How much does decking cost in Adelaide?
A new treated pine deck in Adelaide costs $165–$320 per square metre installed, merbau $275–$505 and composite $260–$645. As a whole job, a 25 sqm hardwood deck is $7,350–$14,700, typically $11,050. Adelaide spreads out rather than up, with 75% of dwellings separate houses and 51.3% of homes three-bedroom, against 39% nationally (ABS 2021 Census), so plenty of decks here are backyard jobs off a house on its own block. The figures cover supply and installation and include GST.
Comparing cities, or after the Australia-wide picture? See the national guide: Decking cost in Australia.
Detailed Pricing — Decking Cost in Adelaide 2026
| Service | Low | Typical | High |
|---|---|---|---|
| Treated pine deck (per sqm) | $165/sqm | $240 | $320 |
| Hardwood deck — merbau (per sqm) | $275/sqm | $385 | $505 |
| Hardwood deck — spotted gum (per sqm) | $320/sqm | $440 | $550 |
| Composite deck (per sqm) | $260/sqm | $505 | $645 |
| Small deck (15 sqm, hardwood) | $4,600total | $6,900 | $9,200 |
| Medium deck (25 sqm, hardwood) | $7,350total | $11,050 | $14,700 |
| Large deck (40 sqm, hardwood) | $11,950total | $17,500 | $23,900 |
| Deck steps (per step) | $165/step | $275 | $370 |
| Deck balustrade / railing (per lm) | $140/lm | $260 | $415 |
| Deck sanding + oiling (per sqm) | $23/sqm | $37 | $55 |
| Old deck demolition + removal | $18/sqm | $32 | $51 |
| Pergola over deck (basic timber or aluminium, about 4 x 4 m to 4 x 6 m) | $4,600total | $7,350 | $13,800 |
| Deck stairs (per flight, installed) | $920installed | $1,850 | $4,150 |
| Elevated / high-set deck surcharge (per sqm) | $46/sqm | $92 | $165 |
| Deck re-oil only (clean + 2 coats, no sanding, per sqm) | $14/sqm | $28 | $41 |
| Hardwood deck — blackbutt (per sqm) | $305/sqm | $415 | $570 |
| Composite deck — premium capped / solid-core, Trex class (per sqm) | $415/sqm | $525 | $830 |
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Prices include GST. Based on Adelaide metro area, October 2026. Outer suburbs may vary.
Adelaide’s Decking Market in 2026
Adelaide’s Mediterranean climate — hot, dry summers and mild winters — makes it one of Australia’s best cities for outdoor living, and decking is at the centre of that. Alfresco entertaining areas, pool decks, and backyard extensions are among the most popular home improvement projects in Adelaide, driven by a culture that embraces the outdoors for 8–9 months of the year.
Adelaide is one of the most affordable capital cities for decking, typically running below Sydney and Melbourne on both materials and labour. A standard 20 sqm merbau deck costs about $5,500–$10,100 in Adelaide (20 sqm at $275–$505/sqm). The savings come from lower labour rates, better material availability through local suppliers, and generally easier site access on Adelaide’s larger suburban blocks.
The biggest challenge for decking in Adelaide is the extreme UV exposure and summer heat. Temperatures regularly exceed 40°C, and Adelaide’s UV index is among the highest in Australia. Unprotected timber degrades faster here than in most other cities — decking oil needs reapplication every 6–12 months rather than the 12–18 months typical in Melbourne or Sydney. This harsh sun is driving strong growth in composite decking, which handles UV without any maintenance and now accounts for roughly 25–35% of new deck builds in Adelaide.
Termites are a significant consideration, particularly in suburbs near bushland and in the Adelaide Hills. H3-treated pine is the minimum for above-ground decking, and H4 is required for any posts or framing in ground contact. Spotted gum and ironbark are naturally termite-resistant, giving them an edge over treated pine in high-risk areas.
Under South Australia’s planning regulations, a deck used with an existing house needs no development approval if its floor is no higher than 500mm above natural ground and it is set back from the boundary — except in bushfire-prone areas and the Historic Area Overlay. Higher or larger decks typically need a building rules assessment. Heritage-listed properties in North Adelaide, Unley, and Norwood may have additional restrictions on visible outdoor structures.
How Decking Costs Vary Across Adelaide
Inner Adelaide & Eastern Suburbs
Unley, Norwood, Burnside, Glenelg, Prospect, Walkerville. Character homes on smaller blocks with established gardens. Heritage overlay zones in Unley, Norwood, and North Adelaide may restrict visible deck structures — check with your council before building. Narrower blocks and shared driveways in older suburbs can limit material delivery access and add to the job. These suburbs lean toward premium timber (spotted gum, merbau) and composite to match the character of the homes.
