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R40 (WA R-Code)

R40 is a Western Australian R-Code density of roughly 40 dwellings per hectare. Minimum lot, plot ratio, and where it sits in the R-Codes density ladder.

By Chalkline. Last updated 28 May 2026. Verified 28 May 2026.

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R40 is one of the density codes in the WA Residential Design Codes (SPP 7.3), sitting between R30 (standard suburban) and R60 (urban grouped/multiple) in the density ladder R10, R20, R25, R30, R40, R60, R80, R100, R160, R200+. The number approximates the minimum density, around 40 dwellings per hectare, for the zone the council has coded R40 in its Local Planning Scheme map (verified 2026-05-28, per the live SPP 7.3 R-Codes article).

What R40 means on a lot

  • Minimum lot size: approximately 220 to 280 m² for a grouped dwelling, set by the R-Codes Volume 1 table for R40 (verified via live compliance/spp-7-3-r-codes).
  • Plot ratio: about 0.6 for grouped and multiple dwellings, per the WA plot ratio controls in R-Codes Volume 1 Part C. So a 600 m² R40 lot has a maximum gross floor area around 360 m² across the grouped dwellings on it.
  • Reduced setbacks compared with lower-density codes, and grouped or multiple dwellings are typically permitted on smaller lots than R30 would allow.

The R-Codes are read into every WA Local Planning Scheme, so the same R40 rules apply across the state, with any specific overlays the council has added in its scheme.

Where R40 is common

R40 is the higher-density suburban code. It is widely used in inner-suburban Perth, around town centres, and transit corridors where the WA Planning Commission and councils have rezoned to push more grouped and multiple dwellings onto smaller lots. A typical R40 lot in metropolitan Perth is a brownfield infill suited to two or three grouped dwellings rather than a single house.

Why it matters

The R-code is the first thing to confirm on a WA residential job, before any design starts. The R40 designation drives lot size, plot ratio, setbacks, and what types of dwelling (single, grouped, multiple) are permitted. Build to a lower-density code’s rules on an R40 lot and capacity is left on the table; build to a higher-density code’s rules and the development will not comply.

Also known as: R40 density, R40 zone.

Category: Planning / WA R-Codes

See also

Last updated: 2026-05-28. Verified: 2026-05-28. Quarterly review for currency.

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