How do merbau and composite compare?
| Merbau | Composite | |
|---|---|---|
| Durability | Class 1 above ground, which WoodSolutions puts at more than 40 years | Set by the maker’s warranty, for example 25 years residential for several brands we list |
| Tannin | Hardwoods can leach extractives that stain paving below | None reported by the makers |
| Maintenance | Clean, then re-oil or re-stain | Clean; high-pressure advice differs by maker |
| Fixing | Stainless or hot-dipped galvanised; pre-drill | The maker’s clips or screws |
| Heat | Depends on colour and finish | ModWood says dark colours can get quite hot underfoot |
| Bushfire | Listed as bushfire-resisting timber for BAL-12.5 to BAL-29 | Depends on the board’s BAL documentation |
| Installed cost | $220 to $550 per m² on two guides | $200 to $700 mid-range, up to $900 premium |
What does merbau cost per metre?
Canterbury Timbers lists Merbau 90 by 19 mm at $7.15 per metre on 30 October 2026, GST status unconfirmed. That is roughly $75 per m² of boards with a 5 mm gap. See what decks cost for installed rates.
How do you stop merbau staining paving?
Use seasoned timber and apply a water-repellent finish to all faces including freshly cut ends, according to WoodSolutions. It also warns that iron filings from angle grinders can leave black iron stains.
What fixings does merbau need?
Hot-dipped galvanised or stainless, pre-drilled, at least 12 mm from edges and ends. Imported hardwood decking usually comes in 70 or 90 mm widths. See decking screws.
What about the legal side?
Imported timber is covered by Australia’s illegal logging prohibition. We couldn’t open the department’s guidance for this page, so ask your supplier how they meet it and read the due diligence page at agriculture.gov.au before you buy.
How do you choose?
Merbau gives a natural deck and a long above-ground life if you accept regular oiling and tannin bleed. Composite avoids both, but spacing, gaps and fixings follow each maker. Put both quotes into the decking cost calculator and see timber decking and composite decking.
Questions
Is merbau cheaper than composite decking?
It depends where in the range you look. Two guides put merbau at $220 to $550 per m² installed and mid-range composite at $200 to $700, so they overlap. Composite premium ranges reach $900.
Does merbau stain pavers?
It can. WoodSolutions says most hardwoods leach water-soluble extractives that can stain unsealed brickwork, concrete or paving beneath the deck. Seasoned timber and a water-repellent finish on all surfaces, including cut ends, reduce it.
Is merbau legal to use?
Merbau is an imported hardwood, and imported timber falls under Australia's illegal logging rules. We haven't read the department's guidance, so check the agriculture department's due diligence page and ask your supplier for evidence.