Building a deck can transform your outdoor area into a stylish and functional living space. Whether you want a place for weekend BBQs, an alfresco dining zone, or a spot to unwind in the evenings, a deck adds beauty and value to your property. However, the first question most homeowners ask is: what is the average cost of decking per square metre Australia? The cost of building a deck varies significantly depending on materials, labour, design, and additional features. This guide provides a detailed breakdown to help you plan your budget effectively and make informed decisions for your decking project.
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Why Decking Cost Estimates Are Crucial
Understanding the average cost of decking per square metre Australia is essential for:
Estimating your overall project budget.
Knowing the potential expenses beforehand helps homeowners allocate funds effectively and avoid overspending. Without a clear cost estimate, you risk encountering budget blowouts during construction.Choosing between materials like timber, composite, and PVC.
Each material comes with a different price range, lifespan, and maintenance requirement. Cost estimates allow you to balance aesthetics, durability, and affordability.Deciding between DIY and professional installation.
A realistic budget lets you weigh whether to handle installation yourself or hire experts. While DIY may save labour costs, professional installation ensures quality, safety, and compliance with building codes.Avoiding unexpected costs for site preparation, permits, and accessories.
Additional expenses, such as levelling uneven ground, applying protective finishes, or installing railing systems, can quickly add up. Accurate budgeting helps account for these hidden costs and prevents unpleasant surprises.
Main Factors Affecting Decking Costs
2.1 Material Type
The choice of material is the biggest cost driver. The most common options are:
Treated Pine – Affordable and widely available but requires regular sealing or staining to maintain its appearance and durability. While it has a lower upfront cost, maintenance costs over time should be factored into the total price.
Hardwood (Merbau, Jarrah, Spotted Gum) – More expensive but offers a rich appearance and long lifespan. These premium timbers are highly sought after for their natural beauty and strength, making them ideal for high-end decks.
Composite Decking – Made from a mix of wood fibres and plastic, it is low-maintenance and durable. It is also resistant to fading, cracking, and pests, which makes it a popular choice for homeowners seeking a long-term solution.
PVC Decking – Fully synthetic, weather-resistant, and long-lasting, but comes with a premium price tag. PVC options are ideal for coastal regions where moisture resistance is critical.
2.2 Deck Size
Larger decks naturally cost more due to higher material and labour requirements. However, the cost per square metre can sometimes decrease slightly with larger projects, thanks to economies of scale. For instance, bulk material purchases may lower unit prices, and contractors often offer discounted rates for bigger projects.
Additionally, larger decks often require more structural support and foundations, which can increase costs. Still, the long-term value of a spacious deck—especially for outdoor entertainment—can justify the investment. When planning size, consider how the space will be used and whether future expansions are likely.
2.3 Design Complexity
Simple, rectangular designs are easier and cheaper to build, making them ideal for budget-conscious homeowners. However, if you opt for multi-level layouts, curved edges, or integrated features like seating and lighting, expect additional costs.
Complex designs require more precise cutting, framing, and labour hours. In some cases, specialised tools or craftsmanship may be needed, further driving up expenses. While these enhancements add visual appeal and functionality, they also significantly influence your final budget.
2.4 Labour Costs
Labour rates vary across Australia. Major cities such as Sydney and Melbourne generally have higher rates compared to regional areas due to demand, living costs, and market conditions. Professional builders also charge more for intricate designs and premium materials.
DIY installation can lower labour costs substantially, but it comes with risks. Without proper skills, mistakes can lead to structural issues, safety hazards, or costly repairs. For most homeowners, hiring experienced professionals ensures a high-quality finish and compliance with local building codes.
2.5 Site Conditions
Sloping land, uneven ground, or poor soil conditions require additional preparation and structural support, adding to overall expenses. For example, retaining walls, extra posts, or foundation work may be necessary to create a level and stable surface.
Additionally, accessibility to the site can influence costs. Tight spaces, steep driveways, or limited delivery access may increase labour time and handling fees. Addressing these factors early helps avoid delays and unexpected budget overruns.
Average Cost of Decking Materials Per Square Metre
3.1 Timber Decking
Treated Pine Decking
Price Range: $200 – $350 per m² (installed)
Pros: Cost-effective and versatile, making it a great option for budget-friendly projects. It’s widely available and suitable for both small and large decks.
Cons: Requires annual maintenance to prevent decay and weather damage. Long-term maintenance costs may make it less economical over time.
