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Dual occupancy

Dual occupancy is two dwellings on one lot. Since 1 July 2024 the Housing SEPP permits them in R1-R4 zones state-wide: 450 m² lot, 12 m width, 9.5 m, FSR 0.65:1.

By Chalkline. Last updated 14 May 2026. Verified 14 May 2026.

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A dual occupancy is two separate dwellings on a single lot, either attached (a duplex sharing a common wall) or detached (two free-standing dwellings on the same lot). Each dwelling has its own kitchen, bathroom, and entry; the two units are equivalent rather than principal-plus-secondary. A dual occupancy is not a secondary dwelling (granny flat), which is one principal dwelling plus a smaller second unit.

NSW state-wide rules (Stage 1 reforms, from 1 July 2024). The Housing SEPP 2021 was amended on 1 July 2024 to permit dual occupancies and semi-detached dwellings in R1, R2, R3, and R4 residential zones state-wide, overriding any local LEP that previously prohibited them in R2 low-density zones. The state-wide standards are:

  • Minimum lot size: 450 m².
  • Minimum lot width: 12 m.
  • Maximum FSR (floor space ratio): 0.65:1.
  • Maximum building height: 9.5 m.

Subdivision back to two separate Torrens titles is permitted on R1, R2, and R3 lots if each resulting lot is at least 225 m² and at least 6 m wide.

The NSW state-wide override, explained. Before 1 July 2024, dual occupancy was permissible in NSW only where the local LEP’s land-use table listed it as permitted in that zone. Most R2 (low-density residential) zones across NSW did NOT list dual occupancy as permissible. The Stage 1 amendment to Housing SEPP 2021 makes dual occupancy permissible by force of the SEPP, regardless of what the LEP says. This is the SEPP-prevails-over-LEP rule in EP&A Act Section 3.28 doing real work: the SEPP unlocks a development pathway the LEP closes. Practically, a builder eyeing an R2 lot that the local LEP says is single-dwelling-only can now lodge for dual occupancy under the SEPP, provided the lot meets the 450 m² / 12 m / 9.5 m / 0.65:1 standards. Council can still impose DCP-level design controls (setbacks, parking, tree canopy), but it cannot prohibit the dual occupancy itself.

Stage 2 reforms (from 28 February 2025) layered additional low-rise and mid-rise housing forms (terraces, manor houses, low-rise flats) onto designated “low and mid-rise housing areas” near transport, with their own height and FSR parameters. Stage 2 sits on top of Stage 1; dual occupancy rules described above remain.

Other states. Dual occupancy permissions vary widely. In VIC, the equivalent concept is “two dwellings on a lot” under ResCode and the relevant council planning scheme. In QLD, dual occupancy is regulated locally under each council’s planning scheme. The NSW state-wide override is unusual in Australian planning law; check the local council instrument before assuming similar permissions elsewhere.

For builders. Dual occupancy is one of the largest residential-build volume opportunities post-reform. The compliance path runs through the LEP, the relevant DCP (council design controls still apply at design review), and the Housing SEPP for the headline standards. Setbacks, parking, and tree-canopy requirements still come from the council DCP.

Also known as: dual occ, duplex (attached), two-on-one.

Category: Approvals / planning / NSW.

See also

Last updated: 2026-05-14. Verified: 2026-05-14.

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