Ask three suppliers to price the same backyard deck and you can get three very different numbers. That doesn’t always mean someone is overcharging. More often, each quote covers a different scope of work.
The boards are only one line on the bill. Framing, fixings, site preparation, labour and delivery sit underneath, and on many jobs they add up to more than the boards themselves. Here’s what drives the cost of the composite decking Melbourne homeowners are quoted for, and how to compare those quotes fairly.
1. The board price per square metre
Board prices depend on what’s inside the board: capped or uncapped, solid or hollow, thickness and finish. A capped board has a protective outer shell for better stain and fade resistance, and usually costs more.
The quoting unit matters as much as the number. A 145 mm board laid with a 5 mm gap needs about 6.7 lineal metres per square metre, so $15 a metre is really about $100 a square metre. Before you treat any composite decking Melbourne price as final, check whether it’s per metre, per board or per square metre, and whether it covers boards only.
2. Deck size, shape and waste
A 6 m × 4 m deck covers 24 square metres, but you won’t order exactly 24. Most installers add 5–10% for offcuts, and more for diagonal boards or picture-frame borders.
Shape matters too. Steps, curved edges, multiple levels and a deck that wraps around a pool all mean more cuts, more fascia and more hours. If the budget is tight, a simple rectangle gets you the most deck for the money.
3. The subframe and your site
A low deck on a flat, accessible block is the cheapest kind to build. A sloping site, reactive clay soil or an elevated deck needs more footings, bearers and joists, and sometimes an engineer or a building permit.
Replacing an old timber deck? Don’t assume the frame can stay. Composite boards may need joists closer together than the original deck was built with, and the timber has to be sound. Removing and disposing of the old deck is another line to check.
4. Labour, fixings and finishing
Labour is usually the biggest variable after framing. It depends on access, deck height, board direction and how much finishing work is involved.
Composite boards also need compatible hidden clips, starter clips, screws, fascia boards and end trims. Each piece is small, but across a large deck they add up, and non-approved fixings can void the warranty. Ask whether labour is a fixed price for the agreed scope or could change once work starts.
5. Custom lengths and delivery
Standard boards are around 5.4 metres long. A manufacturer that cuts to length can reduce joins and offcuts on long runs, although custom orders may carry a lead time.
Delivery depends on your suburb, order size and access. Long boards need a truck that can get close, so mention narrow driveways or rear-lane access when you ask for a quote.
6. How to compare quotes
Put every quote side by side, line by line: boards, waste allowance, subframe, fixings, fascia, site preparation, labour, delivery and rubbish removal. A cheap quote that leaves out framing isn’t cheap.
The better composite decking suppliers Melbourne homeowners deal with will itemise without being asked and explain what’s excluded. If a supplier won’t, take that as a warning.
Where Tuff Deck fits
Tuff Deck manufactures, supplies and installs composite decking from Dandenong South. Its website gives an indicative range of 100–150 per square metre, depending on design and requirements, and boards can be made to your required size. Send your measurements, a few site photos and your deck height, and ask for a quote that shows exactly what’s included.
Frequently asked questions
How much does composite decking cost per square metre in Melbourne?
Composite decking boards in Melbourne generally cost around $70 to $150 per square metre, depending on the product. At the time of writing (October 2026), imported boards were advertised from about $10 to $15 per lineal metre. Framing, fixings, labour and delivery are extra, so an installed deck costs considerably more.
How much does a 20 m² composite deck cost in Melbourne?
At a board price of $100 to $150 per square metre, 20 m² plus a 10% cutting allowance comes to roughly $2,200 to $3,300 in boards. Framing, fixings, fascia, labour and delivery come on top, and depend on your site and deck height. An itemised quote is the only reliable figure.
Is composite decking more expensive than timber?
Composite often costs more upfront than treated pine and some hardwoods, but it doesn’t need oiling or staining. Over 10 to 15 years, the oil, sanding and labour you save can close much of the gap. Compare the total cost of owning the deck, not just the board price.
Why do composite decking quotes vary so much?
Quotes vary mainly because they cover different scopes. One may include framing, fixings, delivery and labour while another prices boards only. Site access, deck height, design complexity and waste allowance also change the total. Compare quotes line by line rather than by the final figure.
Is it cheaper to install composite decking yourself?
DIY can save on labour for a simple, low deck, but mistakes with joist spacing, expansion gaps or fixings can affect performance and void the warranty. Elevated decks may also need a building permit in Victoria. Follow the manufacturer’s instructions, or pay for professional installation on anything structural.
How do I get an accurate composite decking quote?
Send the supplier your deck measurements, a simple sketch, site photos and the deck height. Mention access limits, any existing decking to remove, and features like steps or fascia. Then ask for an itemised quote covering boards, subframe, fixings, labour and delivery, with exclusions listed.