Merbau Decking
Price Range: $280 – $450 per m² (installed)
Pros: Attractive appearance, natural resistance to termites, and impressive durability. Merbau’s rich colour enhances outdoor aesthetics and adds value to properties.
Cons: Can leach tannins and requires regular oiling to maintain its finish. It is also slightly more expensive than treated pine.
Hardwood Decking (Jarrah, Spotted Gum)
Price Range: $320 – $500 per m² (installed)
Pros: High-end look, excellent strength, and weather resistance. Hardwood decks offer exceptional longevity and natural elegance.
Cons: Higher upfront cost and maintenance requirements, including oiling and sealing to preserve appearance and prevent cracking.
3.2 Composite Decking
Price Range: $350 – $600 per m² (installed)
Advantages: Minimal maintenance, resistant to warping, splintering, and pests. Composite decking is ideal for homeowners seeking a modern, low-upkeep solution with long-lasting performance.
Drawback: Higher initial investment compared to timber. However, lower maintenance costs may balance out the expense over the deck’s lifetime.
3.3 PVC Decking
Price Range: $400 – $700 per m² (installed)
Advantages: Waterproof, durable, and long-lasting. Perfect for coastal or high-rainfall areas where moisture can damage natural timber.
Drawback: Expensive and may lack the natural look of timber. While it offers excellent weather resistance, some homeowners prefer the warmer aesthetics of wood or composite options.
Regional Cost Variations Across Australia
The average cost of decking per square metre Australia also depends on where you live.
Sydney & Melbourne – Expect to pay at the higher end due to increased labour and material costs.
Brisbane & Gold Coast – Prices are slightly lower, but premium materials may still command high rates.
Perth, Adelaide & Regional Areas – Labour rates may be lower, but remote delivery of materials can add extra costs.
Additional Costs Beyond Decking Boards
5.1 Permits and Council Approvals
Some councils require building permits for decks above a certain height or size. Fees can range from $150 to $1,000.
5.2 Subframe and Footings
Proper structural support is essential for safety and longevity. This can cost $50–$150 per m² depending on ground conditions.
5.3 Railings and Balustrades
Adding safety and style, railings can cost $200–$500 per linear metre, depending on material (timber, glass, or stainless steel).
5.4 Stairs and Steps
Multi-level or elevated decks require stairs, which can add $500–$2,000 or more depending on design.
5.5 Lighting and Accessories
Integrated LED lighting, power outlets, and seating features can add $500–$3,000 to the overall budget.
DIY Decking vs Professional Installation
6.1 DIY Decking
DIY decking can reduce costs significantly by eliminating labour fees, bringing expenses down to around $100–$400 per m² (materials only). However, you need carpentry skills, tools, and an understanding of building codes.
6.2 Professional Installation
Hiring licensed decking contractors ensures structural integrity, compliance with regulations, and a high-quality finish. While costs are higher, it provides long-term value and peace of mind.
Cost Comparison: Short-Term vs Long-Term Value
When evaluating the average cost of decking per square metre Australia, it’s important to consider not just upfront expenses but also maintenance and lifespan.
Timber Decks – Lower initial cost but higher ongoing maintenance (oiling, staining, repairs).
Composite Decks – Higher upfront cost but minimal maintenance, making them cost-effective over time.
PVC Decks – Premium price with the longest lifespan and lowest maintenance needs.
Budget Examples for Different Deck Sizes
Small Deck (10 m²)
Treated Pine: $2,000 – $3,500
Composite: $3,500 – $6,000
Medium Deck (20 m²)
Merbau: $5,600 – $9,000
Composite: $7,000 – $12,000
Large Deck (40 m²)
Hardwood: $12,800 – $20,000
PVC: $16,000 – $28,000
Tips for Reducing Decking Costs
Opt for simple designs and shapes.
Compare quotes from multiple builders and suppliers.
Choose cost-effective materials like treated pine or entry-level composite.
Build during off-peak periods when labour costs may be lower.
Final Thoughts
The average cost of decking per square metre Australia in 2025 ranges from $200 to $700, depending on material, design complexity, and location. Timber remains a popular choice for its classic appeal, while composite and PVC are excellent low-maintenance alternatives.
By carefully planning your budget, considering long-term value, and consulting professionals, you can create an outdoor deck that adds style, comfort, and value to your home.
