Can I extend my existing house and create a dual occupancy?

Yes, potentially. You may be able to extend or alter your existing house as part of creating a dual occupancy.

The completed development must provide two dwellings and meet the applicable dual occupancy (multi-unit housing) requirements. This includes requirements such as site coverage, setbacks, building height, private open space, planting, parking and access.

Whether this is possible will depend on the existing house, the block and whether the proposed development can meet the applicable planning and building requirements.

Reference: Planning (Missing Middle Housing) Design Guide 2026 - ACT Missing Middle Housing Design Guide & Territory Plan 2023 – Part E01 Residential Zone Policy -  Territory Plan 2023 | Notifiable instruments