How Much Does Decking Cost In Australia

Most decking projects start on a Sunday afternoon, standing at the back door looking at a patch of dead lawn that nobody uses, working out whether the barbecue could live out there instead. It is one of the few renovations that changes how you actually spend your weekends.

Then the quotes arrive and the mood shifts, because they do not agree with each other and none of them explains why.

Part of the reason is something the rest of the internet will not tell you. There is no published Australian benchmark for what an installed deck costs per square metre. We checked.

The Archicentre Australia Cost Guide 2026 covers roofing, plumbing, fencing and flooring, and contains no decking rate. BMT's 2026 Construction Cost Table publishes whole-building rates only.

Rider Levett Bucknall's 2026 Riders Digest carries no decking line.

Neither the Housing Industry Association nor any state building authority publishes one. Rawlinsons does, on pages 155 and 163, but it sits behind a $450 paywall.

Every per square metre decking figure circulating online, including the ones in this guide, is somebody's market observation rather than an independent benchmark. We would rather tell you that than pretend otherwise. What follows is the verifiable part: real board prices, the standards your deck has to meet, and the questions that separate a good quote from a cheap one.

What Decking Materials Actually Cost

Start with what you can check yourself. These are live retail board prices, supply only, with no substructure, fixings, stumps, balustrade or labour included.

Board prices checked at Bunnings on 20 September 2026. The per square metre column is our own arithmetic, assuming a 4 mm board gap, not a published figure.

Those numbers are worth sitting with, because they reframe the whole decision. The boards are rarely the expensive part. On a typical build the substructure, footings, fixings, balustrade and labour together cost several times what the decking surface costs, which is why two quotes using identical boards can still land thousands apart.

As a working guide for the full installed job, most Australian decks land somewhere between $250 and $550 per square metre once everything is counted. Simple ground-level pine sits at the bottom, elevated hardwood or composite with stairs and balustrade sits at the top, and difficult access or engineered footings push past it. Treat that as orientation, not a quote, because no independent source publishes it.

What Is Driving Prices Right Now

Here is the part most decking articles get backwards. Timber is not what is making your deck expensive.

Australian Bureau of Statistics producer price indexes show output prices for house construction rose 2.0 per cent in the June quarter of 2026 and 5.9 per cent across the year. But the timber, board and joinery input to house construction fell 0.2 per cent in the March quarter and rose only 2.8 per cent over the year, well below the 4.1 per cent rise in house construction output prices across the same period. Labour and non-timber inputs are doing the work.

The rises are also uneven by state. Over the year to June 2026, house construction prices rose 11.5 per cent in Tasmania, 8.8 per cent in Western Australia, 8.5 per cent in South Australia and 8.0 per cent in Queensland, against 4.8 per cent in New South Wales and 3.7 per cent in Victoria. If you are building in Hobart or Perth, a quote from last spring has aged badly.

Choosing Between Pine, Hardwood And Composite

The standard version of this comparison is that pine is cheap and short-lived, hardwood lasts decades, and composite is maintenance free. Two of those three are wrong.

How Long Each Material Actually Lasts

Under AS 5604, the Queensland Government rates kwila, sold here as merbau, at above-ground durability Class 1 with a life expectancy beyond 40 years. Spotted gum and blackbutt are also above-ground Class 1. WoodSolutions, the Forest and Wood Products Australia program, publishes the same figures.

There is a catch on merbau that almost nobody mentions. That Class 1 rating is for above-ground use. In ground, merbau drops to Class 3, at 5 to 15 years, which is worse than spotted gum or blackbutt. Merbau makes excellent decking boards and poor posts in soil.

Treated pine deserves a fairer hearing than it usually gets. WoodSolutions' Timber Service Life

Design guide models decking specifically and predicts onset of decay in H3-treated pine decking boards at 35 to 60 years depending on climate zone. The common claim that a pine deck lasts 10 to 15 years is not supported by the decay modelling. What is true is that pine decks are usually replaced long before they rot, because of cupping, splintering, fastener failure and simply looking tired. Those are real reasons to choose hardwood. Rot is not the main one.

The Maintenance Question, Answered Properly

The widely repeated line that pine needs oiling every 12 to 18 months while hardwood needs it annually has no source behind it, and it misunderstands how coatings work. No Australian technical guide sets a different maintenance interval for pine than for hardwood. The interval is set by the coating you choose and how exposed the deck is.

Timber Queensland's Residential Timber Decks data sheet specifies reapplying clear finishes at roughly six monthly intervals, decking stains every two to five years depending on pigment load, and paints every five to seven years depending on exposure. WoodSolutions gives life to first maintenance as one to three years for oil, three to six years for stain and seven to ten years for paint. Cabot's frames it as an annual inspection rather than an annual recoat: check each year for changes in colour or water repellency, and recoat when the timber tells you to.

