Guide To Timber Decking Cost

How Much Does It Cost To Build A Timber Deck?

Guide To Timber Decking Cost

Finding out how much timber decking cost is vital to planning a new decking project or renovation. Since there are different types of decking timbers, styles, and designs, the answer is not always clear-cut. This is why the professional builders from NO1 Decks Brisbane have compiled estimates and figures for different dimensions and timbers. This is to give you an idea of how much timber decking costs nowadays.

Decking Types

Hardwood Decking

Hardwood decking is a more expensive decking option but offers enormous value. For example, hardwoods can last up to 40 years, require less maintenance, and they are aesthetically pleasing. They are products of slow-growing trees; hence, hardwoods are rarer.

2. Softwood Decking 

Softwood is the cheapest decking material since it comes from fast-growing trees. The wood is easy to maintain and can last up to 25 years. On the downside, it is weaker than hardwood and won’t last as long. It also requires more maintenance, and the finish and colours can change quickly.

3. Composite Decking 

Composite decking is a product of plastic and wood. As a result, it combines the features of wood and plastic. For example, it is waterproof, requires little maintenance, and can last up to 50 years. As expected, composite decks are quite expensive, and you can’t stain or change their colours.

What Timber Is Available? 

The common timbers used for decking projects in Australia include:

Timber Decks


  • Treated pine


  • Ironbark: durable, fire and rot-resistant.
  • Blackbutt: durable and termite resistant.
  • Jarrah: durable, fire-resistant, and expensive.
  • Spotted Gum: dense and fire-resistant
  • Merbau: durable, affordable, rot and insect-resistant
  • Stringybark: white stringybark is only ideal for indoor use.

Does My Builder need to be licensed?

A decking builder should hold a builder or carpenter’s license or a licence for decking. Although the regulation varies from one state to another, below is the general guideline for builder’s licensing:

    • In NSW, any job worth more than $1,000 requires a licensed builder.
    • In Queensland, any job worth more than $3,300 requires a licensed builder.
    • In Victoria, any job worth more than $5,000 requires a licensed builder.
    • In South Australia, any decking job must be handled by a supervisor or building contractor.
    • In West Australia, you don’t necessarily need a licensed contractor, but you need a building permit.
  • In the Northern Territory, a licensed builder must ensure that your plans are to specifications, and you must submit the plan to the City Council.
  • In Tasmania, a construction manager or builder must manage your decking project.

Do I Need Building Or Council Approval For My Deck? 

Most states require that you obtain a building approval before embarking on a decking project. The approval is granted by a certifier after an assessment of your project. You need council approval if any of the following applies to your project:

  • The plan area is more than 10 square metres
  • The deck has a mean height of more than 2.1 metres
  • It is more than 2.4 metres high
  • It is longer than 5m along any side
  • The floor height of the deck from ground level is more than a metre.

Cost Breakdown Per Timber Type 

  • Treated pine: $150-$300 per sqm
  • Ironbark: $5.40 per linear metre (900 mm wide)
  • Blackbutt: $88 per sqm (86mm wide)
  • Jarrah: $75 per sqm (85 mm wide)
  • Spotted Gum: $105 per sqm (85mm wide)
  • Merbau: $60 per sqm (140mm wide)

Cost Breakdown Per Sqm 

Most decking projects cost an average of $300-$400 per sqm. However, the price can be as high as $500 once you add the cost of installation and materials. The average cost by size is below:

  • $6400 to $10,000 for a 20m2 deck
  • $9600 to $15,000 for a 30m2 deck
  • $12,800 to $20,000 for a 40m2 deck

Timber Deck Building

The installation price will include the cost of: 

  • Installing the deck
  • Installation concrete stumps
  • Digging stump holes
  • The bearers and joists, etc.

How Much Does It Cost To Build A Composite Deck? 

The average cost of building a composite deck starts from $100 per sqm to $350 per sqm. However, the price can be more depending on the brand.

Things That Will Affect The Cost Of Your Deck

  • Permit: if you need the approval to build a deck, you will need to pay before the council grants approval. Also, you will pay an extra $150 if you require a preliminary assessment.
  • Size and shape of your deck: unique shapes attract more price than regularly-shaped decks. Also, if you desire decorative elements and inlays, you will pay more.
  • Ground height: a deck on a raised or sloped elevation will require stairs, fence, roofing, or balustrades. All of these will further drive up the price.
  • Materials: as we’ve explained, decking materials are not created equal. Therefore, hardwood substructures are more expensive than their softwood counterparts.
  • Contractor cost: of course, you will need to pay for the labour, the price of which varies from one contractor to another.


To protect yourself and ensure you get the best out of your project, we recommend you interview more than one contractor and compare their written quotes.