×GREENHILL TIMBERS×GREENHILL TIMBERSYour decking is warrantied for 25 years. Your frame isn’t.
Composite boards now outlast the treated-pine joists holding them up, often by decades. ClickDeck’s engineered aluminium subframe system fixes the mismatch: no rot, no termites, and a 50-year warranty under every board. Now in supply at Greenhill Timbers, Melbourne.
ClickDeck aluminium subframe · residential install, VIC
25–50 yrs
Warranty on today’s composite decking boards
5–15 yrs
Typical life of a treated-pine subframe in poor ventilation
1 in 3
Australian homes affected by termites (CSIRO)
50-yr
ClickDeck frame warranty — engineer-certified, Australian made
The problem
Why the frame under a composite deck rots first
Composite boards don’t absorb water — that’s the whole point. But it means every millimetre of rain that hits your deck is shed straight down through the board gaps onto the tops of your timber joists, where it sits in the shade with almost no airflow. The boards act as a collection system for the most vulnerable part of the structure.
Treated pine doesn’t solve it. H3 treatment only penetrates the outer few millimetres, and it’s rated for above-ground use with ventilation, not for the damp, enclosed void under a low composite deck. Three things let the rot in:
Screw penetrations
Every fastener punches through the treated shell into untreated heartwood. Hundreds of entry points per deck.
Cut ends
Docked joists expose raw end grain, the fastest path for moisture into any piece of timber.
Pooling on joist tops
Water funnelled off non-absorbent boards sits on the horizontal joist face, exactly where rot starts.
Frame vs frame
Treated pine vs ClickDeck aluminium
Match the frame to the board. If the surface is warrantied for 25+ years, the structure under it should be too.
| Treated pine frame | ClickDeck aluminium | |
|---|---|---|
| Structural warranty | None (treatment warranties exclude cut ends & screw holes) | 50 years |
| Rot & moisture | Vulnerable — worst under low, poorly-ventilated composite decks | Immune — aluminium can’t rot |
| Termites | At risk — AS 3660.1 management required | Termite-proof |
| Straightness | Bowed & twisted lengths sorted on site; moves seasonally | Dead straight, stays straight — flatter finished deck |
| Install speed | 2 people, cutting, re-treating ends, joist tape | Up to 70% faster — Tek screws, no pre-drilling, colour-coded plans |
| Minimum build height | ~400 mm practical minimum with ventilation | From 30 mm — build straight over concrete |
| Bushfire zones | Combustible | Non-combustible — compliant up to BAL-FZ with aluminium or steel posts |
| Engineering | Span tables, self-certified | Certified span & load documentation included (FORM126 / FORM15) |
Load ratings: 2 kPa live / 1.8 kN point (residential), 5 kPa / 4.5 kN (commercial). Compliance certificates for VIC & QLD supplied free with every kit. Warranty, install-speed and BAL figures as published by ClickDeck (clickdeck.com.au).
The system
One aluminium frame system, every deck scenario
ClickDeck is a modular Australian-made subframe of joists, bearers, brackets and adjustable pedestals, engineered for composite, timber or porcelain surfaces over concrete, membrane, roofing or natural ground.
- Joist profiles28 / 55 / 110 / 150 / 200 mm
- Build height30 mm – 850 mm+
- Max joist span (200 Profile)3.9 m continuous
- Stock lengths2.4 / 3.6 / 4.8 / 6.0 m
- Frame warranty50 years
- Fire ratingNon-combustible · BAL-FZ
- CertificationEngineer-certified, council approved
- FrameKits™16 preset sizes or cut-to-order
| Profile | Joist span | Bearer span | Cantilever | Best for |
|---|---|---|---|---|
| 28 × 50 | 700 mm | 600 mm | 200 mm | Ultra-low decks over concrete (from 30 mm) |
| 55 × 55 | 1200 mm | 1200 mm | 250 mm | Standard courtyards & patios |
| 110 × 50 | 1900 mm | 1700 mm | 400 mm | Raised residential decks |
| 150 × 50 | 2700–3000 mm | 2300 mm | 650 mm | Elevated & long-span decks |
| 200 × 50 | 3400–3900 mm | 2700 mm | 900 mm | Commercial & rooftop projects |
Who it’s for
Built for the trade. Simple enough for a weekend.
