Deck Building Costs: Materials, Labour & Hidden Fees
Seeking an outdoor entertaining area to enjoy those Perth evenings? No matter if you live in Baldivis, Joondalup or beachside Cottesloe, working out what the cost is upfront could prevent a budget blowout and a few nasty surprises down the track. Prices in Perth fluctuate depending on materials, site conditions and level of design complexity, but a snapshot can help make the planning process less daunting. So, how much does decking cost in Perth?
Here’s what you need to know about decking costs in 2026:
MATERIALS (per m²):
- Treated pine: $200–$250
- Hardwood such as Jarrah or Merbau: $320–$500
- Composite decking: $350–$600
LABOUR
- Installation: $150–$210 per m²
- Total supply and install: $350–$710 per m²
TYPICAL PROJECT COSTS:
- Small (10–20 m²): $4,000–$7,000
- Medium (30–40 m²): $7,000–$15,000
- Large (50 m²+): $15,000–$25,000+
This blog will cover material choices, labour considerations, and hidden fees that influence final decking costs in Perth.
Understanding Perth Deck Building Costs Per Square Metre
If you want expertise in decking work for your property, try to find deck builders near me to get local decking contractors. You can also contact us at Boda Building Group for quality craftsmanship and get a free decking quote today.
- Perth average 2026: $350–$710 per m² for complete installation
- Materials only: $200–$600 per m²
- Labour only: $150–$210 per m²
Decking Cost Calculation Example
30 m² deck (5 m × 6 m)
BUDGET TIMBER – Treated Pine
- Materials: 30 m² × $220 = $6,600
- Labour: 30 m² × $150 = $4,500
- TOTAL: $11,100
PREMIUM HARDWOOD – Merbau
- Materials: 30 m² × $400 = $12,000
- Labour: 30 m² × $180 = $5,400
- TOTAL: $17,400
COMPOSITE – Low Maintenance
- Materials: 30 m² × $450 = $13,500
- Labour: 30 m² × $170 = $5,100
- TOTAL: $18,600
What Affects Deck Costs in Perth?
There are a number of practical elements that affect the cost of decking in Perth. Every home is unique, and even decks of the same size have varying costs depending on the following factors.
- Material choice: This is the major cost variable and is typically about 40-50% of the budget. Treated pine wood decking cost is the lowest.
- Deck size: Generally, large decks are cheaper per m2 as labour and machinery are spread over a greater area.
- Height and levels: Multi-level decks need additional structural support and scaffolding, which increases staffing costs.
- Design complexity: Curved edges, built-in seating, steps and one-of-a-kind patterns require more time and skill. For instance, decks with pools are likely to cost more.
- Site access: Narrow entry points and side access can add 15-25% for manual handling of materials. Budget for higher costs if you need to hire Perth roof carpentry experts to install a deck.
- Perth location: For homes in coastal suburbs, there is the added cost of marine-grade fixings and corrosion-resistant materials to combat salty air.
- Substructure requirements: Ground conditions determine footing depth and engineering needs, which can raise costs.
Perth Advantage: In general, reliable sandy soils are preferred for decking Perth, and costs may be lower than those for reactive clays found in the east.
Complete Material Cost Breakdown
The prices of decking per square metre can fluctuate from one manufacturer to another, and vary depending on the bidding of deck contractors and the sourcing price. Here’s a breakdown of the most popular decking materials to help you decide which one is right for your project:
Treated Pine Decking (Budget-Friendly)
- Cost: $200–$250 per m² (supply and install)
- Materials only: $40–$60 per m²
A treated pine deck is the most cost-effective. Perth outdoor carpentry specialists pressure treat the wood to protect against termites and rot when properly maintained. Its lighter weight allows for faster installation, saving on labour expenses.
