New South Wales · Planning guide
Dual occupancy rules in NSW
A dual occupancy in NSW is two dwellings on one lot, attached or detached, and it is not a secondary dwelling. Whether it is permitted depends first on your zone in the council's LEP, and since 2025 the Housing SEPP also permits dual occupancies with consent in Zone R2 across most of the state. In a low and mid rise housing area the SEPP sets non-discretionary standards including a 450m² minimum lot size, and the Codes SEPP offers a complying development route on lots of at least 400m².
Sources read on 9 September 2026. Provisions are quoted word for word from the instrument.
What a dual occupancy is
The Standard Instrument defines a dual occupancy in two forms. A dual occupancy (attached) is 2 dwellings on one lot of land that are attached to each other. A dual occupancy (detached) is 2 detached dwellings on one lot. Both definitions carry the same exclusion: a secondary dwelling is not a dual occupancy. A duplex is the everyday name for the attached form.
The distinction from a granny flat matters because the rules are different. A secondary dwelling is subordinate to a principal dwelling and cannot be subdivided off. A dual occupancy is two dwellings of equal standing, each capable in principle of its own title, and it is assessed against the zone's dual occupancy permissibility rather than the Housing SEPP's secondary dwelling Part.
Semi-detached dwellings are a third, separate term. A semi-detached dwelling is on its own lot and attached to only one other dwelling. A dual occupancy that is later Torrens subdivided ends up as two semi-detached or two detached dwellings on two lots, which is why the subdivision rules deserve their own reading.
dual occupancy (attached) means 2 dwellings on one lot of land that are attached to each other, but does not include a secondary dwelling. Note. Dual occupancies (attached) are a type of dual occupancy —see the definition of that term in this Dictionary. dual occupancy (detached) means 2 detached dwellings on one lot of land, but does not include a secondary dwelling.
Read the source · retrieved 9 September 2026
secondary dwelling means a self-contained dwelling that— (a) is established in conjunction with another dwelling (the principal dwelling), and (b) is on the same lot of land as the principal dwelling, and (c) is located within, or is attached to, or is separate from, the principal dwelling.
Read the source · retrieved 9 September 2026
Permissibility starts with the zone table
Every LEP made under the Standard Instrument contains a Land Use Table that lists, for each zone, what is permitted without consent, what is permitted with consent and what is prohibited. The consent authority must have regard to the zone objectives when it determines an application. Dual occupancies appear in that table only where the council chose to put them.
The Standard Instrument's Zone R2 Low Density Residential template shows how much is left to the council. The mandatory content is short: roads, and a list that includes dwelling houses, group homes and child care facilities. Dual occupancies are not in the mandatory list, so whether a council permits dual occupancy in R2, and whether it permits both attached and detached forms, is a council decision written into its own LEP.
That is why two neighbouring councils can give opposite answers on identical blocks. Read the Land Use Table for your zone in your council's LEP first. If dual occupancies are listed under permitted with consent, the use is available and a development application is the standard route. If they are not listed, the next section is the one that may change the answer.
The consent authority must have regard to the objectives for development in a zone when determining a development application in respect of land within the zone.
Read the source · retrieved 9 September 2026
Direction. The following must be permitted with or without development consent in this zone— Roads 1 Objectives of zone • To provide for the housing needs of the community within a low density residential environment. • To enable other land uses that provide facilities or services to meet the day to day needs of residents. 2 Permitted without consent Home occupations 3 Permitted with consent Centre-based child care facilities; Dwelling houses; Group homes; Oyster aquaculture; Pond-based aquaculture; Respite day care centres; Tank-based aquaculture 4 Prohibited
Read the source · retrieved 9 September 2026
Chapter 6 of the Housing SEPP: dual occupancies in Zone R2
In 2025 the Housing SEPP gained Chapter 6, Low and mid rise housing. Section 166 permits dual occupancies and semi-detached dwellings with development consent in Zone R2 Low Density Residential on land to which the chapter applies. This operates despite the council's Land Use Table, so it adds the use in R2 zones where the LEP was silent or prohibited it.
