Guide
Granny flat rules in NSW
Where the rules come from
Secondary dwellings are controlled by Chapter 3 of the State Environmental Planning Policy (Housing) 2021. The complying development standards are in Schedule 1 of that SEPP, and the general exclusions (heritage, flood, bushfire, environmentally sensitive land) come from the Codes SEPP, clauses 1.17A–1.19. NSW Planning’s plain-English summary is here.
Complying development standards
| Control | Lot 450–900 m² | Lot 900–1,500 m² | Lot over 1,500 m² |
|---|---|---|---|
| Frontage (Sch 1 cl 2) | 12 m | 15 m | 18 m |
| Side setback (cl 9) | 0.9 m | 1.5 m | 2.5 m |
| Rear setback (cl 10) | 3 m | 5 m | 10 m |
| Secondary road, corner lot (cl 7(3)) | 2 m to 600 m², then 3 m | 3 m | 5 m |
- Floor area: 60 m² for the secondary dwelling, or the LEP figure if larger.
- Height: 8.5 m above existing ground level.
- Taller buildings: side setbacks increase by 25% of the height above 3.8 m; rear setbacks by three times the height above 3.8 m. This is why two-storey flats are hard on smaller lots.
- Battle-axe lots: access handle at least 3 m wide and a 12 × 12 m building area, excluding the handle.
- Private open space (cl 17): more than 24 m², more than 4 m wide, no steeper than 1:50. It can be shared with the main house.
- Landscaped area (cl 16): to the Schedule’s standard, at least 2.5 m wide.
- Parking: no extra space required, but the lot must keep the spaces it had.
Always check the council’s LEP as well: it sets the zone, can permit a larger granny flat, and its minimum lot size still applies.
When you need a DA instead
- The lot is under 450 m², or the frontage is too narrow
- The property is a heritage item or in a heritage conservation area
- Flood or bushfire controls can’t be met under the code
- The design can’t meet a setback, height or open-space standard
A DA can still approve the flat — it is assessed on merit against the LEP and the council’s DCP. We refer DA work to PlanLand.
Other rules worth knowing
What is the maximum size of a granny flat in NSW?
Under the Housing SEPP a secondary dwelling can have up to 60 m² of floor area, or a larger area if the council’s LEP allows it. The lot’s total floor area cap also counts both dwellings and any attached garage, carport, deck, patio, pergola or verandah.
What is the minimum lot size for a granny flat in NSW?
To approve a granny flat as complying development (CDC), the lot generally needs to be at least 450 m². Smaller lots can still get approval through a development application (DA), assessed on merit.
Do I need council approval for a granny flat?
Not if it qualifies as complying development: a private certifier issues a CDC against fixed state standards. If it doesn’t qualify, you need a DA from council.
Can I subdivide a lot with a granny flat?
No. NSW Planning states that a lot on which a secondary dwelling is built cannot be subdivided.
Does a granny flat need its own parking space?
No. The Housing SEPP doesn’t require extra parking for a secondary dwelling, but a CDC must keep the same number of spaces the lot had before.
Can I Airbnb my granny flat in Sydney?
Yes, if you live on the property. NSW Planning says homeowners who live on a property with a granny flat can rent it out short-term 365 days a year. If you don’t live on site, non-hosted letting in Greater Sydney is capped at 180 days a year.
This guide summarises the controls as at the review date. It isn’t legal advice, and council LEPs vary. For a definite answer on your lot, use the free site check.
Can you build a granny flat on your block?
Send us the address. We check it against the NSW controls and tell you what fits, which pathway applies and what it will cost — free, within one business day.