Why Popular
- Most affordable decking option
- Readily available across Perth
- Easy to cut and install
- Can be stained or painted to suit different styles
Drawbacks
- Requires oiling or staining every one to two years
- Shorter lifespan of around 15–25 years
- Can develop splinters as it ages
- Prone to warping or twisting in Perth heat
Real Perth Example – Treated Pine
A 25 m² treated pine deck in Ellenbrook:
- Materials at $50 per m²: $1,250
- Treated pine subframe: $620
- Galvanised fixings: $160
- Labour, three days at $520 per day: $1,560
- Initial oil treatment: $280
- TOTAL: $3,870
Hardwood Timber Decking (Premium Natural)
- Cost: $320–$500 per m² (supply and install)
- Materials only: $60–$140 per m²
Hardwood timber decking is considered a premium option in Perth due to its natural beauty, strength, and longevity. It holds up under relentless sun and ranks high for resale value. You will find different varieties of hardwood in Perth. Here are a few common ones:
Popular Perth Species
| Timber | Cost per m² | Characteristics | Best For |
| Jarrah | $320–$650 | Rich red, WA native, very durable | Heritage homes, premium projects handled by commercial carpenters |
| Merbau | $280–$420 | Dark brown, tropical hardwood | Most popular choice |
| Spotted Gum | $350–$650 | Honey tones, Australian native | Contemporary aesthetics |
| Blackbutt | $320–$580 | Pale honey, weathers to silver-grey | Coastal properties |
Why Perth Homeowners Choose Hardwood
- Lifespan of 50–100 years
- Natural character and grain variation
- Withstands Perth’s intense sun
- Adds long-term property value
- Requires oiling only every two to three years
Real Perth Example – Hardwood
A 35 m² Merbau deck in Mount Lawley:
- Merbau boards, including 3 m² waste: $2,900
- Structural hardwood frame: $1,200
- Stainless coastal-grade fixings: $350
- Labour, five days at $520 per day: $2,600
- Pre-oiling treatment: $525
- TOTAL: $7,575 ($437 per m²)
Composite Decking (Low-Maintenance)
- Composite decking cost per m2: $350–$600 per m² (supply and install)
- Materials only: $120–$200 per m²
Composite decking is made from a mix of wood fibres, recycled plastics and a small amount of bonding agent, including tints and additives to replicate the look and feel of timber while increasing the low-maintenance life span. A deck composite is proven to be popular all across Perth, particularly in coastal settings and with busy families.
Perth Market Leaders
- Trex: $150–$200 per m²
- Modwood: $100–$160 per m²
Why Growing in Perth
- No sanding, staining, or oiling
- Will not splinter, rot, or warp
- Warranties ranging from 25 to 50 years
- Resistant to termites
- Consistent colour finish
- High resistance to stains and fading
Considerations
- Can become very hot in Perth’s summers, with surface temperatures exceeding 70°C
- Higher upfront cost compared to timber
- Can scratch under heavy impact
- Repairs are more difficult than timber
Heat Mitigation Tips
Experienced deck builders in Perth recommend choosing lighter colours that help reflect heat. Textured boards stay cooler than smooth finishes, and shade structures such as pergolas or sails significantly reduce heat build-up.
Real Perth Example – Composite
A 40 m² Trex decking cost in Scarborough:
- Composite boards: $7,200
- Aluminium corrosion-resistant substructure: $2,400
- Concealed fixings: $480
- Labour, four days at $550 per day: $2,200
- TOTAL: $12,280 ($307 per m²)
Lifetime Cost Comparison – Perth Conditions
| Material | Initial Cost (30 m²) | Maintenance | Replacement / Repairs | 30-Year Total |
| Treated Pine | $7,500 | $4,500 | $1,500 | $13,500 |
| Hardwood Timber | $12,900 | $2,250 | $750 | $15,900 |
| Composite | $15,000 | $0 | $0 | $15,000 |
Assumptions Used
- Treated pine requires oiling every two years at $300, plus partial board replacement after 15 years
- Hardwood requires oiling every three years at $225, with minor repairs after 20 years
- Composite requires cleaning only, with no structural maintenance
Labour Costs Breakdown Perth
Labour makes up a significant proportion of the deck installation cost. It revolves around the following:
- Site preparation and basic levelling
- Frame construction, including joists, bearers, and posts
- Deck board installation and fixing
- Basic finishing and site cleanup
Hidden Costs Most Perth Homeowners Don’t Expect
Aside from materials and labour, there are a few other costs that can creep up on you during any deck project. Knowing these ahead of time helps you estimate the average deck cost accurately.
Council Permits and Approvals ($0–$1,500)
Council permits and approvals are not required for all residential carpentry services in Perth. In terms of decking, they are required in the following scenarios:
- Decks over 10 m² in some council areas
- Decks higher than 500 mm
- Structures within 900 mm of a boundary
Typical Permit Costs
| Item | Estimated Cost |
| Application fee | $110–$800 |
| Building surveyor if required | $300–$1000 |
| BAL assessment in bushfire areas | $400–$600 |
The processing time is at the council’s discretion. For a standard application, apply at least 10–15 business days in advance. For complex or heritage properties, extend that time to four to eight weeks.
