The CDC benchmark: 450m² and 12m
Under the Low Rise Housing Diversity Code, a dual occupancy on an eligible R2/R3 lot commonly needs at least 450m² of area and a 12m frontage to pursue a CDC. Meet every standard and the fast-track is open.
Council LEP minimums can differ
For a DA, your council's LEP may set a different minimum lot size for dual occupancy, sometimes higher, occasionally with extra frontage or subdivision conditions. Two neighbouring councils can have quite different rules, which is why a rule of thumb is never enough.
When a smaller or narrower lot still works
Below the benchmark, a duplex isn't necessarily off the table, a considered DA design can sometimes succeed where the numbers are close and the design responds well to the street. Frontage under 12m calls for careful planning (see our narrow-block guide), but it's a design problem, not always a dead end.
Frequently asked questions
No, it's the common CDC benchmark under the Low Rise Housing Diversity Code. Councils set their own DA minimums in the LEP, so your specific site controls decide.
Authoritative sources: NSW Low Rise Housing Diversity Code, NSW Planning Portal.