The chapter does not apply everywhere. Section 164 excludes bush fire prone land, coastal vulnerability and coastal wetland land, land covered by Chapter 5, heritage items, a list of named regional local government areas, land near certain pipelines and airports, accelerated transport oriented development precincts and any land shown on the Low and Mid Rise Housing Exclusion Map. If your parcel falls in any of these, section 166 does not reach it and the LEP alone governs.
A second layer applies only inside a low and mid rise housing area, defined as land within 800m walking distance of a mapped Town Centre or a listed railway, metro or light rail station. Inside those areas section 168 sets non-discretionary standards for dual occupancies in Zones R1 to R4: a minimum lot size of 450m², a minimum lot width of 12m at the front building line, a maximum floor space ratio of 0.65:1 and a maximum building height of 9.5m. A council cannot refuse on those matters if the standards are met.
Development for the purposes of dual occupancies or semi-detached dwellings is permitted with development consent on land to which this chapter applies in Zone R2 Low Density Residential.
Read the source · retrieved 9 September 2026
This chapter applies to the whole of the State, other than the following— (a) bush fire prone land, (b) land identified as a coastal vulnerability area or a coastal wetlands and littoral rainforests area within the meaning of State Environmental Planning Policy (Resilience and Hazards) 2021, Chapter 2, (c) land to which Chapter 5 applies, (d) land that is a heritage item or on which a heritage item is located,
Read the source · retrieved 9 September 2026
low and mid rise housing area means— (a) land within 800m walking distance of— (i) land identified as “Town Centre” on the Town Centres Map, or (ii) a public entrance to a railway, metro or light rail station listed in Schedule 11, or (iii) for a light rail station listed in Schedule 11 with no public entrance—a platform of the light rail station, and (b) if a site area contains land identified in paragraph (a)—the site area.
Read the source · retrieved 9 September 2026
(1) This section applies to development for the purposes of dual occupancies in a low and mid rise housing area in the following zones— (a) Zone R1 General Residential, (b) Zone R2 Low Density Residential, (c) Zone R3 Medium Density Residential, (d) Zone R4 High Density Residential. (2) The following non-discretionary development standards apply— (a) a minimum lot size of 450m², (b) a minimum lot width at the front building line of 12m, (c) if no environmental planning instrument or development control plan that applies to the land specifies a maximum number of car parking spaces per dwelling—a minimum of 1 car parking space per dwelling, (d) a maximum floor space ratio of 0.65:1, (e) a maximum building height of 9.5m.
Read the source · retrieved 9 September 2026
The complying development route
The Low Rise Housing Diversity Code in Part 3B of the Codes SEPP lets a 1 or 2 storey dual occupancy be approved as complying development, including the conversion of an existing dwelling into a dual occupancy. The lot must be in Zone RU5, R1, R2 or R3 and must have lawful access to a public road when the work is finished.
Complying development never makes a use permissible. Clause 1.18 of the Codes SEPP requires the development to be permissible with consent under an instrument applying to the land, so the zone table or Chapter 6 test above must be passed first. The code then adds its own built form standards.
Under clause 3B.8 the parent lot must be at least 400m² or the minimum dual occupancy lot area in the applicable instrument, whichever is greater, and at least 12m or 15m wide at the building line depending on where the car parking is accessed. Height is capped at 8.5m above existing ground by clause 3B.9, and clause 3B.15 requires landscaped area of 50% of the parent lot area minus 100m², with at least 25% of the area forward of the building line landscaped.
The following types of development are complying development under this code— (a) the erection or alteration of, or addition to— (i) any 1 or 2 storey dual occupancy, manor house or multi dwelling housing (terraces), or (ii) any attached development or detached development related to any building referred to in subparagraph (i), (b) the conversion of an existing dwelling to a dual occupancy.
