
| Australian Capital Territory | $10,998–$18,331 | 101% | Usually none |
| New South Wales | $11,035–$18,392 | 102% | Usually none |
| Northern Territory | $10,694–$17,824 | 95% | Usually none |
| Queensland | $10,768–$17,947 | 96% | Usually none |
| South Australia | $10,713–$17,855 | 95% | Usually none |
| Tasmania | $10,243–$17,071 | 85% | Usually none |
| Victoria | $10,869–$18,116 | 98% | Usually none |
| Western Australia | $11,376–$18,960 | 109% | Usually none |
Common questions
How much does it cost to build a deck in Australia?
Supplied and installed, treated pine runs about $200–$280 per m², hardwood about $300–$400 per m², and composite about $350–$550 per m², with a separately priced balustrade at $250–$600 per lin m — so a mid-grade 30 m² hardwood or composite deck with a timber balustrade lands around $13,000–$16,000. Prices shown are GST inclusive.
Is composite decking worth it over timber in Australia?
Composite costs more up front — often 30–50% above treated pine — but resists the termites, splitting, and greying that plague timber, and needs no annual oiling, which matters in Australia's harsh UV and humid north. Treated pine is cheapest to install; capped composite sits at the top. The 'Decking material' selector scales the estimate across these tiers.
Do I need approval to build a deck in Australia?
A low ground-level deck is often exempt development needing no approval, but a raised deck, one attached to the dwelling, or a deck in a bushfire-prone (BAL) or flood area usually needs building approval from a private certifier or council. Toggle 'Raised / elevated deck' and 'Include a stair run' to reflect the extra structure, and check whether a bushfire rating applies to your site.