The True Cost of Building and Owning a Deck
Posted by Renovator Mate on 15 Aug 2018
The true cost of decking can be difficult to determine. Factors such as material, labour and plans for your deck can make a big difference. However, when done properly, they can make the perfect addition to your home and garden.
One of the most surprising costs of owning a deck is the long-term expense of maintenance. The cost of the materials and labour needed to wash, sand, stain and seal decking can add up.
While decks constructed from natural timber must apply oils and other chemicals frequently to protect their decking, options such as composite wood have a much lower maintenance cost and don’t require oil or chemicals to protect them.
Timber decking does come with its own benefits, especially with its lower initial cost. However, over time it can often be a cheaper option to choose decking with a reduced maintenance cost.

What is the Cost of Decking Material?
Decks can be constructed from cheaper treated pine through to heavier and more expensive natural timbers.
When it comes to the price of your decking materials, factors such as type and thickness of your timber, as well as the size of your deck can all influence your cost. Prices included here are averaged from Australian costs.
Soft Woods
Soft woods are the cheapest option for decking but are more prone to splinters and other maintenance issues. They can be stained or painted and are relatively easy to work with. Soft wood decking may require re-application of oil or sealant every six to 12 months, depending on the amount of use and exposure to the elements. The most common softwood option for decking is treated pine.
Average Cost: Treated Pine $50 pm²
Hard Woods
Hardwood timber decking is generally more expensive than soft wood timber. While it’s stronger and more durable, it can also be more difficult to work with.
Hardwoods are more commonly used for decking and come in a range of popular options including Merbau, Blackbutt, Jarrah and Spotted Gum.
Average Cost: Merbau $60 pm², Blackbutt $85 pm², Jarrah $100 pm², Spotted Gum $110 pm²
Composite Wood
Composite wood is made from recycled timber fibre and plastic. It comes in a variety of styles, is easier to work with and is naturally resistant. Rather than depleting natural resources, composite material is used from wood that is already in circulation. It also doesn’t require staining, sanding, oils or other maintenance.
Average Cost: Moku, $105 pm², NewTechWood $125 pm², Trex $162 pm², Millboard $250 pm²

What is the Cost of Construction?
The circumstances and location of your deck can all influence your deck construction cost. These factors can include:
- Slope of the ground
- Elevation of the deck
- Shape of deck
- Fire risk of local area
If the deck is built on a slope, each relative increase in the steepness of the slope can increase the total cost by an average of $1,250. Each metre that the deck is elevated above ground can add an additional $2,500 to total costs.
Additions to your deck can also increase your construction costs and include:
- Balustrades
- Lights
- Stairs
- Roofing
Balustrades made of wood and steel wires cost an average of $150 pm, whereas glass balustrades cost an average of $250 pm. Adding LED downlights along the decking, including a switch back to the house will cost roughly $100 per light. Adding stairs to your deck can add an average $200 pm² to the total cost, while adding a roof to the deck can add on another $200 pm².

What is the Cost of Maintenance?
Deck Sealant: $13 per litre
Deck Surface cleaner: $25 per litre
Decking Oil: $12-$25 per litre
Decking usually requires about one litre of material per 10m² with a minimum of two coats of oil. More coats can also be applied for a darker colour.
The average cost of a twice-yearly clean, oil and seal for a 25m² deck is $375 per year.
Over the expected 15-year minimum deck life the average maintenance cost a timber deck, not counting labour or repairs, is $5,625.
What is the Total Cost of Decking?
According to data from tradesman contracting service Oneflare, the average labour cost of installing a deck is $4,900. Taking this into account, we can determine the average total cost for a 25m² deck, constructed without any additions and on flat ground.
Softwood (Treated Pine) 25m² Deck:
Materials: $1,350 + Construction: $4,900 = $5,850 + 15 year maintenance = $11,875
Hardwood (Blackbutt) 25m² Deck:
Materials: $2,295 + Construction: $4,900 = $6,795 + 15 year maintenance = $12,820
Composite (NewTechWood) 25m² Deck:
Materials: $3,375 + Construction: $4,900 = $8,275
While natural timber decking has its own benefits, over time it can become a more expensive option. No matter which decking material you choose, with the right plan in place for your budget you’ll enjoy a beautiful outdoor deck for years to come.
Author Bio
This article was written by Daniel Defendi, who recommends NewTechWood for composite material projects. You can catch Daniel on Google+ to discuss this piece.
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