Decking Timber Prices in Australia (Materials Only)
| Timber | Price per m² |
|---|---|
| Treated Pine | $55–$80 |
| Merbau | $85–$120 |
| Blackbutt | $100–$140 |
| Spotted Gum | $110–$150 |
| Composite | $140–$200 |
Full Installation Cost — 20m² Deck
- Treated Pine: $3,500–$5,000
- Merbau: $5,500–$7,500 (best value upfront)
- Spotted Gum: $7,000–$9,500 (premium)
- Composite: $8,500–$11,500
These figures include materials and standard installation labour for a straightforward, low-height 20m² deck. Elevated decks, balustrades, stairs and difficult site access all add to the total — use the Decking Cost Calculator for an estimate tailored to your exact deck.
Lifespan & Best Long-Term Value
| Timber | Lifespan | Cost per Year of Life* |
|---|---|---|
| Treated Pine | 15–20 yrs | ~$222/yr |
| Merbau | 25–35 yrs | ~$217/yr |
| Spotted Gum | 40–50 yrs | ~$178/yr — best value |
*Based on average installed cost for a 20m² deck divided by expected lifespan, before ongoing maintenance costs.
Our Recommendation
Merbau is the right call for most homeowners — the best all-round balance of upfront cost, look and durability. Spotted Gum is worth the extra spend if you're planning to stay long-term and want the best lifetime value. Treated Pine makes sense for a tighter budget or an investment property where you're less focused on longevity.
🧮 Get an Exact Estimate
Use our Decking Cost Calculator to estimate materials, labour and total cost for your specific deck size and timber choice.
Frequently Asked Questions
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