Read the source · retrieved 9 September 2026
Lot requirements Complying development specified for this code may only be carried out on a lot that meets the following requirements— (a) the lot must be in Zone RU5, Zone R1, Zone R2 or Zone R3, (b) the lot must have lawful access to a public road at the completion of the development.
Read the source · retrieved 9 September 2026
To be complying development for the purposes of this Policy, the development must— (a) not be exempt development under this Policy, and (b) be permissible, with consent, under an environmental planning instrument applying to the land on which the development is carried out, and (c) meet the relevant provisions of the Building Code of Australia, and
Read the source · retrieved 9 September 2026
The area of the parent lot must not be less than whichever is the greater of the following— (a) 400m², (b) the minimum lot area specified for dual occupancies in the environmental planning instrument, other than State Environmental Planning Policy (Housing) 2021, Chapter 6, Part 2, Division 2, that applies to the land concerned. (2) The width of the parent lot must not be less than the following when measured at the building line— (a) if the car parking space for the parent lot is accessed only from a secondary road, parallel road or lane—12m, (b) otherwise—15m.
Read the source · retrieved 9 September 2026
The maximum height for a dual occupancy and any attached development is 8.5m above ground level (existing).
Read the source · retrieved 9 September 2026
The minimum landscaped area that must be provided is 50% of the parent lot area minus 100m². (2) At least 25% of the area of the lot forward of the building line must be landscaped.
Read the source · retrieved 9 September 2026
Putting each dwelling on its own title
Building two dwellings and creating two titles are separate approvals. In a low and mid rise housing area, section 169 of the Housing SEPP sets non-discretionary standards for Torrens subdivision of a dual occupancy in Zones R1 to R3: one dwelling per resulting lot, each lot at least 6m wide at the front building line, lawful access and frontage to a public road, an area of at least 225m² and no battle-axe lots. The section applies only to dual occupancies consented on or after 28 February 2025, and it does not apply to strata subdivision.
Outside those areas the council's LEP governs. Many LEPs adopt a local clause that fixes a minimum lot size for dual occupancy subdivision, and the Codes SEPP subdivision code reads that figure in: clause 6.4 requires each resulting lot to be at least the minimum specified in the instrument, or 200m² if none is specified. Strata subdivision of a dual occupancy built under a complying development certificate is also available under clause 6.1.
The council's Lot Size Map under clause 4.1 of the LEP is the other control to check, because Torrens subdivision that requires consent must meet the minimum on that map unless a specific exception applies. The subdivision guide covers this in full.
The following non-discretionary development standards apply— (a) each resulting lot must contain no more than 1 dwelling, (b) each resulting lot must be at least 6m wide at the front building line, (c) each resulting lot must have lawful access and frontage to a public road, (d) each resulting lot must have an area of at least 225m², (e) each resulting lot must not be a battle-axe lot. (4) This section does not apply to strata subdivision.
Read the source · retrieved 9 September 2026
each resulting lot must be at least 6m wide (measured at the building line) and have lawful access, and frontage to, a public road, (d) if the subdivision relates to a dual occupancy, the area of each resulting lot must be at least— (i) the minimum size specified for the subdivision of land for the purpose of a dual occupancy in the environmental planning instrument that applies to the land, or that applied to the land at the relevant time, or (ii) if no minimum size is, or was at the relevant time, specified—200m²,
Read the source · retrieved 9 September 2026
The strata subdivision of a building for which development consent or a complying development certificate was granted or issued is, for 5 years from the date the consent or certificate was granted or issued, development specified for this code. (2) The strata subdivision of a dual occupancy, manor house or multi dwelling housing (terraces), for which a complying development certificate has been issued under the Low Rise Housing Diversity Code, is development specified for this code.
Read the source · retrieved 9 September 2026
What changes council by council in New South Wales
The state instruments set the frame. These points are set by each council's own instrument or mapping, so the answer for an address depends on which council it sits in.