So if annual maintenance is the thing you want to avoid, the answer is not necessarily composite. It might just be a pigmented stain instead of an oil.

Composite Is Low Maintenance, Not No Maintenance

The manufacturers say this themselves, which is worth knowing before you pay the premium.

Trex states that its decking requires far less maintenance than wood but does require some, comparing it to washing your car. Ekodeck recommends a general clean at least annually to minimise surface oxidation. ModWood describes its product as relatively maintenance free but specifies regular sweeping and periodical cleaning, and expressly says not to use high pressure cleaners on it.

Read the warranties closely, because mould is where they narrow. Ekodeck caps mould and mildew cover at two years regardless of the headline warranty length. ModWood's Natural Grain warranty excludes fading, staining, mould, fungi, bacteria, algae and mildew outright. Stain cover is also time limited, with ModWood requiring spills to be removed within 72 hours and Trex within a week.

Warranty terms across the brands available in Australia run from 10 years on ModWood Natural Grain residential, through 15 to 30 years across the Ekodeck range depending on series, to 25 years on NewTechWood and ModWood Xtreme Guard. ModWood's Xtreme Guard is pro-rata from year 11, and the recovery percentage is lower for installations north of the Tropic of Capricorn.

Heat, And The Number You Should Not Trust

You will see it claimed that dark composite boards exceed 60 degrees in northern Australia. No credible source supports any absolute surface temperature figure. We looked at manufacturer testing, standards bodies and the peer-reviewed literature, and the 60 degree figure in circulation traces back to an accelerated weathering chamber setting, not a field measurement.

What is supported is more modest and more useful. Ekodeck's own testing, using an infrared thermometer on a clear 29 degree day, found its boards ran 4 to 7 degrees hotter than equivalent timber boards. Trex acknowledges its decking gets hot in direct sun and advises care so that skin, particularly children's, does not have extended contact with the surface. Composite runs hotter than timber. Nobody has published how hot.

A Sourcing Point On Merbau

Merbau is the most popular hardwood decking board in the country, and the timber industry's own body has reservations about it.

The IUCN Red List assesses Intsia bijuga as Near Threatened. WoodSolutions states on its own merbau page that the species is harvested from tropical forests and may in some cases be sourced from forests legally converted to other land uses, or where controls are inadequate, and advises checking with your supplier because certified merbau is available in Australia.

To be clear about what this is not: merbau is not CITES listed, and Australia's illegal logging laws place due diligence obligations on importers and processors, not on you.

But if the provenance matters to you, ask your builder or supplier for certification and chain of custody, and consider spotted gum or blackbutt, which carry the same above-ground durability rating and are grown here.

When Your Deck Needs Approval

This is where the standard advice online is most wrong. The frequently repeated rule that decks under 10 square metres and less than 600 millimetres above ground are exempt in most states is incorrect in every state we checked. The 600 millimetre figure does not appear as an approval threshold in any Australian instrument. The recurring number is one metre.

New South Wales is far more generous than the internet suggests, at 25 square metres rather than 10. Victoria is far stricter, with no exemption at all. Getting that backwards is the difference between a straightforward job and a stop work notice.

Victoria adds a second layer worth knowing. A planning permit can be triggered separately from the building permit, including by a Heritage Overlay where the deck is visible from a street or public park, and in several residential zones by a finished floor level more than 800 millimetres above natural ground on smaller lots. The planning permit has to come first.

Western Australia has its own second layer, because the Residential Design Codes govern setbacks and open space independently of the building permit, so development approval may be needed before you lodge.

The Safety Rules That Change The Build

Four things here are worth reading before you approve a design, because each one can force a change late and expensively if it surfaces after the frame is up.

Barriers And Balustrades

The trigger is not what most articles say. Under the National Construction Code 2022 Housing Provisions, clause 11.3.3, a barrier is required where it is possible to fall one metre or more, measured from the trafficable surface to the surface beneath. That last part matters on sloping sites and above retaining walls, where the deck may be well under a metre above the ground at the house and well over it at the far corner. The barrier itself must be not less than one metre high above the deck floor.

There is a detail that surprises people. The rule prohibiting climbable horizontal elements between 150 and 760 millimetres only applies where it is possible to fall more than four metres. On a typical domestic deck, horizontal wire or rail balustrades are not prohibited by that clause. Confirm the current opening and gap dimensions with your building surveyor, because the wording changed between code editions and we would rather you check than take a number from us.

If The Deck Is Near A Pool

The common claim that balustrades are compulsory around pool areas under AS 1926 misreads the standard. AS 1926.1 governs pool safety barriers, not balustrades, and it does not require a balustrade on a pool deck. Any balustrade there is required by the one metre fall rule instead.

