What Does It Cost to Rebuild a Deck in Australia?
Rebuilding a deck in Australia typically costs between AUD $180 and $600 per square metre, depending on the chosen material and the scope of work required. The biggest cost variable is whether you need a full rebuild (subframe + boards) or just a resurface (boards only).
This guide breaks down the real costs of rebuilding a deck in Australia. It covers materials, labour, the factors that drive costs up or down, and how to decide whether a rebuild is the right move. Always obtain multiple quotes from licensed local builders for your specific project.
Table of Contents
How Much Does It Cost to Rebuild a Deck in Australia?
The total cost of rebuilding a deck depends on three main variables: the size of the deck, the materials you choose, and whether you hire a professional or do it yourself.
Here are typical all-in costs for a full deck rebuild in Australia (materials + labour + subframe + finishing):
| Deck Size | Budget Build (Treated Pine) | Mid-Range (Hardwood) | Premium (Composite) |
|---|---|---|---|
| 15 sqm | AUD $4,500–$7,500 | AUD $7,500–$12,000 | AUD $9,000–$15,000 |
| 25 sqm | AUD $7,500–$12,500 | AUD $12,500–$20,000 | AUD $15,000–$25,000 |
| 40 sqm | AUD $12,000–$20,000 | AUD $20,000–$32,000 | AUD $24,000–$40,000 |
These estimates assume a ground-level or low-level deck (under 1,000 mm above ground) on a flat block with standard soil conditions. Elevated decks, sloping sites, and complex designs cost more.
Important: These figures include the removal and disposal of the old deck. Demolition and waste removal typically add AUD $500 to $2,000 to the project, depending on deck size and access.
Use the EVODEK Decking Calculator to estimate material quantities for your specific deck dimensions.
Cost by Material Type
The decking boards are the most visible part of the rebuild. They also represent a significant portion of the total cost. Here is what each material costs in Australia.
| Material | Material Cost (AUD/sqm) | Installed Cost (AUD/sqm) | Lifespan | Annual Maintenance Cost |
|---|---|---|---|---|
| Treated Pine | $30–$60 | $180–$350 | 10–15 yrs | $200–$500 |
| Merbau | $60–$100 | $300–$450 | 15–25 yrs | $150–$300 |
| Spotted Gum / Blackbutt | $90–$140 | $400–$550 | 20–25 yrs | $150–$300 |
| Composite (WPC) | $80–$160 | $300–$600 | 25–30 yrs | $0–$50 |
| PVC | $100–$180 | $350–$650 | 25–30 yrs | $0–$50 |
Note: Installed cost includes subframe, fixings, and labour. Actual costs vary by location, site conditions, and builder.
Treated Pine
Treated pine is the most affordable decking material in Australia. They are readily available at hardware stores that sell building materials.
- Material cost: AUD $30–$60 per sqm
- Installed cost: AUD $180–$350 per sqm
- Lifespan: 10–15 years with regular maintenance
- Maintenance: Requires sanding, staining, and sealing every 1–2 years. Needs chemical termite treatment in high-risk areas.
Treated pine is a good choice for tight budgets. However, it has the shortest lifespan and the highest ongoing maintenance costs. Over 20 years, the cumulative cost of maintenance often exceeds the initial savings.
Hardwood (Merbau, Spotted Gum, Blackbutt)
Australian and imported hardwoods are the traditional premium choice. Merbau (imported from Southeast Asia) is the most popular. Spotted Gum and Blackbutt are native Australian species with excellent durability.
- Material cost: AUD $60–$140 per sqm (Merbau at the lower end, Spotted Gum and Blackbutt higher)
- Installed cost: AUD $300–$550 per sqm
- Lifespan: 15–25 years with regular maintenance
- Maintenance: Requires oiling every 1–2 years to maintain colour. Without oiling, hardwood weathers to a silver-grey tone. Hardwoods are naturally resistant to termites but not immune.
Hardwood gives the most natural, authentic look. It is heavier and harder to work with than pine, which increases labour costs.
Composite (WPC)
Composite decking is made from a blend of wood fibres and recycled plastics. It is manufactured to look like natural timber but requires almost no maintenance.
- Material cost: AUD $80–$160 per sqm
- Installed cost: AUD $300–$600 per sqm
- Lifespan: 25–30 years
- Maintenance: Wash with soapy water once or twice a year. No sanding, staining, sealing, or chemical treatments required.
Composite costs more upfront than treated pine but less over its full lifespan. It is also lighter than hardwood, making installation faster.
