What does a granny flat site plan need to show?

The new dwelling on the real lot, with its size, its distance to every boundary and to the main house, and the share of the lot under roof once it is built. A granny flat (a secondary dwelling, officially) is assessed against those numbers first, and the site plan is the drawing that shows them, before anyone commits to a slab.

To check a particular block, type its address into RapidSiteplan: it reads the lot and the rules that apply there and checks the granny flat you place against them, in minutes.

What must the site plan show?

The existing house and every other structure on the lot
The proposed granny flat, dimensioned, with setbacks to every boundary and to the main dwelling
Site coverage and the separation distance council checks
Access, the driveway, and where the services connect

What usually sinks a granny flat application?

Sitting it too close to a boundary, and pushing the total site coverage over the limit. Both are invisible on a hand sketch. Both are obvious the moment you draw the dwelling to scale on the real lot, and that is exactly when you want the bad news: while it is still a drag-and-drop fix, not a letter from the certifier.

Does a granny flat need council approval?

Yes, in some form. A granny flat is a dwelling, so it needs building approval in every state, and often planning approval as well. In some states one that meets the state's standards can go through a quicker code-based approval from a certifier; elsewhere, or where an overlay applies, the council decides a planning application first. Your certifier or council can tell you which path your lot is on.

What only your address can answer

the setbacks and site cover the rules set for a lot of your size and zone
whether the lot is big enough, or wide enough, for a second dwelling
which overlays your council has mapped over the block
easements and sewer mains where the granny flat would go
how the services and the driveway reach it

RapidSiteplan reads your own block from its address: the boundaries, the buildings already on it, the rules that apply there and any overlay or easement, and checks what you plan to build against them on a scaled site plan.

The post on getting your house plans from council covers the records of the existing house.

Search your address to start. Site plans and assessments in minutes.

Sources: the siting rules a site plan is read against, by state, all read in September 2026: Queensland Housing Code (Qld); State Environmental Planning Policy (Exempt and Complying Development Codes) 2008 (NSW); Building Regulations 2018 (Vic); Planning and Design Code (SA); Residential Design Codes Volume 1 (WA); Tasmanian Planning Scheme, State Planning Provisions (Tas); Planning (Exempt Development) Regulation 2023 (ACT); NT Planning Scheme 2020 (NT).

Common questions

Do I need a site plan for a granny flat? Yes. A secondary dwelling application in every state needs a site plan showing the new dwelling on the lot, its distances to every boundary and to the main house, and the site coverage.

How close to the boundary can a granny flat be? It depends on your state, your council and the lot. The siting rules set a minimum distance to each side and rear boundary, and the figures have to be shown on your site plan. Check with your council or certifier for the figure that applies to your lot.

Can I draw the granny flat site plan myself? Usually, yes. Councils and certifiers generally accept a clear, to-scale site plan from anyone, as long as the boundaries, dimensions and setbacks are right. The design and engineering of the granny flat itself come from qualified people, and your certifier may ask for a survey if it sits close to a boundary.