Every South East Queensland council except Toowoomba caps how big a secondary dwelling can be before it needs a planning application, and the cap is measured as gross floor area. On a typical 600 m² suburban lot it runs from 45 m² in Moreton Bay to 85 m² in Redland, with Brisbane and the Gold Coast at 80, Logan and Lockyer Valley at 70, Noosa at 65 and Ipswich, Scenic Rim, Somerset and the Sunshine Coast at 60. Most councils lift the cap on bigger lots and in rural zones, up to 160 m² in Redland's rural zone on 6,000 m² or more. Over the cap the home is still possible, but it becomes a planning application assessed by council instead of a building approval alone.
The caps, with the step-ups
| Council | Typical lot | Bigger lot or rural zone |
|---|---|---|
| Brisbane | 80 m² | 80 m², within 20 m of the house |
| Moreton Bay | 45 m² on 450 to 800 m² | 55 m² over 800 m²; 100 m² in Rural and Rural residential |
| Logan | 70 m² under 1,000 m² | 100 m² on 1,000 m² or more |
| Ipswich | 60 m² on 450 to 600 m² | 90 m² over 600 m²; 120 m² over 800 m² |
| Redland | 85 m² under 1,000 m² | 112 m² on 1,000 m² or more; 160 m² in the Rural zone on 6,000 m² or more |
| Gold Coast | 80 m² | 80 m²; over that it is charged and assessed as a second dwelling |
| Sunshine Coast | 60 m² (45 m² around Moffat, Shelly and Dicky Beach) | 90 m² in Rural and Rural residential |
| Noosa | 65 m², two bedrooms at most | The same on any lot size, acreage included |
| Scenic Rim | 60 m² | 60 m² on any lot size |
| Lockyer Valley | 70 m² in residential and Township zones | 100 m² elsewhere, two bedrooms at most |
| Somerset | 60 m² under 2,000 m² | 90 m² on 2,000 m² or more; 120 m² on rural lots over 5 ha |
| Toowoomba | No cap | No cap; it must be subordinate to the house |
What gross floor area counts
Gross floor area is the floor inside the walls, so a 60 m² cap is a 60 m² home, not a 60 m² footprint with a deck on top. Noosa says in its fact sheet that unenclosed decks, balconies and garages do not count. Most schemes measure the same way, so a deck is the usual way to add outdoor room without touching the cap. A loft or second storey counts in full where the scheme allows one; Brisbane allows two storeys in most low density zones, Lockyer Valley and Somerset hold the height to 8.5 m.
What happens over the cap
The home stops being accepted development and becomes assessable: a planning application to council, usually code assessable against the dwelling house code, with a fee, a planner and time. In Redland the building application is referred to council before the certifier decides. On the Gold Coast a home over 80 m² is treated and charged as a second dwelling. In Toowoomba, with no cap, the test is whether the home is subordinate to the house, and council lists the signs it is not: its own driveway, letterbox, bins, meter or address. Over the cap is a path, not a wall, but it is the slower and dearer one.
Where the Housing Code fits
The Queensland Housing Code covers siting, not the cap. The cap stays in each council's planning scheme whether or not the council adopts the code. The Queensland Housing Code sets out the dates.
See it for your block
- Check your block: the cap for one address
- Council rules, with the scheme each cap was read from
- Homes that fit under each cap
Questions people ask next
What is the biggest granny flat allowed in South East Queensland?
On a typical lot, 85 m² in Redland without a planning application. On larger lots the caps rise: 112 m² in Redland on 1,000 m² or more and 160 m² in its rural zone, 120 m² in Ipswich over 800 m² and in Somerset's rural zone over 5 ha. Toowoomba sets no cap at all.
Does a deck count toward the size cap?
Usually not. The cap is gross floor area, the floor inside the walls. Noosa's fact sheet says unenclosed decks, balconies and garages are excluded, and most South East Queensland schemes measure the same way.
What if I want a home bigger than the cap?
It becomes a planning application to council instead of a building approval alone: code assessable in most councils, referred to council in Redland, and treated as a second dwelling on the Gold Coast. It is possible, with a fee, a planner and time.
- Brisbane City Plan 2014, dwelling house code, secondary dwelling, read 15 October 2026
- City of Moreton Bay, secondary dwelling information sheet, read 15 October 2026
- Logan Planning Scheme 2015, dual occupancy and dwelling house code, read 15 October 2026
- Ipswich Planning Scheme, dwelling house code, read 15 October 2026
- Redland City Council, amenity and aesthetics guideline, read 15 October 2026
- City of Gold Coast, City Plan, dwelling house code, read 15 October 2026
- Sunshine Coast Council, dwelling house code, read 15 October 2026
- Noosa Council, fact sheet 3, secondary dwellings, read 15 October 2026
- Scenic Rim Regional Council, dwelling houses and secondary dwellings fact sheet, read 15 October 2026
- Lockyer Valley Regional Council, dwelling houses and secondary dwellings info sheet, read 15 October 2026
- Somerset Region Planning Scheme, version 50, read 15 October 2026
- Toowoomba Region Planning Scheme, schedule 1 definitions, read 15 October 2026
- Queensland Government, secondary dwellings (council rules differ), read 16 October 2026