How Much Does Decking Cost Per Square Metre in Perth?

These ranges generally assume uncomplicated residential work. Do not assume demolition, substantial excavation, stairs, balustrades, roofing or approvals are included.

We recommend using the figures to establish an early budget, then having the actual design and site assessed.

What Does “Per Square Metre Installed” Include?

Decking area is measured in square metres. For a rectangular deck, multiply its length by its width.

For example:

5 metres × 4 metres = 20m²

However, a price per square metre only becomes useful when you know what it covers.

A complete new deck may require:

• Site preparation.
• Footings and posts.
• Bearers and joists.
• Decking boards.
• Screws, clips and connectors.
• Fascia and edge finishing.
• Installation labour.
• Initial timber coating, where specified.
• Delivery and cleanup.

Some advertised prices cover boards only. Others cover laying new boards over an existing frame. Neither should be compared directly with a complete new deck.

At Skyline Concepts, we recommend establishing the scope first. The same 20m² area can represent very different amounts of construction work.



How Much Does a 10m², 20m² or 30m² Deck Cost?

Using a broad allowance of $300–$600 per square metre, the initial calculations are:

These are budgeting calculations, not quotes. They exclude separately priced extras, and small or complicated projects may fall outside the range.

For instance, a 20m² deck calculated at $450 per square metre produces a base allowance of $9,000. If the quote excludes removing the old deck, adding stairs and installing screening, those items need to be added.

We also recommend checking whether GST is included before comparing totals.

Timber vs Composite Decking Costs

Your choice of decking material affects both the construction budget and future maintenance.

Treated Pine Decking

Treated pine can offer a lower initial material cost than many hardwood or composite options.

However, the correct timber specification matters. Decking boards, framing and posts may have different exposure conditions and treatment requirements.

We recommend assessing the whole system rather than choosing timber solely on its price. Finishing, maintenance and suitability for the location should all form part of the decision.

Hardwood Timber Decking

Hardwood appeals to homeowners who want natural grain, colour variation and the feel of real timber.

The price varies between species and board sizes. Availability, timber grade, fixing requirements and preparation can also affect the installed cost.

We recommend confirming whether the quote includes the initial preparation and coating. A supplied-and-fixed timber deck may still need finishing before it is ready for its intended exposure.

Composite Decking

Composite decking includes a wide range of products with different finishes, profiles and installation requirements.

Its initial price can be higher than some timber options, but it generally avoids the routine oiling associated with maintaining a coated timber appearance.

Composite still requires cleaning and care. It should not be treated as maintenance-free.

We recommend comparing the complete installed system, including the required framing, clips, edge boards and finishing details.

Premium Manufactured Decking

Premium ranges can include different constructions and surface technologies, rather than simply being more expensive versions of the same board.

Check the exact product specification, care requirements and warranty terms.

A premium finish may be worthwhile for a prominent entertaining area, but the board choice should suit the location and expected use.

What Affects Decking Installation Costs in Perth?

1. The Supporting Frame

The subframe is one of the most important parts of the deck, even though it is largely hidden.

Posts, bearers, joists, connections and footings need to suit the design and conditions. The selected decking product also influences the support arrangement.

We recommend agreeing on the framing specification before comparing board prices.

Installing expensive boards over an unsuitable frame can create movement, unevenness and premature repair work. A well-finished surface depends on what supports it.

2. Deck Height

A deck close to the ground and an elevated deck have different construction requirements.

Raised structures may require longer posts, additional bracing, stairs, balustrades and more involved structural documentation.

Low decks can also be challenging. Limited space beneath the boards may complicate drainage, ventilation and access for installation.

We recommend assessing the available height at doorways and around the perimeter before settling on a design.

3. Ground Conditions and Footings

Excavation costs depend on what is beneath the surface.

Rock, buried concrete, roots, uncontrolled fill and existing services can affect footing locations and installation time.

We recommend checking how the quote treats unexpected conditions. It should be clear whether additional excavation is included or would require an agreed variation.

Correct foundations are part of the deck’s structure, so reducing them below the appropriate design is not a sensible saving.

4. Site Access

Easy access helps materials, equipment and waste move efficiently.

A backyard reached through a narrow passage or several flights of stairs can involve considerably more handling than an area beside a driveway.

We recommend showing the access route when requesting a quote. Photos of side gates, steps and parking arrangements can help identify potential constraints early.

5. Deck Shape and Board Layout

Simple rectangular layouts are generally more straightforward to construct.

Curves, angled boundaries, diagonal boards, multiple levels and detailed borders can increase labour and material waste.

A picture-frame border, for example, requires more than changing the direction of a few boards. It can involve additional framing and careful junction detailing.

We recommend choosing the layout before ordering materials so the quantities reflect how the deck will actually be built.

6. Cutting and Material Waste

The finished deck area is not necessarily the same as the quantity of boards purchased.

Available board lengths, layout and perimeter details influence offcuts. A design that looks efficient on paper may create substantial waste if it does not suit the supplied lengths.

We recommend asking for the proposed board direction and joint arrangement to be considered during quoting.

7. Removing an Existing Deck

Replacement projects need to account for dismantling and disposal.

Costs can include removing boards, framing, posts, footings and attached features. Restricted access can make the work more time-consuming.

Do not assume the old frame can be reused because the surface appears level.

At Skyline Concepts, we recommend assessing the structure before deciding whether replacement boards alone are appropriate.

8. Stairs, Landings and Balustrades

These features can add significantly to a project, particularly where there are multiple access points or changes in level.

Their cost depends on dimensions, materials, supporting structure and applicable safety requirements.

We recommend having them clearly described in the quote rather than assuming they form part of the deck’s square-metre rate.

