Merbau vs Composite Decking: Which Is Better for Sydney?
The Great Aussie Deck Debate
If you're building a deck in Sydney, chances are you've already hit the merbau vs composite question. It's one of the most common dilemmas for homeowners across the city — and for good reason. Both materials have loyal fans, and both come with genuine pros and cons.
Let's cut through the marketing and give you a straight comparison so you can make the right call for your home, budget, and lifestyle.
What Is Merbau?
Merbau (also known as kwila) is a tropical hardwood that's been a staple of Australian decking for decades. It's naturally dense, durable, and has that rich reddish-brown colour that Aussies love. Most merbau is sourced from Southeast Asia and the Pacific Islands.
Merbau Pros
Merbau Cons
What Is Composite Decking?
Composite decking is an engineered product made from a mix of wood fibres and recycled plastics (usually HDPE). Brands like Trex, ModWood, and NewTechWood are popular in Australia. It comes in a range of colours and wood-grain patterns designed to mimic natural timber.
Composite Pros
Composite Cons
Cost Comparison for Sydney
Here's a rough guide for 2025 pricing in Sydney (supply and install):
| Material | Cost per sqm (installed) |
|---|---|
| Merbau | $280 – $450 |
| Mid-range composite | $350 – $500 |
| Premium composite | $450 – $600+ |
Keep in mind that merbau's ongoing maintenance costs (oil, time, or paying someone to do it) add up over the years. When you factor in 10+ years of oiling, composite can actually work out cheaper long-term.
How Do They Handle Sydney's Climate?
Sydney throws everything at your deck — scorching summer sun, heavy rain, coastal salt air, and the occasional hailstorm.
Merbau handles this well thanks to its natural density and oil content. It's a proven performer in coastal and humid environments. However, it will move with the seasons — expect some expansion in wet weather and contraction in dry spells.
Composite is engineered to resist moisture, UV, and insects. It won't swell, rot, or attract termites. However, darker colours can get uncomfortably hot in direct afternoon sun — worth considering if your deck faces west.
Which Should You Choose?
Go with merbau if:
Go with composite if:
Still Not Sure? Visualise It First
The best way to decide is to actually see what each material would look like on your home. With DeckVision's free AI visualiser, you can upload a photo of your backyard and preview different decking materials instantly — no commitment, no sales calls.
Get a free AI deck visualisation →
Frequently Asked Questions
Frequently Asked Questions
Is merbau decking good for Sydney?
Yes, merbau is excellent for Sydney's climate. It's naturally durable (Class 1 rated), handles humidity and coastal conditions well, and has been a popular choice for Australian decks for decades. Just remember it needs annual oiling to maintain its appearance.
How long does composite decking last in Australia?
Quality composite decking typically lasts 25–30 years or more in Australian conditions. Many manufacturers offer 25-year structural warranties. Unlike timber, it won't rot, crack, or be attacked by termites.
Is composite decking worth the extra cost?
It depends on your priorities. Composite costs more upfront but requires virtually no maintenance over its lifespan. When you factor in the cost of oiling merbau every year for 20+ years, composite often works out similar or cheaper long-term.
Does composite decking get hot in the sun?
Yes, darker composite colours can get hot underfoot in direct sunlight, especially on west-facing decks in Sydney summers. Choosing lighter colours or capped composites with heat-reflective technology can help reduce this.
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