NSW granny flat rules checker

Free. Addresses are looked up with NSW Government planning services; nothing is stored by Plynth. Which controls apply to a site

Site

    From the LEP's Land Zoning Map or the s 10.7 certificate. The Housing SEPP provisions apply in R1 to R5; complying development in R1 to R4.

    Lot

    From the plan or the s 10.7 certificate, excluding the access laneway of a battle-axe lot. At least 450 m² for complying development.

    The boundary with the primary road, measured at the building line: 12 m to 900 m², 15 m to 1,500 m², 18 m above.

    Dwellings

    Is there a principal dwelling on the lot, or will one be built with the granny flat?

    A secondary dwelling exists in conjunction with a principal dwelling; both can be approved together (s 55).

    Are there any other dwellings on the lot?

    Only one principal dwelling and one secondary dwelling can share the lot (s 52(2)(a)).

    How will the granny flat relate to the house?

    A separate building or an extension: s 54(2) and Schedule 1 apply.

    To the outer face of the external walls, excluding parking. 60 m² unless the LEP permits more.

    Including attached garages and structures, to test the Schedule 1 cl 4(2) cap on both dwellings together.

    Only if the council LEP's secondary dwelling clause allows more than 60 m² for this lot (clause 5.4(9)).

    Constraints

    Is the lot, or a building on it, a heritage item?

    LEP schedule 5, the State Heritage Register, an interim heritage order or a draft listing; all on the s 10.7 certificate.

    Is the lot in a heritage conservation area?

    From the LEP's Heritage Map or the s 10.7 certificate, including a draft conservation area.

    Is the lot bush fire prone land?

    Land on the council's bush fire prone land map certified by the RFS; shown on the s 10.7 certificate.

    Is the building area rated BAL-40 or flame zone (BAL-FZ)?

    From a bush fire attack level assessment. Complying development is unavailable in BAL-40 and BAL-FZ (cl 1.19A).

    Is the lot a flood control lot?

    A lot to which flood-related development controls apply for dwelling houses, as stated on the s 10.7 certificate.

    Is the building site in a flood storage area, floodway, flow path, high hazard or high risk area?

    As certified by the council or a hydraulic engineer (s 58(1)).

    Is the lot environmentally sensitive land, or in a buffer, river front, ecologically sensitive or protected area?

    Areas an EPI identifies under those names (Codes SEPP cl 1.19(1)(e)); listed on the s 10.7 certificate.

    Does any other Codes SEPP exclusion apply (critical habitat, wilderness, reserved land, acid sulfate soils class 1 or 2, contaminated land, biobanking, coastal hazard, foreshore, ANEF 25 contour, drinking water catchment)?

    Codes SEPP cl 1.17A and cl 1.19(1)(b) to (j); each appears on the s 10.7 certificate.

    Result

    Choose a zone, or look up an address, to start. Each test appears here with its clause as you answer, and the pathway updates as you go.

    Indicative only. A certifier or council decides; setbacks, height and site coverage are not tested, and the LEP, DCP and site constraints apply.

    Indicative only. The checker applies the Housing SEPP and Codes SEPP tests to your answers and to mapped data as a starting point; it does not test setbacks, height or site coverage, read the council's LEP and DCP, or confirm the BAL, flood or heritage status a certifier will rely on. A certifier or council decides, and site constraints, the LEP and the DCP apply. Nothing here is a guarantee of approval. Your answers stay in your browser; an address search goes to NSW planning services and is not stored; the share link carries your answers in its address only.

    What is a granny flat in NSW?

    In NSW a granny flat is a secondary dwelling: a self-contained dwelling established in conjunction with the principal dwelling, on the same lot, and either within, attached to or separate from it. The definition comes from the Standard Instrument LEP Dictionary, and every council LEP uses it. Because it is a dwelling in its own right, a studio without cooking facilities is not a secondary dwelling, and a second house on its own title is a dual occupancy or a subdivision, not a granny flat.

