What are the Complying Development Standards under the NSW Codes SEPP for Dual Occupancies?

Key development controls for residential complying developments in NSW, focusing on dual occupancies.

All standards are drawn from the State Environmental Planning Policy (Exempt and Complying Development Codes) 2008 (Codes SEPP) specifically Low Rise Housing Diversity Code.

Local LEP/DCP standards are overridden by these state controls for complying development.

Development Type	Dual Occupancy (two dwellings)
Permissible Zones	R1, R2, R3, RU5 (only where LEP permits dual occ)
Min. Lot Size	As per LEP’s min lot size for dual occ; if none specified, 400 m² minimum (the Codes SEPP imposes 400 m² as a floor minimum). Each dual occ lot must meet this (i.e. 800 m² for Torrens subdivision of 2 equal lots).
Min. Lot Width	15 m at the building line (for street frontage). (May be reduced to 12 m if vehicular access is only from a rear lane, parallel road or secondary road).
Max. Number of Dwellings	2 dwellings per lot (dual occupancy can be attached side-by-side or one above the other, or detached, but no additional secondary dwellings).
Max. Building Height	8.5 m (max. 2 storeys) for dual occupancies. (Same height limit applies whether side-by-side or one-above configuration.)
Max. Number of Storeys	2 storeys (one or two storeys permitted). Dual occ (one above the other) is inherently 2 storeys; side-by-side can be single or double storey, but overall max 2.
Maximum Gross Floor Area (GFA) (All buildings on the lot)	Lot area ≤2000 m²: Max GFA = 25% of parent lot area + 300 m²; Lot >2000 m²: 800 m² cap. (This effectively allows up to roughly 0.5:1 floor space ratio on smaller lots. For example, on a 400 m² lot, max GFA ≈ 25%*400+300 = 400 m² total for both dwellings.)
Site Coverage / Landscaped Area	≥ 50% of the parent lot area must be landscaped, minus 100 m² (i.e. 0.5*(lot area) – 100 m²). Also, at least 25% of the front yard (area forward of the building line) must be landscaped, and ≥50% of the total required landscaped area should be behind the building line. (Landscaped areas must be min 1.5 m x 1.5 m in size.)
Front Setback (Primary road)	Match two nearest dwellings’ setback (within 40 m), or if none: use the lot-size defaults (3 m / 4.5 m / 6.5 m / 10 m as per above). Dual occupancies are usually in established areas so the average-neighbour setback rule applies. Both dwellings typically align as one building or separate buildings in line.  (On corner lots, one dwelling can face the side street with a secondary road setback of 2–3 m as applicable.)
Side Setbacks (Boundary clearance)	Side-by-side dual occ: Generally same side setback as a house – 0.9 m min (single storey) increasing for two-storey portions. One-above dual occ: Treated like a single building: the Code sets a slightly larger side setback. Minimum 1.5 m side boundary setback for any dual occupancy where one dwelling sits above the other (essentially a two-storey building). (For parts of such building that extend >10 m back from the front, and are >4.5 m high, an even greater side setback may be required e.g. an extra 0.5–1 m to protect rear neighbours.)
Rear Setback	Similar to a house: usually ≥ 3 m for single storey parts, and ≥ 6 m for two-storey parts on a typical lot. The Low Rise Code specifies a graduated rear setback based on lot size: for example, on 600–900 m² lots, minimum 3 m (1-storey) and 8 m (2-storey); on 900–1500 m² lots, 5 m (1-storey) and 12 m (2-storey); on >1500 m² lots, 10 m (1-storey) and 15 m (2-storey). These ensure larger developments leave substantial rear open space.
Private Open Space (Principal private open space for each dwelling)	Each dwelling must have its own private open space.  For ground-level dwellings (e.g. side-by-side dual occ), provide ≥16 m² at ground level with min 3 m width. In a dual occupancy where one unit is upstairs, that upper unit must have a balcony of ≥8 m² (if 1-bedroom) or ≥12 m² (if 2+ bedrooms), with min 3 m dimensions. Ground floor units in that scenario still require 16 m² yard space. All principal POS must be adjacent to a living area and behind the front building line.
Car Parking	At least 1 off-street parking space per dwelling is required. So a dual occupancy must have a minimum of 2 car spaces (tandem or side-by-side). These can be in the form of garages or hard-stand spaces. If strata subdivided, parking may be consolidated (e.g. a shared driveway), but each unit needs its own allocated space.
Additional Design Rules / Notes	– Street frontage requirement: Both dwellings in a dual occupancy must have a frontage to a public road (they cannot be one behind the other on an internal lot). On a corner lot or parallel road lot, each dwelling may face a different road, which is allowed. Battle-axe (flag) lots are excluded from the Dual Occ Code. – Subdivision: Torrens title subdivision of a dual occupancy is permitted concurrently with the CDC if the LEP allows subdivision of dual occupancies. Each new lot must meet the minimum lot size (e.g. ≥ 400 m² each or the LEP minimum). Strata subdivision is also permitted (each strata lot must be ≥180 m² for side-by-side dual occ). – Design Guide compliance: Dual occ developments must also satisfy the Low Rise Housing Diversity Design Guide (for solar access, privacy, landscaping, etc., e.g. 3 hours sunlight to living rooms and POS for 75% of dwellings). An accredited designer must verify the design meets these criteria. – Attached/Detached: Dual occupancies can be attached (sharing a party wall or floor) or detached; the Code treats both similarly aside from definition. – Parking layout: If two separate driveways are proposed, they must each be max 3 m wide and minimum 1 m apart to retain street trees (or a single combined driveway of max 6 m width) – per general complying dev rules.