Why Size Limits Vary
There is no single statewide size limit for secondary dwellings in Queensland. The State Government defines what a secondary dwelling is, but each local council determines how big it can be, where it can sit on your lot, and what approval pathway applies.
This means the same 54m² dwelling that sails through approval in one council area might require a development application in another — or might not be permitted at all in certain precincts.
The size limit for your property depends on three things: which council area you’re in, what zone your property is in (general residential, rural residential, rural, etc.), and sometimes the size of your lot or the width of your street frontage.
We’ve compiled the key figures for every major SEQ council below. Use this as a starting point — not a specification for your build.
Quick Reference Table
This table shows the maximum gross floor area (GFA) allowed for a secondary dwelling under each council’s planning scheme, broken down by zone type. GFA generally means the floor area measured to the outside of the walls, excluding patios, decks, carports and other non-habitable areas.
| Council | General Residential | Rural Residential | Rural Zone | Key Conditions |
|---|---|---|---|---|
| Brisbane | 80m² | 80m² | 100m² | Within 20m of primary dwelling. Min lot 600m² (or 450m² front lot). Site cover max 50%. |
| Moreton Bay | 45m² (lots ≤800m²) / 55m² (lots >800m²) | Up to 100m² | Up to 100m² | Within 10m in General Residential, 50m in Rural/Rural Res. Shared services required. Oct 2024 amendment tightened suburban rules. |
| Gold Coast | 80m² | 90m² | 90m² | Must be small in scale and clearly ancillary. Site cover max 50%. One additional car park required. |
| Logan | 70m² (lots <1,000m²) / 100m² (lots ≥1,000m²) | 100m² | 100m² | Within 20m of primary dwelling. Min lot 450m² with 15m frontage. Must be located behind primary dwelling. |
| Sunshine Coast | 60m² | 90m² | 90m² | Within 20m of primary dwelling. Min lot 600m² in urban zones. Caloundra South/coastal precincts: 45m² max, 4m height limit. |
| Ipswich | Up to ~80m² | Varies by zone | Varies by zone | Ipswich City Plan 2025 commenced 1 July 2025 and replaced the 2006 scheme. Secondary dwellings up to around 80m² are now supported, and council reports roughly 22,000 properties can add one without a development application. The old 50m² “auxiliary unit” cap no longer applies. |
| Redland | Under review | Under review | Under review | Amenity & Aesthetics Policy applies (from Feb 2024). Infrastructure charges may apply above certain thresholds. Major amendment 02/25 underway. |
| Noosa | 65m² | 65m² | 65m² | Max 2 bedrooms. One additional car park. Infrastructure charges may apply. |
| Scenic Rim | Varies by precinct | Varies | Varies | Check Scenic Rim Planning Scheme directly. Rural properties may have more generous allowances. |
| Somerset | Varies by precinct | Varies | Varies | Check Somerset Regional Council Planning Scheme directly. Predominantly rural area with variable provisions. |
Read this before using the table: These are simplified, indicative figures. Many councils have additional conditions based on lot size, frontage width, precinct-specific rules, overlay requirements and proximity to the primary dwelling. A number that appears in a table is not the same as an approval on your lot. Start here, then verify with your council.
Council-by-Council Breakdown
Brisbane City Council
Brisbane has one of the more generous size allowances in SEQ. Under the Brisbane City Plan 2014, a secondary dwelling can be up to 80m² GFA in most residential zones, and up to 100m² on rural-zoned land.
The key condition is proximity: the secondary dwelling must be within 20 metres of the primary dwelling to be assessed as part of a dwelling house. Beyond 20m, the assessment shifts — potentially into dual occupancy territory, which requires a development application and carries infrastructure charges.
If your dwelling meets the 80m² limit, stays within setbacks, and complies with height caps, it’s typically classified as accepted development. That means no formal planning application to council — just building approval through a private certifier.
Note: Brisbane is currently progressing Major Amendment Package L, which proposes refined design requirements for secondary dwellings including size limits relative to site size, a 50% total site cover cap, and height restrictions (one storey, or two storeys only where the primary dwelling is two storeys). Consultation closed December 2025 — check for updates.
Planning map: Brisbane City Plan Interactive Mapping
Full guide: Granny flats in Brisbane: rules, sizes and costs
City of Moreton Bay
Moreton Bay amended its planning scheme in October 2024, tightening suburban secondary dwelling rules while leaving rural and rural residential provisions largely unchanged.
In the General Residential zone, the GFA limit is now 45m² on lots up to 800m², and 55m² on lots over 800m². In the Rural Residential and Rural zones, the limit is up to 100m², which is the most generous in SEQ for those zones.
A key Moreton Bay requirement: in the General Residential zone, the secondary dwelling must be within 10 metres of the primary dwelling — significantly tighter than the 20m rule in most other councils. In rural and rural residential zones, the distance extends to 50 metres.
The council also requires shared services: one driveway, one letterbox, one street number, shared utility metering. This is specifically designed to maintain the “in conjunction with” relationship and prevent secondary dwellings from functioning as independent properties.