    Chapter 3, Part 1 of the State Environmental Planning Policy (Housing) 2021 is the State-wide granny flat legislation. It applies in Zones R1 to R5 wherever a dwelling house is permissible, allows a secondary dwelling with consent, caps its floor area at 60 m² unless the LEP allows more, requires that no other dwellings share the lot and forbids subdividing the two dwellings apart. Rural zones sit outside the Part: there the LEP's land use table and clause 5.5 decide.

    The two approval pathways

    The checker tells the pathways apart: a complying development certificate when every standard is met on land that is not excluded, otherwise a development application to council.

    1

    Complying development certificate

    A private certifier or council issues a complying development certificate (CDC) without a merit assessment when the proposal meets every standard in s 54 and Schedule 1 of the Housing SEPP and is not on excluded land. Zones R1 to R4 only, a lot of at least 450 m², a frontage of 12 to 18 m by lot size, 60 m² of floor area, 8.5 m height, the Schedule 1 setbacks and site coverage, and no heritage item, conservation area, BAL-40 or flame zone, floodway or other Codes SEPP exclusion.

    2

    Development application

    Where a standard is missed, the land is excluded from complying development, or the zone is R5, the proposal goes to council as a development application under s 52. Council must still refuse it if other dwellings would share the lot, the two dwellings together exceed the floor area allowed for a dwelling house, or the secondary dwelling exceeds 60 m² or the LEP's larger figure. Council then weighs the LEP, the DCP and the site under s 4.15 of the Act; 450 m² for a detached secondary dwelling is a non-discretionary standard, not a bar.

    Complying development standards by lot area

    Schedule 1 of the Housing SEPP sets the standards a certifier applies to a secondary dwelling attached to or separate from the house. The checker tests the lot area, frontage and floor areas; the rest need a site plan.

    Standard450 to 900 m²More than 900 to 1,500 m²More than 1,500 m²Provision
    Minimum lot area450 m²450 m²450 m²s 54(2)(c)
    Frontage at the building line12 m15 m18 mSch 1 cl 2(1)(b)
    Secondary dwelling floor area60 m²*60 m²*60 m²*Sch 1 cl 4(1)
    Both dwellings and attached structures330 m² (to 600 m²) or 380 m²430 m²430 m²Sch 1 cl 4(2)
    Site coverage50%40%30%Sch 1 cl 3
    Building height8.5 m8.5 m8.5 mSch 1 cl 6
    Primary road setbackNeighbours' average or 4.5 mNeighbours' average or 6.5 mNeighbours' average or 10 mSch 1 cl 7
    Side setback0.9 m1.5 m2.5 mSch 1 cl 9
    Rear setback3 m5 m10 mSch 1 cl 10

    *Or the larger floor area the LEP permits for a secondary dwelling (most LEPs adopt clause 5.4(9): the greater of 60 m² or a percentage of the principal dwelling). Side and rear setbacks grow with height above 3.8 m. Battle-axe lots need a 3 m laneway and a 12 m by 12 m lot behind it; a corner lot's secondary road setback is 2 to 5 m by lot size.

    What the checker does not test

    • The zone, lot area and mapped constraints come from NSW Government data as a starting point; the answers about dwellings, floor area, frontage, BAL, flood hazard and other exclusions are yours. Confirm each against the LEP, the DCP and the s 10.7 planning certificate.
    • Setbacks, building height, site coverage, parking, privacy and the Building Code of Australia are not tested. A certifier applies the full Schedule 1 and the Codes SEPP conditions to a site plan.
    • Council LEPs can permit a larger secondary dwelling under clause 5.4(9), and a non-standard instrument can use equivalent zones. Read the LEP that applies to the land.
    • Mapped layers show what is mapped, not what a certifier will find: bush fire prone land is not a BAL, a flood planning map is not a floodway certification, and heritage mapping lags draft items and interim orders.
    • An answer of "unsure" never counts as a pass. The complying result appears only when every test passes.