Builders & carpenters
Frame in half the labour, hand over engineered paperwork
No sorting bowed pine, no re-treating cut ends, no joist tape step. One person frames what used to take two.
- Up to 70% faster install than a timber subframe
- Certified engineering documents (FORM126 & FORM15) included with every kit
- Colour-coded build drawings with every order
- Trade pricing and take-off service through Greenhill Timbers
- BAL-FZ answer for bushfire-zone jobs where timber can’t go
Homeowners & DIY
Frame it in a weekend, forget it for 50 years
FrameKits™ arrive as a flat-pack with plans, brackets and screws. If you can drive a screw, you can frame a deck.
- 16 preset kit sizes, or made to measure for your space
- No pre-drilling: every connection is a Tek screw
- Goes straight over concrete, pavers or ground from 30 mm high
- Pairs with the composite and hardwood decking ranges in our yard
- 50-year warranty on the part of the deck you can’t see
Proven at every scale
10,000+ decks. Stadiums to courtyards.
The same profiles under a backyard deck in Thomastown carry public boardwalks at Marvel Stadium, The Alfred Hospital and Crown Towers Barangaroo.
The partnership
ClickDeck, now in supply where you buy your decking
Greenhill Timbers is Melbourne’s independent stockist for the ClickDeck system. A deck needs both the frame and the boards, and now one yard supplies the lot.
Frame, boards, fixings, one delivery. Our team quotes the complete deck: ClickDeck subframe matched to composite or hardwood decking from our range, with trade pricing for builders and honest advice for everyone else.
Bring your measurements, plans or just a photo of the space. We’ll spec the right profile, kit size and board, and have it on site fast.
Hardwood decking on ClickDeck — the frame carries timber boards just as well as composite.
Questions
Common questions about aluminium decking subframes
How long do timber deck joists last in Australia?
A treated-pine deck structure typically lasts 10–15 years, and as little as 4–5 in poor conditions. H3 pine is rated for above-ground use only; in ground contact, or in the damp unventilated space under a low deck, it can fail in 3–5 years. Cut ends and screw penetrations aren’t covered by treatment warranties.
Why does the frame rot before composite decking boards?
Composite boards repel water rather than absorbing it, so rain drains through the board gaps and pools on the tops of the joists, the least-ventilated and most vulnerable part of the deck. The boards can carry a 25–50 year warranty while the timber under them fails in a fraction of that time.
Do composite decks need a special frame?
They need a compliant one: most composite board warranties require specific joist spacing (typically 450 mm centres, 400 mm for diagonal laying), approved fasteners and minimum ventilation, and are void if the substructure doesn’t meet spec. ClickDeck kits are engineered to composite manufacturers’ spacing requirements out of the box.
Is an aluminium deck frame worth the extra cost?
The frame is a small share of a deck’s total cost, and the premium over pine is largely offset by labour: ClickDeck installs up to 70% faster with one person instead of two. Against that, replacing a rotted timber frame means lifting (and usually destroying) the boards on top: a rebuild commonly runs to several thousand dollars. Over the life of the deck, aluminium is the cheaper frame.
Are aluminium deck frames termite-proof?
Yes. Termites can’t eat aluminium. CSIRO hazard mapping suggests around 1 in 3 Australian homes is affected by termites, and AS 3660.1 requires termite management for new timber structures, decks included. An aluminium subframe removes the food source entirely.
Can I build a deck over concrete with ClickDeck?
Yes. The 28 mm profile with packers gets the build height down to just 30 mm, so you can deck straight over an existing slab, paved area or waterproof membrane without demolition. Adjustable pedestals handle falls and uneven surfaces up to 550 mm.
What deck frame do I need in a bushfire (BAL) zone?
BAL-40 and BAL-FZ sites effectively require non-combustible deck supports. ClickDeck aluminium is non-combustible and the system is compliant up to BAL-FZ when supported by aluminium or steel posts, with a fire report available for certification.
Can ClickDeck carry hardwood timber decking too?
It can. The frame takes composite, hardwood decking or structural porcelain pavers equally well. Greenhill Timbers supplies the boards and the frame, so we can quote the complete deck either way.
Build the frame once. Never build it again.
Get a complete deck quote from Greenhill Timbers, Thomastown — ClickDeck subframe plus boards.