Granny Flat Logan: 70m² or 100m²? 2026 Council Rules Explained
Last updated: 16 September 2026
Most Logan homeowners do not need a planning application to build a granny flat. Under the Logan Planning Scheme, a secondary dwelling up to 70m² on a lot under 1,000m², or 100m² on a larger lot, is accepted development. You will still need building approval from a private certifier, and infrastructure charges apply.
Logan runs three separate development categories for what most people call a granny flat, and choosing the right one determines your size limit, your costs and whether you can rent it out. Getting that choice wrong is the most expensive mistake in Logan.
Quick answer
Council planning approval needed? Usually no. Secondary dwellings are accepted development.
Maximum size 70m² on lots under 1,000m². 100m² on lots of 1,000m² or more.
Distance from the main house Within 20 metres. Beside, behind, above or below. Not in front.
Building approval needed? Yes, always, via a private certifier.
Infrastructure charges? Yes. They apply to secondary dwellings as well as auxiliary units.
Separate water meter? Yes, required. Sewer connection may be shared.
Bins A bin service is required for each dwelling, with charges.
The three categories, and why it matters
Logan is unusual. Most councils have one pathway. Logan has three, and they carry different size limits, different costs and different occupancy positions.
Secondary dwelling. A self-contained dwelling on the same lot, same title, same owner as the main house. This is the standard granny flat pathway and it is accepted development.
Auxiliary unit. Formally a type of dual occupancy. Same owner, one title, minimum lot size 450m². Subject to its own siting, frontage and parking requirements, and specifically contemplated for a separate household. Generally accepted development in the low density residential zone.
Dual occupancy. Two dwellings of comparable standing. Can be separately owned and titled. No size or bedroom cap, but a more involved approval process.
Work out which one applies before you design anything. The quickest way is the Logan PD Hub: find your property, select "What can I do here", and the report lists your zone, your overlays, whether each option is accepted or assessable, and the codes you need to address.
Secondary dwellings
Size
Lots under 1,000m² — maximum 70m² gross floor area
Lots 1,000m² or more — maximum 100m²
Gross floor area is measured around the outside of the walls and excludes patios, decks and carports. On larger lots the total use area including carport and outdoor living can run to around 100m² excluding car parking.
Siting
The secondary dwelling must sit within 20 metres of the primary dwelling and be positioned beside, behind, above or below it. Attached or detached are both fine.
Placing it in front of the main house typically pushes you into assessable development. Logan is particularly strict about the secondary dwelling reading as visually subordinate — the site should still present to the street as one home, with one address and the driveway primarily serving the main house.
Setbacks and height
Treat the granny flat under Dwelling House controls. Height, setbacks and building envelopes follow the planning scheme and the Queensland Development Code as applied in Logan. Missing an acceptable outcome generally moves you into assessable development.
Parking
Where the secondary dwelling is attached, a minimum of two on-site car spaces in total. Auxiliary units carry different standards — see below.
Services
Separate water meters are required for secondary and auxiliary developments
Both may share a single sewer connection point
A bin service is required for each dwelling, and charges apply
Infrastructure charges
Infrastructure charges apply to secondary dwellings in Logan. This is often misreported, including by sources suggesting charges only attach to auxiliary units or dual occupancies. They do not.
Estimate yours using the Infrastructure Charges Estimator in the PD Hub, and build it into your budget from the start rather than discovering it late.
Other requirements
Same lot, same owner, one title. Cannot be subdivided or separately titled.
Auxiliary units
An auxiliary unit is formally a category of dual occupancy, and it is generally accepted development in the low density residential zone, subject to the code.
Size and layout
Lots under 1,000m² — maximum 70m²
Lots 1,000m² or more — maximum 100m²
Maximum two bedrooms, one kitchen, one living space
Minimum lot size 450m²
Frontage
A minimum 15 metre frontage on a standard, non-rear lot.
Parking and driveways
Five on-site car spaces in total, two of which must be covered, shared with the main house.
The unit shares a driveway with the main house, unless the lot is a corner lot or has dual road frontage.
Siting
Beside, behind, above or below the main house, within 20 metres. Fire separation may be required under the National Construction Code — your building certifier will advise.
Charges
Infrastructure charges apply.
Can you rent out a granny flat in Logan?
This is where Logan differs from Brisbane and the Gold Coast, and where most published information is out of date in one direction or another.