Why this matters for Outhaus: Our Haus 13.5 at 54m² internal area fits within the 55m² Moreton Bay GFA limit on lots over 800m². On smaller suburban lots, the 45m² limit requires careful model selection. On rural and rural residential land — including the Dayboro, Samsonvale, and Mount Mee areas where we’ve already built — the 100m² limit provides substantial flexibility.
Planning map: City of Moreton Bay ArcGIS Planning Map
Full guide: Granny flats in Moreton Bay: rules, sizes and costs
Gold Coast City Council
The Gold Coast allows up to 80m² GFA for secondary dwellings in residential zones, and up to 90m² in rural and rural residential zones.
The dwelling must be small in scale and clearly ancillary to the primary dwelling. One additional on-site car park is required beyond what the primary dwelling needs. Site cover is capped at 50%.
Gold Coast also applies a residential density overlay that affects what’s buildable on your specific lot. Some areas have tighter restrictions, and the hinterland rural zones have different provisions from the coastal urban zones.
Planning map: Gold Coast City Plan Interactive Mapping
Full guide: Granny flats on the Gold Coast: rules, sizes and costs
Logan City Council
Logan has a tiered system based on lot size. On lots under 1,000m², the maximum GFA is 70m². On lots of 1,000m² or larger, the limit increases to 100m² with a total use area (including carport and outdoor living) of up to 100m² excluding car parking.
The dwelling must be located within 20 metres of the primary dwelling and positioned behind it. Logan is particularly strict about the secondary dwelling being visually subordinate to the main house.
Minimum lot size is 450m² with a 15m frontage. Setbacks follow the Queensland Development Code.
Planning map: Logan Planning Scheme Interactive Map
Full guide: Granny flats in Logan: rules, sizes and costs
Sunshine Coast Regional Council
The Sunshine Coast allows 60m² GFA in most residential zones and 90m² in rural and rural residential zones.
A notable exception: in Caloundra South and certain coastal character precincts (Moffat Beach, Shelly Beach, Dicky Beach), the limit drops to 45m² with a 4-metre height cap. These tighter controls are designed to protect neighbourhood character in established beachside areas.
The dwelling must be within 20 metres of the primary house and on a lot of at least 600m² in urban zones. One additional on-site car park is required. Shared services — driveway, letterbox, metering — are mandatory.
The Sunshine Coast Planning Scheme requires a “similar external appearance” between primary and secondary dwellings in terms of materials and colours. This is a design control that doesn’t exist in all council areas.
Planning map: Sunshine Coast Planning Scheme Interactive Mapping
Full guide: Granny flats on the Sunshine Coast: rules, sizes and costs
Ipswich City Council
Ipswich used to be the most restrictive major SEQ council for secondary dwelling size. That changed on 1 July 2025, when the Ipswich City Plan 2025 commenced and replaced the Ipswich Planning Scheme 2006 that had run the city for nearly two decades.
Under the old scheme, granny flats were treated as “auxiliary units”, capped at 50m² with a maximum of one bedroom and required to sit behind the main house. Under City Plan 2025, self-contained secondary dwellings of up to around 80m² are supported, and council reports that roughly 22,000 properties can add one without a formal development application.
That moves Ipswich from the tightest cap in SEQ to among the more generous, and it puts the full Outhaus range in play rather than studio layouts only. Exact limits still vary by zone and lot, and the scheme is new enough that the detail is bedding in, so confirm the current provisions for your address before you commit to a design.
Planning map: Ipswich Planning Scheme Interactive Map
Full guide: Granny flats in Ipswich: rules, sizes and costs
Redland City Council
Redland is mid-transition. The council is currently progressing Major Amendment 02/25, which will introduce updated secondary dwelling provisions into the Redlands City Plan.
In the interim, the Amenity and Aesthetics Policy and Guideline (effective from February 2024) applies. This includes design requirements and infrastructure charging provisions for secondary dwellings that exceed certain thresholds.
The details are more complex than a single GFA number, and they’re actively changing. If you’re building in Redland, engage a town planner or certifier who’s current on the amendment status. The council withdrew earlier proposed amendments in October 2025 and folded them into the broader 02/25 package.
Planning map: Redland City Plan Interactive Mapping
Full guide: Granny flats in Redland: rules, sizes and costs
Noosa Shire Council
Noosa allows a maximum of 65m² internal floor area for secondary dwellings, with a maximum of two bedrooms. This applies across zones — the council doesn’t differentiate as significantly between rural and residential as some other councils do.
One additional car park is required. Infrastructure charges may apply. The Noosa Planning Scheme has strong environmental and character controls, so overlays are particularly relevant.
Planning map: Noosa Planning Scheme Interactive Mapping
Full guide: Granny flats in Noosa: rules, sizes and costs
Scenic Rim and Somerset Regional Councils
Both of these are predominantly rural council areas with smaller populations and fewer standardised secondary dwelling builds. Provisions exist but vary by precinct and zone within each planning scheme.
If you own rural land in either council area and want to explore secondary dwelling options, contact the council’s planning team directly or engage a local building certifier. The acreage allowances in these areas can be substantial — but they come with overlay considerations (bushfire, flooding, vegetation) that urban properties don’t typically face.
