What a deck costs in Melbourne

What drives the price

Boards, then height. Melbourne guides price a treated pine deck, built on new footings and subframe, at about $190 to $370 per square metre installed, merbau at $315 to $580, spotted gum or blackbutt at $370 to $630, and composite at $295 to $735, with capped premium composite higher again. Those rates include the bearers, joists, posts and fixings, and they move with board width, hidden fixings and how much cutting the shape needs.

Above 1 m off the ground the footings go deeper, the frame needs bracing and everything is done from a ladder, which Melbourne guides put at another $52 to $190 per square metre; a balustrade is required wherever someone could fall 1 m or more, at $150 to $470 per metre depending on timber-and-wire, aluminium or glass. Steps are priced each, and an old deck costs about $21 to $58 per square metre to demolish and cart away.

• Area, and the shape
• Boards: treated pine, merbau, spotted gum or blackbutt, composite
• Height off the ground, and whether it’s attached to the house
• Balustrade metres and type, and the number of steps
• Demolishing an old deck, and access for materials

Permits and the registered-builder threshold

The Building and Plumbing Commission says decks typically use a structural subfloor and need a building permit, and its practice note says a deck attached to a building needs one regardless of size. Timber slats laid straight onto concrete or soil aren’t treated as a deck, and councils treat a small freestanding deck low to the ground as possibly exempt; a registered building surveyor issues the permit and can tell you which case yours is. Your council can say whether a planning permit applies too, for example in a heritage overlay.

If the contract price is more than $10,000, which most decks are, the work needs a builder registered with the Building and Plumbing Commission and a major domestic building contract; the deposit can’t be more than 10% under $20,000 or 5% from $20,000, and contracts over $20,000 signed from 1 July 2026 need Home Warranty insurance. The decks guide has the balustrade rules and the signs an old deck is failing.

What the quote should cover

• Design and documentation, and who applies for the permit
• Footings, subfloor (posts, bearers and joists) and the decking boards: material, grade and size
• Stairs, and balustrades built to the building code’s height rules
• Fixings suited to outdoor use, hidden or face-fixed
• Oiling, staining or sealing, or a note that it’s excluded
• Removing the old deck, and disposal
• Before You Dig Australia before footings go in

Example brief

“New 6 m × 4 m merbau deck attached to the back of a weatherboard house in Noble Park, about 60 cm off the ground, with three steps down to the lawn. The old 1990s pine deck needs removing. Please quote demolition, footings and subframe, boards and fixings, the steps, oiling, and arranging the building permit.”

Before you ask for quotes

• Measure the area and the height from ground to the finished floor
• Choose the boards, and decide on hidden or face fixings
• Count the balustrade metres if the deck is 1 m or more up
• Expect a permit for anything attached to the house
• Compare quotes on footings, subframe timber and fixings, not just boards

The estimator’s Get quotes button carries your details into the job form as a draft. You can also start a job request from scratch, read the decks guide, or compare the written quotes once they arrive. Availability depends on real postings, and registration must be enabled to submit.

How this estimate is built

Each line multiplies a per-unit range from the named sources by the quantity you entered, fixed items are added as their own lines, and the total is widened to round numbers. The sources were checked on 2 November 2026. It is an indicative range for comparing written quotes from a carpenter who has seen the job, not a quote. See all cost guides for how the ranges are made.