- Whether dual occupancy (attached), dual occupancy (detached) or both are permitted with consent in each residential zone (the council's LEP Land Use Table).
- Any minimum lot size for a dual occupancy or for its subdivision, which the Codes SEPP and Housing SEPP both read in where one exists (a local clause in the council's LEP).
- The building height, floor space ratio and lot size shown on the LEP maps for the parcel (the council's Height of Buildings, Floor Space Ratio and Lot Size Maps).
- Setbacks, private open space, parking and design controls for a dual occupancy assessed by development application (the council's Development Control Plan).
- Whether the parcel is on land excluded from Chapter 6 of the Housing SEPP, for example a heritage item, bush fire prone land or the Low and Mid Rise Housing Exclusion Map (LEP maps and state maps).
For your address
How the $150 report settles this for one site
A Casa preliminary planning report reads the zone, the mapped controls (lot size, height and floor space ratio) and the state policies that apply at that parcel, then states which pathway the rule set allows and cites the clause behind each answer. Where a control depends on a council map or a DCP the report says so and names the instrument, rather than filling the gap with a guess.
Common questions
Is a duplex the same as a dual occupancy in NSW?
Yes. A duplex is the common name for a dual occupancy (attached), which the Standard Instrument defines as 2 dwellings on one lot of land that are attached to each other. Two separate houses on one lot is a dual occupancy (detached).
Can I build a dual occupancy in an R2 zone?
Since 2025 section 166 of the Housing SEPP permits dual occupancies with development consent in Zone R2 on land to which Chapter 6 applies. The chapter excludes bush fire prone land, heritage items, named regional councils and mapped exclusion areas, so the parcel has to be checked against section 164 first. Outside the chapter, the council's LEP Land Use Table decides.
What lot size do I need for a dual occupancy?
There is no single state figure. In a low and mid rise housing area section 168 of the Housing SEPP sets a non-discretionary minimum of 450m². The Codes SEPP complying development route requires at least 400m² or the LEP minimum, whichever is greater. A council's LEP may set its own minimum through a local clause.
Can I build a dual occupancy without a DA?
The Low Rise Housing Diversity Code in Part 3B of the Codes SEPP allows a 1 or 2 storey dual occupancy as complying development in Zones RU5, R1, R2 and R3 if the use is permissible on the land and the lot and design standards are met, including the 8.5m height limit.
Can each half of a dual occupancy be sold separately?
Only after subdivision. In a low and mid rise housing area section 169 of the Housing SEPP sets standards for Torrens subdivision, including lots of at least 225m² and 6m wide. Elsewhere the LEP's minimum lot size for dual occupancy subdivision applies, and the Codes SEPP subdivision code reads that minimum in or uses 200m² where none is set.
Sources read for this guide
- Standard Instrument (Local Environmental Plans) Order 2006, current version for 1 July 2026 to date, NSW legislation websiteread 9 September 2026
- State Environmental Planning Policy (Housing) 2021, current version for 10 August 2026 to date, NSW legislation websiteread 9 September 2026
- State Environmental Planning Policy (Exempt and Complying Development Codes) 2008, current version for 8 July 2026 to date, NSW legislation websiteread 9 September 2026
Not covered here
- The full list of local government areas excluded from Chapter 6 of the Housing SEPP in section 164(1)(e) was read but not quoted in full, so the guide does not name each council.
- Whether any particular council's LEP permits dual occupancies in R2, and any local minimum lot size clause, was not checked. Those are council-by-council instruments.
- The Codes SEPP Part 3B setback and parking clauses (3B.11, 3B.18) were not quoted, so the complying development setbacks for a dual occupancy are not stated.
More NSW guides
- Granny flat rules in NSW
- Subdivision rules in NSW
- Exempt and complying development in NSW
- Height, setback and site coverage rules in NSW
- Do I need a DA in NSW?
Dual occupancy and duplex rules in other states
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