Decking

Timber vs Composite vs Fibre Cement

The three material types serve different priorities. Hardwood timber delivers natural warmth, stays cooler underfoot in direct sun, and suits builders and clients who value authentic aesthetics. Composite decking eliminates ongoing oiling and staining, resists rot and termites, and carries manufacturer warranties of 25–50 years. Fibre cement decking – such as the James Hardie HardieDeck system – is the only option rated to BAL-FZ (Flame Zone), making it essential for projects in the highest bushfire attack level zones where timber and most composites are not permitted.

Bushfire Compliance (BAL Ratings)

Decking in designated bushfire-prone areas must comply with AS 3959. Australian hardwoods like Spotted Gum and Blackbutt achieve BAL-29 naturally, while select composite products are rated between BAL-12.5 and BAL-40 depending on the brand. For BAL-FZ compliance, fibre cement is the primary solution – it is deemed non-combustible and suitable for flame zone construction. Always confirm the specific BAL rating of your chosen product before specifying, as ratings vary by brand and profile.

Hardwood Species Selection

For timber decking, species selection drives durability, maintenance, and cost. Spotted Gum is the premium choice – Class 1 durability, low tannin bleed, and BAL-29 compliance with a 40+ year lifespan. Merbau offers Class 1 durability at a lower price point but bleeds tannins heavily and requires careful detailing near light-coloured surfaces. Blackbutt provides a lighter coastal aesthetic with Class 1 strength. Treated pine is the budget option but demands more frequent maintenance and is not BAL-rated.

Maintenance and Lifetime Cost

Timber decking requires oiling every 6–12 months and periodic sanding to maintain appearance and performance. Composite decking needs only occasional washing – no oiling, staining, or sealing – making it the lowest-maintenance option over a 20+ year lifespan. Fibre cement requires resealing with a trafficable coating every 5–10 years. When comparing costs, factor in lifetime maintenance alongside the upfront material price – composite and fibre cement often cost less over the deck’s full lifespan despite higher initial outlay.

Getting the Right Advice

Your local Big River location stocks all three material types and can help you match the right product to the project – including BAL compliance verification, subframe specification, and fastener selection. For large-scale or commercial projects, our team can coordinate supply scheduling and provide technical documentation from manufacturers.