    Frequently asked questions

    What is a granny flat under NSW planning law?

    A granny flat is a secondary dwelling: a self-contained dwelling established in conjunction with the principal dwelling, on the same lot of land, and within, attached to or separate from it. The Standard Instrument LEP Dictionary sets that definition and the Housing SEPP applies it. A studio with no kitchen is not a secondary dwelling, and a second house on its own title is a dual occupancy or a subdivision.

    What are the NSW granny flat rules for complying development?

    Under s 54 and Schedule 1 of the Housing SEPP a secondary dwelling attached to or separate from the house is complying development in Zones R1 to R4 when the lot is at least 450 m² (excluding a battle-axe laneway), the frontage at the building line is at least 12 m for lots up to 900 m², 15 m up to 1,500 m² and 18 m above that, the secondary dwelling is no more than 60 m² unless the LEP allows more, the two dwellings and attached structures stay within 330, 380 or 430 m² by lot size, the building is no higher than 8.5 m, the setbacks and site coverage in Schedule 1 are met, only one principal and one secondary dwelling remain, there is no basement or roof terrace, and the land is not a heritage item, in a conservation area, in BAL-40 or the flame zone, in a floodway or on other land the Codes SEPP excludes.

    How big can a granny flat be in NSW?

    The Housing SEPP caps a secondary dwelling at 60 m² of floor area, or a larger area if another environmental planning instrument permits it (s 52(2)(c) and Schedule 1 cl 4(1)). Most council LEPs adopt clause 5.4(9) of the Standard Instrument, which allows the greater of 60 m² or a percentage of the principal dwelling's floor area, so a larger figure is possible where the LEP says so. For complying development the principal dwelling, secondary dwelling and attached ancillary structures together must also stay within 330 m² on a lot of 450 to 600 m², 380 m² up to 900 m² and 430 m² above that. Floor area is measured to the outer face of the external walls and excludes parking.

    Can I build a granny flat on a 450 m² block?

    A 450 m² lot meets the minimum for complying development (s 54(2)(c)) and the 450 m² non-discretionary standard for a detached secondary dwelling in a development application (s 53(2)(a)). It still needs a 12 m frontage at the building line, a 50% site coverage limit, the Schedule 1 setbacks and no excluded-land trigger. Below 450 m² complying development is not available for an attached or detached secondary dwelling, though a development application can still be made and council keeps its discretion.

    Do I need a DA for a granny flat in NSW?

    Not always. A proposal that meets every Housing SEPP standard on land that is not excluded can be approved by a private certifier or council through a complying development certificate, usually in weeks. A proposal that misses a standard, sits on excluded land such as a heritage conservation area or flame zone, or is in Zone R5 needs a development application to council under s 52. Rural land is outside the Housing SEPP granny flat provisions altogether; the LEP decides whether a secondary dwelling is permitted there.

    Are granny flats allowed on rural land in NSW?

    The Housing SEPP's secondary dwelling provisions apply only in residential zones R1 to R5. In rural zones RU1 to RU6 a secondary dwelling is permitted only where the LEP's land use table lists it, usually with consent, and the Standard Instrument's optional clause 5.5 lets the LEP cap the floor area (a square-metre figure or a percentage of the principal dwelling) and the distance between the two dwellings. Read the LEP for the land.

    Can a granny flat be subdivided or strata titled?

    No. Section 51 of the Housing SEPP stops consent for the subdivision of a lot developed under its secondary dwelling provisions, and clause 2.6(2) of the Standard Instrument LEP stops a subdivision that would put the principal and secondary dwellings on separate lots unless each lot meets the minimum lot size on the Lot Size Map. A secondary dwelling stays on the same title as the house.

    What are the requirements for an unapproved granny flat in NSW?

