Cost to build a deck in Australia, 2026 prices by size and material
A new deck is one of the most asked-about home jobs in Australia. Expect $300 to $800 per square metre for treated pine, more for hardwood or composite. Here's what drives the number.
A new deck doubles your usable living space and lifts your house’s value. It’s also one of the most variable building costs in Australia. The same 20 square metre deck can run $6,000 if you’re DIY-keen with treated pine, or $35,000 if it’s hardwood, elevated, with steel framing.
This is a national 2026 cost guide. Your state, your access, and your material choice move the number a lot.
Per square metre, by material
| Material | Installed cost per m² (AUD) |
|---|---|
| Treated pine, ground level | $300 to $500 |
| Treated pine, elevated | $450 to $700 |
| Hardwood (merbau, spotted gum, blackbutt), ground level | $500 to $900 |
| Hardwood, elevated | $700 to $1,200 |
| Composite (Modwood, Ekodeck, Trex), ground level | $700 to $1,100 |
| Composite, elevated | $900 to $1,500 |
These figures include labour, materials, fixings, and a basic concrete or stump foundation. Council fees and any structural engineering reports are extra.
Realistic project totals
| Deck size and type | Total cost (AUD) |
|---|---|
| Small ground-level treated pine (10 m²) | $4,000 to $7,000 |
| Standard ground-level treated pine (20 m²) | $7,000 to $12,000 |
| Standard hardwood deck (20 m²) | $12,000 to $22,000 |
| Elevated hardwood deck with stairs (25 m²) | $20,000 to $35,000 |
| Composite deck with screened pergola (30 m²) | $25,000 to $50,000 |
What drives the price
- Height off the ground. Decks above 1m need structural certification, stronger framing, balustrades, and stairs. Each adds cost.
- Access for materials. Backyard with side gate access is cheap. Crane-required delivery to a steep block adds thousands.
- Foundation type. Soft ground or clay needs deeper footings. Concrete pads vs stumps vs steel screw piles all cost differently.
- Council approval cost. Some councils charge $300 to $1,500 in fees. A DA can take 6 to 12 weeks.
- Steel vs timber framing. Steel is more expensive upfront but lasts longer and is mandatory in some bushfire zones.
- Stairs and balustrades. A 4-step staircase with code-compliant balustrade adds $1,500 to $4,000.
When you need council approval
The rules vary by state and council, but as a national rough guide:
- Ground-level deck under 25 m², not attached to a dwelling, usually exempt
- Deck attached to a dwelling, usually needs approval
- Deck above 1m off the ground, usually needs approval
- Deck on a bushfire-prone property (BAL rating), usually needs specific compliance
- Deck near a boundary, council setback rules apply
Always check your local council’s exempt and complying development guidelines before pricing the job. A surprise DA halfway through is the worst kind of budget shock.
Hiring a chippy or builder
Decks are squarely chippy territory. For decks under $3,300 (QLD), $5,000 (NSW), or your state’s licensing threshold, a Cert III carpenter can build it. For larger decks attached to a dwelling, a contractor licence is required in every Australian state. Get three quotes, verify the licence number on the regulator’s online register, and don’t pay more than 10% upfront.
DIY pine deck, the realistic budget
A confident DIYer with weekend time can build a 20 m² ground-level treated pine deck for $3,000 to $5,000 in materials. Add tools you don’t own (impact driver, mitre saw, circular saw) and the saving versus hiring out narrows. The catch: any deck attached to a dwelling needs builder certification under most state rules, even if you build it yourself. Standalone garden decks are the DIY sweet spot.
Frequently asked questions
What's a typical deck cost in Australia?
$300 to $800 per square metre installed for treated pine, $500 to $1,200 for hardwood (spotted gum, blackbutt, merbau), $700 to $1,500 for composite (Modwood, Ekodeck, Trex). A 20 square metre deck typically runs $8,000 to $20,000 all-in.
Do I need council approval to build a deck?
Often yes. Most states allow small ground-level decks under exempt or complying development. Decks attached to a dwelling, decks above 1m height, or decks larger than 25 square metres usually need a development application. Always check with your local council before starting.
How long does it take to build a deck?
A simple 20 square metre ground-level deck takes a carpenter 4 to 7 days. Add 2 to 4 weeks for council approval if needed. Larger or elevated decks can stretch to 2 to 3 weeks of build time.
Treated pine or hardwood, what's the real difference?
Treated pine is cheaper upfront and well-suited to painting. Hardwood is twice the price but lasts 30+ years with minimal maintenance and looks better natural. Composite is the most expensive upfront but needs no oiling, no sealing, no replacement boards. Over 25 years, composite often works out cheaper than pine.