ACT Granny Flat Approval Summary & Requirements

To build a granny flat in the ACT, you must meet specific planning and building requirements. If your proposal meets all the criteria below, you can usually gain approval through a streamlined process.

  • Zoning: Property must be in a residential zone.
  • Minimum Lot Size: At least 500 m².
  • Granny Flat Size: 40–90 m² in floor area.
  • Owner Requirement: Only the owner of the main residence can own the granny flat.
  • Parking: At least one car parking space (not in the front zone).
  • Pedestrian Access: Clear, unobstructed access required.
  • Privacy & Solar Access: Maintain privacy and solar access for neighbours.
  • Setbacks: 3m from rear boundary, 1.5–3m from side boundaries.
  • Plot Ratio: Total built area (main house + granny flat) ≤ 50% of block.
  • Height: Single-storey, within building envelope.
  • Accessibility: Must comply with AS 4299 Adaptable Housing (Class C).
  • Water Sensitive Urban Design: Rainwater tank and water-saving features (40% reduction).
  • Private Open Space: Must provide private open space for occupants.
  • Building Materials: Compatible with neighbourhood.
  • Approval Process: Submit DA or CDC, notify neighbours, obtain building approval.