Scenic Rim: Scenic Rim Planning Scheme
Somerset: Somerset Regional Council Planning Scheme
What’s Changing — The Distinctly Queensland Design Series
The Queensland State Government is developing statewide siting and design provisions for secondary dwellings through the Distinctly Queensland Design Series. Consultation on a proposed State Code closed in November 2024.
The draft provisions proposed a maximum GFA of 80m² on lots under 1,000m², with provisions allowing good design outcomes including two-storey configurations. The intent is to create consistent, statewide rules that reduce the variation between councils and simplify the approval pathway.
If enacted, these provisions could override some of the council-specific limits listed above — particularly in parts of Moreton Bay (currently 45m² on suburban lots). However, the final form and timing of these reforms remain uncertain.
We’ll update this guide when the State Code is finalised.
What GFA Actually Means (And What It Excludes)
Gross floor area is measured to the outside of the external walls. In most councils, the following are excluded from GFA:
- Patios and covered outdoor living areas
- Decks (roofed or unroofed)
- Carports and garages
- Eaves and awnings
This matters because it means your liveable space extends beyond the GFA number. A 60m² secondary dwelling with a 15m² covered deck and a carport delivers significantly more usable area than the GFA alone suggests.
However, be careful: some councils measure “total use area” differently, and site cover calculations include roofed outdoor areas. The GFA limit gets you through planning — but site cover, setbacks and height limits all constrain the total footprint.
Infrastructure Charges — The Hidden Variable
Some councils levy infrastructure charges on secondary dwellings. Others don’t — or only charge above certain thresholds. This can add $15,000–$30,000+ to your project cost, and it’s the expense most people don’t see coming.
| Council | Infrastructure Charges for Secondary Dwellings |
|---|---|
| Brisbane | Generally no charges for secondary dwellings meeting accepted development criteria |
| Moreton Bay | Generally no charges for compliant secondary dwellings (charges apply for dual occupancy) |
| Gold Coast | Charges may apply — check with council based on your specific development |
| Logan | May apply — council determines based on development type and scale |
| Sunshine Coast | May apply — check Adopted Infrastructure Charges Resolution |
| Ipswich | Confirm under Ipswich City Plan 2025 (commenced 1 July 2025). The former no-charge position applied to auxiliary units under the 2006 scheme. |
| Redland | Charges apply above certain GFA thresholds per Amenity & Aesthetics Policy |
| Noosa | May apply — check with council |
Infrastructure charges are separate from your dwelling cost and your site preparation costs. Factor them into your budget from the start — not as an afterthought.
How to Use This Guide
Step 1: Find your council in the table above and note the GFA limit for your zone.
Step 2: Go to your council’s interactive planning map (linked in each section) and confirm your property’s zoning and any overlays that apply.
Step 3: Check proximity rules — most councils require the dwelling to be within 10–20 metres of your primary house. On acreage, this may extend to 50m.
Step 4: Ask about infrastructure charges before you budget. A phone call to council or your certifier can clarify this in five minutes.
Step 5: Engage a private building certifier to confirm the approval pathway for your specific lot. What looks compliant on a table may not be compliant on your site once overlays, setbacks, site cover and access are factored in.
If you want to understand the broader process — what a secondary dwelling actually is, how building classifications work, what approvals are needed — read our companion article: What Is a Secondary Dwelling? (And What Isn’t).
For acreage-specific guidance including bushfire, soil testing, transport logistics and crane access, see: Building a Secondary Dwelling on Acreage in SEQ.
Where Outhaus Fits
Our range is designed around the real-world size limits that exist across SEQ councils:
| Outhaus Model | Internal GFA | Fits Within |
|---|---|---|
| Studio 6.0 | ~19m² | All SEQ councils |
| Studio 8.0 | ~26m² | All SEQ councils |
| Haus 10.0 | ~32m² | All SEQ councils including Caloundra coastal (45m²) |
| Haus 13.5 | ~54m² | Brisbane, Gold Coast, Logan, Ipswich, Sunshine Coast (urban), Moreton Bay (lots >800m²), Noosa |
| Haus 15.0 (4.0m series) | ~60m² | Brisbane, Gold Coast, Logan, Sunshine Coast (at limit), Moreton Bay Rural/Rural Res |
| Haus 17.0 (4.0m series) | ~68m² | Brisbane, Gold Coast, Logan (lots >1,000m²), Moreton Bay Rural/Rural Res |
Every model is built to Class 1a residential standards — the same construction classification as your primary house. We don’t build to the limits of what’s cheap. We build to the limits of what’s allowed, at the quality level of what’s proper.
If you want to discuss which model fits your council area, your lot and your situation, we start with a conversation — not a quote. And if you want to see them in person, visit Outhaus Ranch at 472 Laceys Creek Road, Laceys Creek QLD.
This guide is general information only and is not legal, planning or building advice. Council planning schemes change regularly — some of the figures above may have been amended since this guide was last updated. Always confirm current requirements with your local council and a qualified building certifier before committing to a build. Last updated: February 2026.