9. Built-In Seating, Screens and Planters

Custom features can make a deck more useful and improve the way it connects with the garden.

They also require additional materials, support and finishing.

For built-in seating, consider how people will use the area and whether furniture could offer more flexibility. For planters, consider moisture management, drainage and maintenance access.

We recommend planning these features with the deck rather than adding them after construction.

10. Connections to the House

Door thresholds, wall junctions and existing drainage can influence the design.

The deck needs to meet the home at an appropriate level without obstructing required openings, inspection access or water management details.

We recommend resolving these junctions before construction. Making a deck appear flush with an internal floor should never take priority over a suitable building detail.

11. Lighting, Power and Services

Deck lighting, power points and outdoor kitchen services add work beyond the carpentry itself.

Licensed trades may need to install or relocate electrical, plumbing or gas services.

We recommend identifying these requirements early so the work can be coordinated before access beneath the deck becomes restricted.

12. Initial Finishing

For timber, preparation and coating can affect the final price.

Check whether the proposed work includes the specified preparation, coating products and application, or whether it stops at installing the boards.

Composite systems also need completed edges and suitable finishing components.

We recommend comparing quotes for the same finished result, not simply the same surface material.

Does Decking Over Concrete Cost Less?

It can reduce some work, but an existing slab does not automatically create a cheaper installation.

The assessment needs to consider:

• Available height beneath doors.
• Slab condition and falls.
• Drainage beneath the deck.
• Suitable framing and fixings.
• Ventilation.
• Access to drains and services.

A slab with insufficient clearance or poor drainage can require a more involved solution.

We recommend assessing the space between the existing surface and intended deck level before choosing the decking system.

What Makes Perth Decking Projects Different?

Strong Sun and Exposed Areas

Consider how the deck will be used during summer, particularly in uncovered areas.

Board colour, product characteristics and shade influence comfort. We recommend viewing physical samples and discussing exposure rather than choosing entirely from photographs.

A material that suits a sheltered alfresco may feel different on an exposed west-facing deck.

Coastal Locations

Homes near the coast need appropriate consideration of salt exposure and the suitability of fixings, connectors and framing.

We recommend checking the complete system for the location. The durability of the boards alone does not determine the durability of the deck.

Bushfire-Prone Properties

Where bushfire requirements apply, they can influence materials and construction details.

Do not assume a decking product is suitable based only on a general description such as “fire-resistant”.

We recommend confirming the project requirements and relevant product evidence before ordering.

Poolside Decks

Decks beside pools need careful attention to wet use, drainage, cleaning and the relationship with the pool barrier.

Raising the surface near a pool fence can change its effective height or create access issues.

We recommend planning the decking and pool fencing together.

Do You Need Council Approval for a Deck in Perth?

The answer depends on the property and proposed design.

Planning approval and a building permit are separate considerations. Deck area, height, boundary position, privacy screens and bushfire conditions can affect the approval pathway.

We recommend checking with the relevant local government before construction. Advice applying to one Perth property should not be assumed to cover another.

Include any required drawings, engineering, assessments and application fees in the project budget. A low deck should not automatically be treated as exempt from all requirements.

Can You Save Money by Reusing the Existing Frame?

Possibly, but only after assessment.

The frame needs to be structurally sound and compatible with the replacement boards. Different products can require different support spacing and fixing arrangements.

We recommend checking:

• Posts and footings.
• Bearers and joists.
• Connections and bracing.
• Deterioration or pest damage.
• Ground clearance and ventilation.
• Compatibility with the proposed boards.

Replacing the surface alone can be economical where the structure is suitable. Where substantial changes are needed, rebuilding may offer better value.

At Skyline Concepts, we recommend comparing the complete scope. Two quotes using the same decking brand can still describe very different structures and finishes.

How to Reduce Decking Costs Without Cutting Corners

Useful savings often come from a more efficient design.

Consider keeping the shape straightforward, selecting dimensions that work with available board lengths and limiting unnecessary changes in level.

Finalise lighting, stairs and custom features before construction to reduce alterations later.

We recommend prioritising suitable foundations, framing and fixings. Decorative details can be simplified, but the supporting structure needs to suit the project.

For uncertain replacement work, discuss whether a contingency allowance is appropriate before demolition begins.

Frequently Asked Questions

How Much Does a 20m² Deck Cost in Perth?

Using a broad allowance of $300–$600 per square metre, a 20m² deck calculates to $6,000–$12,000. This is an initial budget only; site preparation, premium products and additional features can change the total.

Is Composite Decking More Expensive Than Timber?

It can cost more initially than basic treated pine or some hardwood options. However, the comparison depends on the selected products, frame, installation and finishing. Consider ongoing maintenance as well as the upfront price.

Why Is a Small Deck More Expensive Per Square Metre?

Design, delivery, equipment setup and other fixed costs are spread across fewer square metres. Small decks can also have a high proportion of edges, steps or difficult junctions relative to their area.

Does a Decking Quote Include a Roof or Pergola?

Do not assume so. A deck, patio roof and pergola are different structures. Each needs to be included in the agreed scope.

Can I Buy the Boards and Pay for Installation Only?

That arrangement needs to be agreed with the installer first. Product suitability, quantities, delivery, storage and responsibility for damaged or missing materials should be resolved before purchasing.

Will a New Deck Add Value to My Home?

A well-designed deck can improve outdoor living and appeal to buyers, but there is no guaranteed return. We recommend designing it around practical use, a suitable budget and the character of the property.

Get a Decking Quote From Skyline Concepts

The cost of decking in Perth depends on the complete structure, not just the boards. Materials, framing, site conditions and finishing all contribute to the final result.

Contact our team to discuss your preferred decking, project dimensions and site conditions, and arrange a tailored quote.