Decks: residential construction guide

Full guide

The complete residential deck guide is at Residential decks: framing, materials, and compliance. That article is the canonical reference on this topic. This stub exists as a shorter-slug entry point and will be retired in favour of a 301 redirect once the site supports it.

What the full article covers

The residential decks article covers:

• Framing to AS 1684.2 (non-cyclonic) and AS 1684.3 (cyclonic): footing types, post sizing, bearer and joist span tables
• Balustrade requirements under NCC 2022 Housing Provisions Part 11.3: minimum 1,000 mm height where fall exceeds 1 m, 125 mm sphere rule for openings
• Approval thresholds by state: NSW exempt development under SEPP 2008, Victoria building permit requirements, Queensland Building Act 1975 triggers
• Timber vs composite board options: merbau hardwood, H3 treated pine, Modwood and Trex composites
• Durability class and H3 treated timber requirements for external exposure
• Waling plate and ledger attachment to house framing per NCC 2022 Housing Provisions Part 12.3
• Flashing at deck-to-wall junction
• Tolerances and PCI acceptance criteria (deck surface, board gap, balustrade height and openings)
• Common holds: framing inspection before boarding, balustrade height measured after boards, post treatment grade, ledger flashing

Cost and compliance snapshot

Supply-and-install cost runs roughly $120 to $250/m2 for treated pine or merbau hardwood, and $250 to $450/m2 for composite, ex-GST (2026). A balustrade is required where there is a fall of 1 m or more to the surface below. Footing depth and size depends on soil classification and tributary load area.

See NCC 2022 Volume Two for the regulatory framework that governs Class 1 and 10 buildings including decks.

References

• Australian Building Codes Board (NCC)

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Canonical article: /practical/decks-residential. Last updated: 2026-05-10.