What AS 1926 does do is more important for your build. A deck abutting a pool barrier is treated as the finished ground level, which re-sets the point from which the barrier's 1200 millimetre height is measured. Build a deck against an existing compliant pool fence and you can make it non-compliant without touching the fence. Steps and level changes must be set back at least 500 millimetres from the barrier.

Pool barrier law is state law, not one national rule. Queensland applies its own pool safety standard under Queensland Development Code MP 3.4, referencing the 2007 editions of AS 1926.1 and 1926.2, while Victoria applies the 2012 edition. New South Wales requires registration on the state Swimming Pool Register. If your deck goes anywhere near a pool, this needs to be designed, not assumed.

Bushfire Prone Land

AS 3959:2018 handles decks at clauses 5.7 through 9.7, and the bushfire-resisting timber species list is Appendix F, not Appendix E as it is often cited.

There are exactly seven species on that list: blackbutt, kwila or merbau, red ironbark, river red gum, silvertop ash, spotted gum and turpentine. Note what that means. Being a hardwood is not the test. Jarrah and grey ironbark are not on the list.

The requirements tighten in stages. At BAL-12.5 and BAL-19, treated pine decking is permitted across most of the deck, and is only excluded within 300 millimetres of a glazed element sitting less than 400 millimetres above the deck. From BAL-29, the whole deck surface must be non-combustible or bushfire-resisting timber. At BAL-40 and Flame Zone, the options narrow again to non-combustible materials, fibre cement sheet, or systems tested to AS 1530.8.1 and AS 1530.8.2 respectively.

Composite decking needs care here, because it is often described as non-combustible. It is not. Wood-plastic composite is combustible and is not deemed to satisfy at BAL-29 or above on material grounds. Specific products qualify only where that product has been tested as a system to AS 1530.8.1 by a NATA-accredited laboratory, and then only to the level certified. If you are on bushfire prone land and considering composite, ask for the test certificate and the BAL it covers.

One design lever worth knowing: enclosing the subfloor to the wall requirements for your BAL removes the material requirements for supports and framing at every level from 12.5 to Flame Zone.

How The Deck Attaches To The House

This is the single most important thing missing from most decking guides, and it is a structural safety issue rather than a cost one.

The National Construction Code has a specific Deemed-to-Satisfy provision at H1D11 for attaching decks to external walls, and it only applies within tight limits: not in an alpine area, not more than three metres from finished floor to the top of the footing, no cantilever, imposed load not exceeding 2 kPa, and a supporting wall that is either core-filled reinforced concrete masonry or steel or timber framing continuous to the footing with no openings or lintels.

Most Australian houses are masonry veneer, which is outside those limits. Where the provision does not apply, the attachment must be designed by a professional engineer or other appropriately qualified person. The alternative, which is often the better answer, is to make the deck self-supporting on its own posts and piers rather than bolting it to the house at all.

Ask any builder quoting your job which of those two they are proposing. It tells you a great deal about the quote.

Treatment Levels And Termites

Timber treatment is not one grade. WoodSolutions and Timber Queensland both specify H3 or better for decking boards and above-ground framing, in-ground durability Class 1 or H4 for framing within 150 millimetres of the ground, and H5 for posts embedded in soil. A quote specifying H4 posts is specifying the wrong thing.

Fixings matter too. Hot-dipped galvanised or stainless steel is the requirement, with stainless steel within one kilometre of the coast or one metre of a pool edge. Electroplated fasteners are unsuitable outdoors.

On termites, a deck built hard against the house can conceal the inspection zone that a termite management system depends on, and the National Construction Code requires a durable notice recording the system used and its installation date. Speak to whoever installed your existing system before the deck goes on.

Where The Money Actually Goes

Several things move a quote, and most of them are decided before anyone picks up a tool.

Deck size is the obvious one, but shape matters more than area. A simple rectangle attached to the back of the house is the fastest and cheapest thing to build. Curves, built-in seating, planter boxes and multiple levels add material and labour together, and stairs connecting levels are among the most labour intensive elements on any deck.

Site conditions come next. A flat, stable, accessible site needs minimal preparation. Sloping blocks, rock or soft clay mean deeper footings, excavation or retaining wall

work before the deck starts, and often steel posts and engineered connections rather than standard timber bearers. If the deck sits over a pool pump, hot water system or stormwater pit, access panels have to be designed in rather than cut in later. Our concrete slab cost guide

is useful background if footings turn out to be the issue.

Labour is usually the largest single component. For context on what sits underneath a charge-out rate, the Building and Construction General On-site Award sets a minimum hourly rate of $31.95 for a Level 3 carpenter in residential building from July 2026, including industry and tool allowances, and the ABS puts average hourly earnings for technicians and trades workers at $46.50. Charge-out rates sit well above both, because they carry insurance, vehicles, tools, overheads and non-billable time. No official source publishes deck builder charge-out rates, so treat any figure you see as observation rather than data.

