Can I build a dual occupancy on a block smaller than 600 m²?
Yes, potentially. A dual occupancy may be possible on a block smaller than 600 m², as the current planning framework does not set 600 m² as a general minimum block size for dual occupancy.
However, the ACT Missing Middle Housing Design Guide identifies blocks greater than 600 m² as typically suited to dual occupancy. Therefore, while a smaller block is not necessarily excluded, it may be more challenging to achieve an appropriate design that meets all applicable planning requirements.
Reference: Planning (Missing Middle Housing) Design Guide 2026 – ACT Missing Middle Housing Design Guide
Short Answer
Yes, potentially. There is no general 600 m² minimum block-size requirement for dual occupancy. However, the Missing Middle Housing Design Guide identifies blocks over 600 m² as typically suited to dual occupancy, so development on a smaller block will depend on whether an appropriate compliant design can be achieved.
Detailed Explanation
Yes, potentially. The current planning framework does not prescribe 600 m² as a general statutory minimum block area for dual occupancy.
The ACT Missing Middle Housing Design Guide identifies “>600 sqm” as a block characteristic where dual occupancy is typically suited. This is design guidance rather than a prohibition on dual occupancy development below 600 m².
Accordingly, a proposal on a smaller block may still be considered where dual occupancy is a permitted land use and the development satisfies the applicable Territory Plan requirements.
No minimum block size does not remove the need for planning assessment.
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