The number of Queensland homeowners adding a granny flat to their property has grown steadily, and the reasons are practical: rental income, ageing parents, adult children who need somewhere to live. What has not grown at the same pace is awareness of the rules. The most expensive mistake in this process is getting plans drawn before knowing what the block actually allows.

This article covers what Queensland calls these structures, what the size and setback rules look like across the Gold Coast and Brisbane, when you need council approval, and what the process looks like from the point of calling us to having approved plans in hand.

Secondary Dwelling or Auxiliary Unit: What Is the Difference?

Queensland planning law uses two classifications for what most people call a granny flat, and the classification determines what rules apply.

A secondary dwelling is a self-contained residence on the same lot as the main house. It has its own kitchen, bathroom, laundry, and living areas. It is designed for independent living, which means it can be rented out on the open market.

An auxiliary unit is a smaller dwelling that is functionally attached or connected to the main house. It is designed for a household member, typically a family member, rather than independent tenants. The occupation conditions for auxiliary units are more restricted than for secondary dwellings.

The distinction matters because they sit in different parts of the planning scheme. Before we draw anything, we confirm which category applies to your situation, because the drawings need to reflect the correct classification.

Size and Setback Rules: Gold Coast and Brisbane

The rules on size and setbacks for granny flats in Queensland vary between council areas and depend on the zoning and lot size of the property.

Both Gold Coast and Brisbane councils link the allowable size of a secondary dwelling to the size of the lot. Larger blocks generally allow larger secondary dwellings. If the lot is small, the size of the granny flat may be constrained beyond any statewide maximum.

Setback requirements apply from the front boundary, side boundaries, and rear boundary, and in some configurations, from the main dwelling as well. Heritage overlays, flood overlays, and vegetation overlays can all affect what is permissible in a given location. Checking the applicable overlays for the specific property address is part of our standard process before we quote.

On the Gold Coast, the coastal management overlay affects properties in certain beachside zones and adds requirements beyond the base planning scheme. In Brisbane, bushfire and flood overlays affect significant portions of the outer suburbs and need to be checked early in any planning process.

When You Need Council Approval

A granny flat almost always requires a development approval before construction begins. In the vast majority of cases, this means a Development Application must be lodged and approved before the project can move to Building Approval. That is not a shortcut you can skip: the Development Application is where the council assesses whether the proposed structure is appropriate for your specific lot. Getting this step right from the start is what keeps the project on track.

It is worth knowing this upfront because it affects your timeline. A Development Application takes longer than a code-assessable pathway, and in Queensland, granny flat projects almost never qualify for the faster route. We will confirm which pathway applies to your property in the initial scoping conversation, and a townplanner may be engaged where the application requires planning expertise beyond the drawings themselves.

What We Produce and What the Process Looks Like

When you contact us about a granny flat, the first conversation covers the address of the property, the type of structure you are planning, and what records you have about the main dwelling. From there, we check the applicable planning scheme, confirm the classification and size constraints, and tell you what drawings the council will need.

We produce a full set of plans to the standard required by your council. For most Gold Coast and Brisbane granny flat approvals, that typically includes a site plan showing the location of both dwellings and all relevant setbacks, floor plans and elevations of the proposed structure, and the relevant details required by the applicable code.

Beyond concept and approval drawings, we also produce construction drawings. These are what your builder needs to price and tender the job, and having them ready means you can move directly from approval to builder engagement without a gap in the process.

We have done this across both council areas since 2016. We know what each council’s planning teams look for and we know which applications come back with requests for more information. Our job is to make sure yours does not.

A Few Questions on Granny Flats in Queensland

Can I rent out a granny flat in Queensland?
A secondary dwelling can generally be rented out on the open market, subject to the applicable planning scheme and any conditions attached to the approval. An auxiliary unit typically has more restricted occupation conditions. The classification of your structure determines the answer, and that classification is confirmed at the planning stage before any plans are drawn.

What does a granny flat approval cost?
The cost of the drawings is separate from the council application fees. We will give you a clear quote on the drawing scope when you contact us. The scope depends on the size and complexity of the proposed structure and which council area the property is in. Council application fees vary by council and by the type of application.

What size granny flat is allowed on my block?
The answer depends on your lot size, your zone, and the specific planning scheme that applies to your council area. Both Gold Coast and Brisbane councils link allowable size to the lot, and overlay conditions on the property can narrow that further. Contact us with the address and we will confirm what applies to your block in the first conversation.

We handle granny flat plans across the Gold Coast and Brisbane. Find out if your block qualifies.