    An unapproved granny flat is a secondary dwelling built or converted without a complying development certificate or development consent, or used in a way the approval did not cover. Council can issue orders about the building and its use. The Environmental Planning and Assessment Act 1979 gives owners, purchasers and people with the owner's consent a route for the building itself: a building information certificate under Division 6.7 (ss 6.22 to 6.26). Council issues one when there is no matter that would entitle it to order the building repaired, demolished, altered, added to or rebuilt, or when it does not propose to make such an order; the certificate then stops those orders for matters existing at its date and, for fair wear and tear, for seven years. Council can ask for plans, survey reports and certificates before deciding, and must give reasons if it refuses. A building information certificate does not authorise a use, so whether the dwelling can lawfully be occupied as a secondary dwelling is a separate question for council that usually needs development consent for the existing building and its use. Get advice from council or a certifier before buying or renting a property with an unapproved granny flat.

    Does a heritage conservation area stop a granny flat?

    It stops the complying development pathway, not the granny flat. Clause 1.19(1)(a) of the Codes SEPP excludes land in a heritage conservation area or draft conservation area from complying development for a secondary dwelling, and clause 1.17A(1)(d) excludes heritage items. A development application to council remains open, and the LEP's heritage clause (usually clause 5.10) sets what council considers.

    Can I build a granny flat on bushfire prone land?

    Often, but not in the worst-rated part of it. Complying development cannot be carried out on land in bush fire attack level 40 (BAL-40) or the flame zone (BAL-FZ) (Codes SEPP cl 1.19A; Housing SEPP s 57(1)(b)). On other bush fire prone land a complying secondary dwelling must conform to Planning for Bush Fire Protection and meet the s 57(2) standards for access, water supply and gas. The bush fire prone land map only tells you the lot is mapped; the BAL comes from a site assessment by council or an RFS-recognised consultant.

    What happens if my lot is flood affected?

    A flood control lot is one to which flood-related development controls apply for dwelling houses, a matter listed on the s 10.7 planning certificate. On such a lot, complying development cannot be carried out on a flood storage area, floodway, flow path, high hazard area or high risk area as certified by council or a hydraulic engineer (s 58(1)), and the dwelling must meet the s 58(2) standards for floor level, flood-compatible materials, structural resistance, refuge access and car parking. Elsewhere on the lot the complying pathway stays open.

    Is this checker a planning assessment?

    No. It applies the Housing SEPP and Codes SEPP tests to the answers you give and to NSW Government mapping for the address, and lists each test with the clause it follows. It does not test setbacks, height or site coverage, read the council's LEP or DCP, confirm a bushfire attack level, flood category or heritage status, or apply local variations. A certifier or council decides. Treat the result as a starting point for a conversation with them.

    Where does the address lookup get its data?

    From NSW Government services. The NSW Planning Portal's address search finds the property, its planning-layer query returns the zone and the lot boundaries, the NSW cadastre supplies the registered lot areas, and the Planning Portal's map services are queried with the lot boundary for heritage items and conservation areas, the State Heritage Register, bush fire prone land, the flood planning map, environmentally sensitive land, acid sulfate soils, minimum lot size and Codes SEPP exclusion areas. Plynth's server relays each request and caches the answer for about a day; the address is not stored or logged. Contains NSW Government data, CC BY 4.0.

    Sources

    State Environmental Planning Policy (Housing) 2021 and State Environmental Planning Policy (Exempt and Complying Development Codes) 2008, current versions for 11 September 2026 to date; Standard Instrument (Local Environmental Plans) Order 2006, current version for 1 July 2026 to date. Read on the NSW legislation website on 26 September 2026. Council LEPs adopt the Standard Instrument clauses with their own maps and local figures.

    Address lookup data

    Contains NSW Government data from the NSW Planning Portal and NSW Spatial Services, CC BY 4.0. Plynth's server relays each lookup and caches the answer for about a day; addresses are not stored or logged.

    The granny flat rules are one question.
    The site has a hundred more.

    Plynth answers site questions with every control linked to its source: the zone, the mapped constraints, the written clause and the other standards that apply to the same parcel.