Timber vs composite decking: which is right for your project?
Choosing between timber and composite decking is the single biggest fork in most Australian decking projects, and it is a decision that is easy to get wrong if you only compare the upfront price tag. The two materials trade off differently across cost, lifespan and maintenance, and which one comes out ahead really depends on how you weigh those three things against each other for your own household.
On upfront cost, timber generally comes out cheaper. Treated pine commonly installs for around $200 to $280 per square metre, and hardwood species such as merbau, spotted gum and ironbark commonly range from about $280 to $420 per square metre. Composite decking commonly costs more to install, somewhere between $350 and $550 per square metre for good-quality boards, though some entry-level composite products can start lower, roughly $250 to $350 per square metre — our separate article on deck-building costs goes into these ranges in more detail if you want the fuller picture.
Lifespan tells a more complicated story than the cost comparison alone suggests. A well-maintained timber deck commonly lasts somewhere between 15 and 25 years, though that range depends heavily on species and how consistently it is cared for; treated pine's practical lifespan is often shorter, commonly around 10 to 15 years before significant remediation is needed, while premium hardwood can last 25 years or more with consistent maintenance. Composite decking is generally engineered for longer service life with less intervention, commonly rated at 25 to 30 years or more, and some quality composite products are rated anywhere from 25 up to 50 years depending on the specific product grade and how well it is installed.
Maintenance is really where the two materials diverge most sharply, and it is arguably the more important factor for a lot of homeowners than either the cost or the lifespan number on its own. Timber decking needs periodic cleaning along with oiling, staining or sealing to maintain both its appearance and its weather resistance, and in coastal or otherwise harsh, exposed environments that maintenance commonly needs to happen annually without exception — skip a cycle or two and timber will typically start to grey and check between treatments. Composite decking, by contrast, generally needs little more than routine washing; it does not require the ongoing oiling, staining or sealing that keeps a timber deck looking and performing well.
Taken together, this is why composite's higher upfront cost is commonly said to pay for itself within roughly 5 to 7 years once the avoided cost of annual timber maintenance is factored in — though that calculation depends on how diligently you would otherwise maintain a timber deck, and how much you value the reduced upkeep versus the lower starting price. Timber still has real advantages worth weighing: a natural look and warmth many homeowners prefer, and practical repairability, since an individual timber board can usually be sanded back or replaced on its own, which is not generally possible with composite boards in the same way. If you are comfortable with — or even enjoy — the annual maintenance routine, timber can remain a genuinely sound and more budget-friendly choice rather than simply the inferior option.
There is no universally correct answer here — it depends on your budget, how much ongoing maintenance you are realistically willing to do, and how long you plan to be in the property. This article is general information to help frame that decision, not a recommendation for your specific project. Our directory lists Australian carpenters and deck builders by area if you are ready to get quotes for either material.
Frequently asked questions
Timber is generally cheaper upfront. Treated pine commonly costs $200 to $280 per square metre installed and hardwood $280 to $420 per square metre, while composite commonly costs $350 to $550 per square metre, though entry-level composite can start around $250 to $350.
Generally yes. Composite decking is commonly rated at 25 to 30 years or more, sometimes up to 50 years for quality products. A well-maintained timber deck commonly lasts 15 to 25 years, though treated pine specifically is often shorter, around 10 to 15 years.
Timber needs periodic cleaning plus oiling, staining or sealing, commonly annually in coastal or harsh conditions, or it will grey and check over time. Composite generally needs little beyond routine washing and does not require oiling, staining or sealing.
Often, yes. Composite's higher upfront cost is commonly said to pay for itself within roughly 5 to 7 years once avoided timber maintenance costs are factored in, though the actual payoff depends on how diligently you would otherwise maintain a timber deck.