Northern Suburbs
Salisbury, Elizabeth, Parafield Gardens, Mawson Lakes, Gawler. Predominantly flat blocks with good rear access — ideal conditions for straightforward builds. Treated pine is the most popular choice in the northern suburbs where budgets are tighter. Newer estates around Mawson Lakes and Blakeview have modern homes with outdoor entertainment areas designed for decking integration. Strong competition among builders keeps rates at or below the Adelaide average. Watch for termite risk in areas near Para River and bushland corridors.
Southern Suburbs & Coast
Marion, Morphett Vale, Hallett Cove, Seaford, Christies Beach. Pool decking is particularly common in the southern suburbs, where backyard pools are a staple. Coastal properties (Hallett Cove, Christies Beach, Seaford) need stainless steel or galvanised fixings to resist salt air corrosion — standard zinc-plated screws will rust within 2–3 years near the coast. Composite decking performs well in coastal conditions and doesn’t splinter around pools. Generally affordable with good access and plenty of local deck builders.
Adelaide Hills
Stirling, Aldgate, Crafers, Bridgewater, Mount Barker. The most expensive area for decking in Greater Adelaide. Steep blocks require elevated deck structures with substantial subframes and engineered footings, often doubling the substructure cost. Virtually all Hills properties fall within bushfire-prone areas — all land in the Adelaide Hills Council area must meet bushfire construction requirements, and at BAL-40 and BAL-FZ decking must be non-combustible or tested for bushfire resistance. Difficult truck access on winding Hills roads adds to material delivery costs.
What You’ll Actually Pay — Common Adelaide Decking Jobs
Here’s what typical decking jobs cost across Adelaide in 2026, from the per-square-metre rows in our Adelaide table.
Ground-level alfresco deck — spotted gum, 20 sqm
$6,400–$11,000 total (20 sqm at $320–$550/sqm)
Adelaide’s most popular deck build. Spotted gum boards ($320–$550/sqm supplied and installed) on a hardwood subframe with concrete piers. Spotted gum is naturally Class 1 durable and termite-resistant — an important advantage in Adelaide where termite pressure is real. Ground-level decks under 500mm typically don’t need planning consent under SA’s rules. Finish with two coats of UV-resistant decking oil and reapply it regularly in Adelaide’s harsh sun. Allow 3–5 days for construction.
Pool surround — composite, 25 sqm
$6,500–$16,125 total (25 sqm at $260–$645/sqm)
Composite decking ($260–$645/sqm) is the ideal choice around Adelaide pools — it won’t splinter underfoot, handles chlorine splash without damage, and needs no oiling in the brutal summer sun. Brands like Modwood and NewTechWood offer slip-resistant profiles designed for pool surrounds. The subframe should be aluminium or H4-treated timber to handle constant moisture. Ensure proper drainage fall away from the pool and house. Composite stays warm but tolerable underfoot in summer — lighter colours are cooler. Allow 5–7 days for a pool surround build.
Budget backyard deck — treated pine, 15 sqm
$2,475–$4,800 total (15 sqm at $165–$320/sqm)
The entry-level option, popular in Adelaide’s northern suburbs and newer estates. H3-treated pine ($165–$320/sqm) on a simple subframe. Pine is Adelaide’s cheapest decking option but demands the most maintenance — unprotected pine greys and cracks quickly in Adelaide’s UV, so oil it regularly. If budget allows, spotted gum (15 sqm at $320–$550/sqm, or $4,800–$8,250) saves significantly in lifetime maintenance costs.
Elevated deck with pergola — Hills property, 20 sqm
$6,400–$11,000 for the decking, plus the substructure and engineering
Common in the Adelaide Hills where steep blocks mean decks often sit well above the ground. Includes engineered steel or heavy-timber post substructure (priced to the site), hardwood or BAL-rated composite decking ($6,400–$11,000 for 20 sqm of spotted gum), stairs ($165–$370/step), code-compliant balustrades ($140–$415/lm), and often an integrated pergola for summer shade (a basic pergola costs $4,600–$13,800). BAL-rated materials are mandatory in most Hills suburbs — timber may be restricted in BAL-40 and BAL-FZ zones. Building consent (a building rules assessment) is required, and the application must include calculations or reports showing the work complies. Allow 2–4 weeks.
Deck restoration — sand, repair, and reoil
Adelaide’s strong UV wears deck finishes down quickly. A professional restoration includes sanding back the grey, weathered surface to reveal fresh timber underneath, replacing split or cupped boards, tightening fixings, and applying 2–3 coats of UV-stabilised decking oil. The quote is built from sanding and oiling ($23–$55/sqm in our Adelaide table, or $14–$41/sqm for a clean and re-oil without sanding), plus any split or cupped boards that need replacing. A good quality UV-resistant oil (Sikkens, Cabots, Feast Watson) makes a measurable difference in Adelaide conditions.