The statewide position changed in 2022. On 26 September 2022, an amendment to the Planning Regulation 2017 removed the requirement that a secondary dwelling be occupied by a member of the primary household. That change applies across Queensland and remains in place as at September 2026. The Queensland Government maintains current guidance on secondary dwellings.
Logan's scheme still runs two distinct pathways. The auxiliary unit category exists specifically to accommodate a separate household, carries its own frontage, parking and siting benchmarks, and is the pathway Logan has historically directed rental proposals toward.
What to do in practice: run your address through the PD Hub and confirm which category your proposal falls under before you design or commit. If you intend to tenant the dwelling, raise it explicitly at that point. The difference between the two pathways changes your parking requirement from two spaces to five, which materially affects what fits on your block.
Whichever category applies, three things hold:
It stays on the same title and cannot be sold separately.
Tenanting can trigger additional fire separation and sound transmission requirements under the building code. Raise it with your certifier.
If an existing approval carries occupancy conditions, you may need a change application under the Planning Act 2016.
Overlays
Logan has extensive overlays that can add benchmarks or flip you into assessable development even when your size and siting comply:
Flooding and overland flow
Bushfire hazard
Biodiversity areas
Landslide and steep land
Waterway corridors and wetlands
Transport corridors
Check them at the start through the PD Hub, not after you have a design you like.
What if my plans don't meet these requirements?
You can usually still build, via a development application. Common triggers:
Exceeding your lot's gross floor area limit
Siting more than 20 metres from the main house, or in front of it
Frontage, parking or setback non-compliance
An overlay affecting the property
If you want two genuinely independent, separately titled dwellings, dual occupancy is the pathway. It carries no size or bedroom cap but a more involved process, and in some zones it is accepted development while in others it needs a full application.
Which designs work in Logan
The 70m² and 100m² split makes lot size the deciding factor here more than in any neighbouring council.
Lots under 1,000m² — the 70m² band. The Olive 60 two-bedroom granny flat, Valencia 60,and Amber 60 all sit inside it, with decks that don't count toward gross floor area.
Lots 1,000m² and over — the 100m² band. This is where Logan gets generous. The Amber 80 three-bedroom secondary dwelling, Onyx 80, Olive 80 and Jasper 80 all fit comfortably, with room to spare.
Tight or constrained sites. The Seville 40 and Seville 50 suit blocks where site cover or the 20 metre siting rule limits the footprint.
See the full range, or look through completed projects.
Frequently asked questions
How big can a granny flat be in Logan? 70m² gross floor area on lots under 1,000m², or 100m² on lots of 1,000m² or more. Decks, patios and carports are excluded.
Do I need council approval for a granny flat in Logan? Usually no planning application, if you meet the accepted development criteria with no triggering overlays. Building approval from a private certifier is always required.
Do infrastructure charges apply to a granny flat in Logan? Yes. Infrastructure charges apply to secondary dwellings as well as auxiliary units. Estimate yours in the PD Hub.
How far from the main house can it be? Within 20 metres, positioned beside, behind, above or below. Placing it in front of the main house typically triggers assessment.
What is the difference between a secondary dwelling and an auxiliary unit in Logan? A secondary dwelling is the standard granny flat pathway on the same title with the same owner. An auxiliary unit is a form of dual occupancy with its own frontage, parking and siting requirements, contemplated for a separate household. They carry the same size limits but different benchmarks.
Do I need a separate water meter? Yes. Separate water meters are required. The sewer connection may be shared.
Can a granny flat be sold separately in Logan? Not as a secondary dwelling or auxiliary unit. Only a dual occupancy can be separately titled.
How many car spaces do I need? Two on-site spaces in total for an attached secondary dwelling. Five in total for an auxiliary unit, two of them covered.
How Compact Homes can help
Logan's three categories catch people out more than any other council in South East Queensland, and the wrong choice changes your parking requirement, your charges and whether you can tenant the dwelling. We work that out first.
Our approval package is $12,500 and covers architectural drawings, soil testing, engineering, surveying, certifier fees, energy efficiency compliance, and full management through to a building approval for your block.
Guides for other Southeast Queensland councils
We know the development requirements around secondary dwellings well, but we are not town planners. If you need formal planning advice, let us know and we can point you to someone. Planning rules change — always confirm the current position with Logan City Council before relying on this guide.