EVODEK composite decking boards use dual-screw co-extrusion technology. The result is a board with a density of 1.3 g/cm³ — denser than most competing composites. EVODEK boards are FSC-certified, tested for slip resistance and fire resistance under Australian conditions, and backed by a 25-year residential warranty (10-year commercial).
Explore the full range: EVODEK Garden Decking | EVODEK Boardwalk Decking
PVC (Cellular PVC)
PVC decking is a fully synthetic product. It contains no wood fibres.
- Material cost: AUD $100–$180 per sqm
- Installed cost: AUD $350–$650 per sqm
- Lifespan: 25–30 years
- Maintenance: Wash only. No staining or sealing.
PVC is the most moisture-resistant option. It is suitable for pool surrounds and marine environments. However, it tends to feel more plastic underfoot than composite. It also expands more in heat, which requires wider spacing during installation.
Factors That Affect the Total Cost
Deck Size
Larger decks cost more in total but often cost less per square metre. Builders can work more efficiently on larger, simpler decks. A 40 sqm deck typically costs 10–15% less per sqm than a 15 sqm deck.
Deck Height and Access
Ground-level decks (under 300 mm) require minimal subframe work. Elevated decks (over 1,000 mm) need deeper post footings, stronger bearers, and balustrades. The higher the deck, the higher the cost.
Difficult site access also increases costs. If materials cannot be delivered directly to the backyard (narrow side gates, steep slopes, no rear access), expect manual handling surcharges of AUD $500 to $2,000.
Site Conditions
Sloping blocks, rocky soil, and high water tables all increase foundation costs. A site with sandy, stable soil on flat ground is the cheapest to build on. A steep site with clay soil that needs retaining may add AUD $3,000 to $10,000 to the subframe cost.
Condition of the Existing Subframe
This is the single biggest cost variable in a rebuild. If the existing subframe is structurally sound, you can resurface only, replacing the boards while keeping the joists, bearers, and posts. This can cut the total cost by 30–50%.
If the subframe is compromised, it must be replaced. For example, rot in bearers, termite damage in posts, and rusted connectors. A full teardown-and-rebuild is significantly more expensive than a resurface.
Location
Labour rates and material costs vary across Australia. As a general guide:
- Sydney and Melbourne: Highest labour rates. Expect 10–20% above national averages.
- Brisbane, Perth, Adelaide: Close to national averages.
- Regional and remote areas: Material delivery costs can be significantly higher, but labour rates are sometimes lower.
Design Complexity
A simple rectangular, single-level deck costs less per sqm than a multi-level design with curves, built-in seating, or integrated planters. Every additional angle, level change, and custom feature adds to the labour time and material waste.
Council Approval
In most Australian states, a deck requires building approval if it exceeds 10 sqm in area, is more than 600 mm above ground level, or is attached to the house. Permit costs vary by council but typically range from AUD $200 to $1,500.
A rebuild that changes the footprint, height, or structural design of the original deck may need a new building permit even if the original deck was approved. Check with your local council before starting work.
Repair, Resurface, or Rebuild?
Not every ageing deck needs a full rebuild. Here is how to assess your options.
Step 1: Inspect the Subframe
The subframe is the skeleton of the deck: the posts, bearers, and joists that support the surface boards. If the subframe is solid, you may only need to replace the boards.
How to check the subframe:
- Push a screwdriver into the timber at various points. If it sinks in easily, the timber is soft and likely to be rotting.
- Check bearer-to-post connections. Loose, corroded, or missing brackets indicate structural weakness.
- Look for termite damage, mud tubes on posts, hollow-sounding timber when tapped, or frass (fine sawdust) around joints.
- Check that posts are not leaning or shifting at ground level.
If you are unsure, hire a licensed building inspector. An inspection costs AUD $200–$500 and can save you from either overspending on unnecessary work or under-spending on a dangerous structure.
Step 2: Use the Decision Matrix
| Condition | Recommended Action | Estimated Cost (25 sqm deck) |
|---|---|---|
| Boards worn but subframe solid | Resurface only — replace boards, keep subframe | AUD $4,000–$10,000 |
| A few boards damaged, subframe solid | Spot repair — replace damaged boards only | AUD $500–$2,000 |
| Some joists or bearers rotting, posts solid | Partial rebuild — replace damaged subframe sections + all boards | AUD $8,000–$16,000 |
| Posts shifting, major structural damage, termite damage in subframe | Full rebuild — tear down and start over | AUD $12,000–$25,000 |
| Deck is less than 15 years old, surface is grey/weathered but structurally fine | Refinish — sand and re-oil (hardwood) or pressure wash (composite) | AUD $500–$2,000 |
Step 3: Consider the Long-Term Cost
A resurface with treated pine costs less today but will need replacing again in 10–15 years. A rebuild with composite costs more now but should last 25–30 years with no ongoing maintenance. Over 30 years, a composite often works out cheaper.