Deck restoration cost in Adelaide (2026): sanding, re-oiling, and cheap decking when it is time to rebuild
Deck restoration in Adelaide costs $23–$55 per square metre for a full sand and re-oil, with $37/m² typical. A deck that is sound but faded only needs a clean and two fresh coats, $14–$41/m², which is the cheapest way to keep a timber deck looking right. Both are priced on the deck area; steps and balustrades add time.
| Job | Low | Typical | High |
|---|---|---|---|
| Deck sanding + oiling (per m²) | $23/m² | $37 | $55 |
| Deck re-oil only (clean + 2 coats, per m²) | $14/m² | $28 | $41 |
| Old deck demolition + removal (per m²) | $18/m² | $32 | $51 |
| Treated pine deck (per m²) | $165/m² | $240 | $320 |
| Hardwood deck — merbau (per m²) | $275/m² | $385 | $505 |
| Composite deck (per m²) | $260/m² | $505 | $645 |
| Small deck (15 m², hardwood) | $4,600 | $6,900 | $9,200 |
Restore or rebuild? Sanding and oiling suits boards that are grey, rough or patchy but still firm underfoot. If boards are split or soft, or the joists and bearers underneath are rotting, restoring the surface only hides the problem: demolition is $18–$51/m² and a new deck starts from $165/m² in treated pine. Ask the deck restorer to check the frame before quoting the finish.
Cheap decking in Adelaide: treated pine ($165–$320/m²) is the cheapest board to build with, against $275–$505/m² for merbau and $260–$645/m² for composite. It needs re-oiling most often, so the saving on the build is partly paid back in maintenance; composite costs more up front and is never oiled.
Deck maintenance that keeps the restoration cost down:
- Re-oil before the timber greys: a clean and re-oil is cheaper than a full sand.
- Keep it clean: leaves and dirt left on boards hold moisture against the timber.
- Check the fixings: a lifted nail or loose screw is a five-minute fix before it splits a board.
- Watch the joists: soft timber near the ground or the house wall is the first sign of rot.
- Shade and sun: the sunniest boards weather fastest and set how often the whole deck needs doing.
For a restoration quote in Adelaide that holds, give the deck area, the timber, how long since it was last oiled and whether there are steps or balustrades.
What Affects Decking Costs in Adelaide
Dry summers on timber
Adelaide is dry for much of the year: January and February get 20.1 mm and 20.2 mm of rain, the whole year only 524.5 mm, and January tops out at 28.7 °C on average (BOM averages). Long sunny spells grey and split unoiled boards, hence restoration tops local searches. A clean and re-oil is $14–$41; a full sand and oil is $23–$55.
Restore or rebuild
If the boards and frame are sound, restoring is far cheaper than starting again: re-oiling a 25 sqm deck at the typical rate comes to about $700, against $11,050 for a new hardwood deck that size. Where the subframe has rotted, removing the old deck is $18–$51 per square metre before any new work begins.
Cheap, composite or in between
Treated pine is the cheapest way into a deck at $165–$320. Standard composite boards run $260–$645 and premium capped boards $415–$830. Composite costs more than pine to lay but needs no oiling, which counts in a city where the summer sun works on timber year after year.
Hardwood species and deck size
Among the hardwoods, merbau is $275–$505, blackbutt $305–$570 and spotted gum $320–$550. Whole hardwood decks run from $4,600–$9,200 for 15 sqm to $11,950–$23,900 for 40 sqm, and the larger deck works out a little cheaper per square metre at the typical price.
Height and approval
In South Australia a deck whose floor is 50cm or less off the ground is among the minor works that need no development approval, with some conditions. Build higher, as on a sloping block, and you need approval, plus the elevated deck surcharge of $46–$165 per square metre. Once a deck is more than a metre up it needs balustrades, at $140–$415 a lineal metre.
Licence, contract and deposit
In SA anyone running a business that builds for others must hold a building work contractor licence, subcontractors included. A domestic building contract over $20,000 must be written and signed, and you then have 5 clear business days to cool off; up to that value the deposit is capped at $1,000. A medium deck tops out at $14,700, under that line, while a large one at the top of its band passes it.
Insurance on bigger jobs
Building indemnity insurance is required for domestic building work that needs council approval and costs $20,000 or more, and the builder arranges and pays for it. A 40 sqm deck built above the 50cm exemption height can reach that point ($23,900 at the top of its band), so ask for the certificate before work starts.
How to Save Money on Decking Cost in Adelaide
Frequently Asked Questions — Decking Cost in Adelaide
Our Methodology
These are independent estimates from public cost guides, marketplaces and industry rate data, and no tradesperson can influence them, so always get a few quotes. Last reviewed October 2026. Read our full methodology →