Are aluminium frames approved for composite decking?
Frame and board makers each set their own rules, and none we read publishes a complete list of approved aluminium systems. What they do say:
| Maker | What it says |
|---|---|
| Futurewood | Its aluminium span tables apply only with its own decking boards, brackets, splice, clip connectors and pedestal accessories. The frame supports CleverDeck and names no other board |
| NewTechWood | StructurAL joists work with NIVO pedestals and Cobra secret-fix clips. Its product page doesn’t list specific boards |
| Ekodeck | Its BAL-19 test result was obtained with aluminium joists and the 3 mm Quickfix system. The substructure must comply with the BCA and boards can’t sit directly on concrete |
| ModWood | Over concrete, battens (treated pine, steel, aluminium or fibreglass) must be at least 50 mm high and attached to the slab. We found no list of approved aluminium systems |
| Millboard | Describes its aluminium DuoSpan as low maintenance and highly corrosion resistant; DuoLift pedestals only for solid, stable bases. No Australian joist centres on that page |
| ClickDeck | Says its frame works with composite and natural timber decking. That is the vendor’s own claim |
What do you need to check?
Ask the board maker, in writing, whether your frame is acceptable and at what joist centres. Then ask the frame maker whether its span table covers the load of your board. Check four things:
- Joist centres. Most Australian composite boards allow 450 mm for residential use, closer for commercial or diagonal.
- Fixings. Futurewood supplies combo clips for timber or metal joists, and says to cut aluminium with a purpose-made blade.
- Warranty. Both warranties usually depend on following the guides.
- Bushfire rating. The frame’s report doesn’t make the board rated; see the composite decking page for BAL by board.
For frame details, see the aluminium frame overview and the joists page.
Questions
Can I use aluminium joists for composite decking?
Often, but it is the board maker who decides. Ekodeck reports a BAL-19 test result using aluminium joists with its 3 mm Quickfix system, and NewTechWood sells StructurAL for its boards. Futurewood's tables apply only to its own boards.
What is an aluminium sub frame for composite decking?
A subframe made of aluminium joists, used under composite boards. The boards fix to it with the maker's clips or screws, and the joist centres still follow the board maker's limit.
Sources
- ClickDeck flyer
- Futurewood CleverDeck Aluminium Deck Frame System Installation Guidelines, Appendix 1 Span Tables (V1, June 2024)
- ModWood Fixing - Over Concrete (April 2017)
- Ekodeck Designer Series Product Manual V10.25
- NewTechWood Deck Framing System
- Millboard AU Subframes Explained
- CleverDeck Xtreme Fixing Guidelines
- NewTechWood StructurAL Installation Guide 2021 AUS