Additional features are worth pricing as separate line items rather than absorbing into a lump sum. Stairs, balustrades, built-in seating, lighting and shade structures each have their own scope, and a quote that bundles them gives you nothing to compare. If a builder will not itemise, that is information in itself.

How To Bring The Cost Down Without Regretting It

Use treated pine for the substructure and spend on the boards you actually walk on. The framing is hidden and its job is structural, so provided the treatment level is right, premium timber underneath buys you nothing you can see.

If a deck is not the answer, paving

or a wider landscaping

scheme may serve the same space for less.

Keep the shape simple. A single level rectangle with no curves and no built-in joinery is the cheapest deck to build and the fastest to hand over.

Consider whether the deck needs to attach to the house at all. A self-supporting deck avoids the engineering, flashing and fire and thermal complications of bolting into an external wall.

Check the approval pathway before you finalise the design, not after. In New South Wales, keeping the deck within 25 square metres and under a metre high can keep the whole thing in exempt development. In Victoria, no design choice avoids the building permit, so budget for it from the start.

Compare quotes on scope, not just price. The cheapest number is often the one that leaves out flashings, proper footings or the right treatment level. If you want a sense check on whoever you are dealing with, our guides on verifying a tradie's licence in each state

and how to find a good tradie

are the two worth reading before you commit.

Frequently Asked Questions

These are the questions that come up most often once people get past the headline price.

How Much Does Decking Cost Per Square Metre In Australia?

No Australian authority publishes an installed per square metre decking benchmark, so any figure you see is market observation rather than data. What can be checked is board cost: roughly $42 to $50 per square metre for treated pine, $65 to $78 for merbau, and $103 to $142 for composite, supply only at retail prices as at September 2026. Installed, most decks land somewhere between $250 and $550 per square metre once substructure, footings, fixings, balustrade and labour are counted.

Do You Need Council Approval To Build A Deck?

It depends entirely on your state, and the widely quoted rule about 10 square metres and 600 millimetres is wrong. New South Wales allows up to 25 square metres as exempt development if the floor is under a metre high. Victoria requires a building permit for any deck attached to a house, regardless of size. Queensland allows up to 10 square metres subject to four other limits. Western Australia has no deck exemption at all. Tasmania exempts decks under a metre high with no area limit. Confirm with your council before you finalise the design.

How Long Does A Timber Deck Last?

Longer than most guides suggest. WoodSolutions' decay modelling predicts onset of decay in H3-treated pine decking at 35 to 60 years depending on climate. Merbau, spotted gum and blackbutt are all rated above-ground durability Class 1 under AS 5604, with a life expectancy beyond 40 years. In practice decks are usually replaced for cupping, splintering, fastener failure or appearance well before the timber fails structurally, and the substructure, fixings and detailing matter as much as the board species.

Is Composite Decking Really Maintenance Free?

No, and the manufacturers say so. Trex describes its decking as requiring far less maintenance than timber but still requiring some. Ekodeck recommends an annual general clean. ModWood specifies regular sweeping and periodical cleaning and warns against high pressure cleaners. Composite removes oiling and sanding, which is a genuine benefit, but every major brand sold here either caps or excludes mould cover in its warranty, and stain cover usually requires spills to be cleaned within days.

Can You Build A Deck On Bushfire Prone Land?

Yes, with material restrictions that tighten as the Bushfire Attack Level rises. At BAL-12.5 and BAL-19 treated pine is permitted across most of the deck. From BAL-29 the whole surface must be non-combustible or one of the seven bushfire-resisting timber species listed in Appendix F of AS 3959:2018. Composite is combustible and only qualifies where the specific product has been tested to AS 1530.8.1, so ask for the certificate and the BAL it covers.

Compare Decking Builders Across Australia With Trade Heroes

A deck is one of the more forgiving renovations to get right and one of the more annoying to get wrong, because the mistakes tend to be invisible until they are not. The wrong treatment level on a post, a balustrade that misses the fall rule, a deck bolted to a masonry veneer wall without an engineer, a pool fence made non-compliant by the thing built next to it. None of that shows up in a photograph.

So the useful move before you spend anything is to get several builders looking at the same site with the same brief, and to compare what they say about footings, treatment levels, attachment method and approvals rather than only what they say about price.

Trade Heroes is a directory. We list builders and carpenters by category and location so you can compare them and contact them directly. We do not build decks, we do not price them, and we do not take a cut of your job.

You can find decking specialists through Trade Heroes in Perth

, Sydney

, Adelaide

, Melbourne

, Hobart

or Brisbane

, and start the conversation with better questions than you had ten minutes ago.