Site Preparation ($500–$3,000)
Another surprise outlay is often the preparation of the site. Old landscaping, lumpy soil or removal of past structures can tack on a few thousand dollars before the decking installers even start working.
| Category | Work Type | Typical Cost |
| Ground Clearing | Vegetation removal | $300–$800 |
| Stump grinding | $150–$400 per stump | |
| Levelling uneven ground | $500–$1,500 | |
| Existing Structure Removal | Old deck demolition | $25–$45 per m² |
| Concrete slab breaking | $400–$1,200 | |
| Waste removal | $200–$500 | |
| Foundation Work | Concrete piers | Included in most quotes |
| Extra-deep footings | +$800–$2,000 | |
| Rock drilling in limestone | +$500–$1,500 |
Structural Add-Ons
Many homeowners add railings, stairs and built-in features to a deck. These extras enhance usability, but they can quickly balloon the cost.
| Category | Item | Typical Cost |
| Railings and Balustrades | Timber rails | $150–$250 per linear metre |
| Aluminium or glass | $300–$500 per linear metre | |
| Wire cable systems | $250–$400 per linear metre | |
| Stairs | Basic three-step stairs | $600–$1,200 |
| Full staircase 1.5 m high | $1,500–$3,000 | |
| Curved or custom stairs | $3,000–$6,000 | |
| Built-In Features | Bench seating | $200–$400 per linear metre |
| Planter boxes | $300–$800 each | |
| Under-deck storage | $1,000–$2,500 |
Finishing and Protection
The harsh rays of the Perth sun, constant salty air, and winter rain mean that decks need a lot of protection from the beginning. Durable finishing can help decks to last a lifetime and look elegant.
| Protection Type | Typical Cost |
| Timber staining or sealing | $8–$15 per m² |
| UV-resistant coating | $10–$18 per m² |
| Marine-grade fixings | +$200–$500 |
| Waterproof membrane under deck | $15–$25 per m² |
Real Perth Deck Projects with Complete Costs
Here are some examples so you can see how the cost to install a decking are shaped by different factors:
Project #1 – Budget Deck in Baldivis
The clients asked for a basic barbecue area for cooking up weekend steaks with” no added features.
Specs
- 20 m² treated pine
- Ground level
- Easy flat access
- Standard suburban block
Complete Breakdown
- Treated pine boards: $1,000
- Structural framing: $600
- Galvanised fixings: $150
- Labour, 2.5 days: $3,000
- Staining: $300
- Council permit: $0
TOTAL: $5,050 ($253 per m²)
Timeline: 3 days
Project #2 – Premium Hardwood in Cottesloe
A coastal home needed a deck that would withstand salty air and the harsh sun while still complementing views of the ocean.
Specs
- 45 m² Merbau hardwood
- Elevated 800 mm
- Coastal exposure
- Built-in seating
Complete Breakdown
- Merbau decking boards: $3,800
- Hardwood substructure: $1,800
- Marine-grade stainless fixings: $650
- Built-in bench 3 m: $900
- Labour, six days at $550 per day: $3,300
- Pre-oiling and sealing: $675
- Council permit: $450
TOTAL: $11,575 ($465 per m²)
Timeline: 7 days
Project #3 – Low-Maintenance Composite in Ellenbrook
This family desired a contemporary space that required little maintenance and with balustrading safe enough for children.
Specs
- 30 m² NexGen composite
- Two levels
- Glass balustrade
- Integrated lighting
Complete Breakdown
- Composite boards: $5,400
- Aluminium frame: $1,800
- Concealed fixing system: $360
- Glass balustrade 8 m: $3,200
- LED deck lights 12 units: $1,200
- Labour, five days at $520 per day: $2,600
- Electrician for lighting: $450
- Council permit: $380
TOTAL: $15,390 ($513 per m²)
Timeline: 6 days
Conclusion
Using a deck estimator to figure out the costs aids in planning without any surprises. Measure your deck area first. Pick the material that fits your lifestyle. Obtain three detailed quotes from any licensed Perth builders. Leave a 15–20% buffer. If you are looking for outdoor carpentry experts to install a deck, contact Boda Building Group. Our experts have been serving Perth for over 15 years. We provide wood, hardwood & composite decks. We’ll handle complete design and permits. Hire us in February 2026, and get a free consultation, same-day quotes.
Disclaimer: All costs mentioned in this blog are estimates only and may vary based on site conditions, material selection, design complexity, location within Perth, and changes in market pricing.