Here is a simplified 25-year cost comparison for a 25 sqm deck:
| Scenario | Year 0 | Maintenance (25 yrs) | Replacement (at year 12–15) | 25-Year Total |
|---|---|---|---|---|
| Treated Pine (rebuild twice) | $6,000 | $6,000 | $6,000 | ~$18,000 |
| Hardwood (rebuild once) | $10,000 | $5,000 | — | ~$15,000 |
| Composite (build once) | $14,000 | $500 | — | ~$14,500 |
Composite’s higher upfront cost is offset by near-zero maintenance and no mid-life replacement. For homeowners who plan to stay in their home long-term, composite delivers the lowest total cost of ownership.
Tips for Reducing Deck Rebuild Costs
Keep the Subframe If You Can
This is the single most effective way to reduce costs. If the subframe is structurally sound, resurfacing with new boards saves 30–50% compared to a full rebuild. Have a building inspector confirm the subframe condition before making this decision.
Get Three or More Quotes
Pricing varies significantly between builders. Get at least three written quotes for the same scope of work. Make sure each quote specifies the same materials, the same deck design, and the same inclusions (demolition, waste removal, permits, railings, stairs).
Time Your Build
Deck builders are busiest in spring and early summer (September–December) when homeowners want their decks ready for the warm months. You may get better pricing by scheduling your build in autumn or winter (March–August) when demand is lower.
Supply Your Own Materials
Some builders charge a markup of 15–30% on the cost of materials. If you source the materials yourself (from a supplier like EVODEK or from Bunnings), you can eliminate this markup. However, check with your builder first. Some will not warranty work done with owner-supplied materials.
Choose a Simpler Design
Every extra level, angle, and built-in feature adds labour time. A simple rectangular, single-level deck is the most cost-effective shape. If the budget is tight, start with a basic platform and add features like railings, seating, and lighting later.
DIY Where You Can
Even if you hire a builder for the structural work (subframe, posts, footings), you can do some tasks yourself to save money:
- Demolition and old deck removal: saves AUD $500–$1,500
- Board laying: if you are handy and confident with the installation instructions. EVODEK provides detailed installation guides.
- Finishing touches: lighting, planter boxes, and furniture placement
Do not DIY structural work (footings, bearers, joists) unless you have trade-level experience. Structural failure is a safety risk and a liability issue.
Learn More: How to Save Money on Composite Decking?
Summary
Before committing to a full rebuild, have the existing subframe inspected. A sound subframe can save you 30–50% of the total cost. When choosing materials, consider the full lifecycle cost — not just the upfront price. Composite decking costs more to buy, but its 25-year lifespan and near-zero maintenance make it the most cost-effective option over time.
Frequently Asked Questions
Do I need council approval to rebuild a deck?
In most Australian states, yes — if the deck exceeds 10 sqm, is more than 600 mm above ground, or is attached to the house. A like-for-like replacement (same size, same footprint, same height) may be exempt in some councils, but this varies. Always check with your local council before starting. Permit costs range from AUD $200 to $1,500.
Can I keep my old subframe and just replace the boards?
Yes, if the subframe is structurally sound. This is called resurfacing. It cuts the total cost by 30–50%. Have a building inspector check the joists, bearers, posts, and connections before deciding. If only a few joists are damaged, a builder can replace those sections without tearing down the entire subframe.
How long does a deck rebuild take?
A straightforward resurface (boards only) for a 25 sqm deck takes 2–4 days. A full rebuild including demolition, subframe, boards, railings, and stairs takes 1–3 weeks depending on site conditions and weather.
Should I switch from timber to composite when rebuilding?
This depends on your priorities. If you want the lowest upfront cost and prefer the look and feel of natural wood, timber (treated pine or hardwood) is the right choice. If you want the lowest long-term cost, minimal maintenance, and a 25+ year lifespan, composite is the better investment. Many homeowners who are rebuilding a worn-out timber deck choose composite specifically because they want to avoid repeating the staining-and-sealing cycle.
What is the cheapest decking material in Australia?
Treated pine is the cheapest upfront, at AUD $30–$60 per sqm for materials. However, it requires the most maintenance and has the shortest lifespan (10–15 years). Over 20–25 years, treated pine is often the most expensive option when you factor in ongoing maintenance, repairs, and eventual replacement.
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