Australia’s independent granny flat research hub

Your Independent Guide to Granny Flats & Tiny Homes

Honest cost breakdowns, pro and con supplier reviews and council approval advice. No sales pitch, just the research you need before you build.

100% independent Updated September 2026 No sales pressure

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We cover Prefab & modular DIY kits Custom builds Council approval Real costs

Small white backyard cottage granny flat — Photo by Pixabay on Pexels

Residential construction site for a new small dwelling — Photo by Pixabay on Pexels

Backyard studio cabin on a residential block - Australian secondary dwelling backyard build — Photo by RDNE Stock project on Pexels

Builder inspecting timber frame of a new backyard dwelling — Photo by Anamul Rezwan on Pexels

Start here

What’s Your Project Goal?

Pick the path that matches how you want to build. Each one links to a vetted directory and the research behind it.

Prefab & Modular Homes

Factory-built and craned to site for speed and cost certainty. Compare Australia’s leading providers.

Browse prefab providers

DIY Kits

The owner-builder route. Save the builder’s margin by assembling a supplied steel or timber kit yourself.

Compare kit suppliers

Custom Home Builders

A licensed local builder manages a fully bespoke design. Find vetted builders in your state.

Find custom builders

Guides & Costs

Still weighing it up? Start with our cost breakdowns, council approval guides and design ideas.

Read the guides

Compact backyard studio granny flat with modern exterior cladding

Why we exist

We're a research hub. We don't sell flats.

Most granny flat websites are run by builders trying to sell you their product. We don't sell kits and we don't employ salespeople. The Granny Flat Guide is here so you can see costs, rules and supplier trade-offs before you sign.

We publish the bits quotes often skip: the gap between prefab and custom, the fees inside council approval, and the downsides of each path as well as the pitch.

Real cost bands. Current 2026 pricing across kit, prefab and custom builds, including the site costs most quotes leave out.
Balanced reviews. Every supplier write-up covers the strengths and the weaknesses, so you see the full picture.
State-specific rules. Plain-English guides to council approval, setbacks and the 60 sqm threshold that trips up so many projects.

What you'll find here

Pick a starting point that matches where you actually are. Each path below is a page, not a sales funnel.

For people still deciding

Cost guides, the prefab versus kit versus custom comparison, and design ideas to help you shape a realistic brief.

Free cost calculator covering all four budget phases
Council approval explained state by state
Curated supplier directories, listed for free

Planning tools

Check Rules and Setbacks Before You Design

Free interactive tools for approval pathways, size limits, build-type trade-offs and separate metering ballparks. Indicative only; confirm with council and licensed trades.

Rules by state

Granny Flat Regulations in Your State

Size caps, approval pathways and rental rules differ nationwide. Start with the comparison hub, then open your state guide.

All states comparison

Sortable table with official .gov.au links for every state and territory.

Open rules hub

NSW

60 m² CDC pathway vs full DA when your lot does not comply.

NSW rules

Victoria

Part 5 small second dwelling exemptions and permit triggers.

VIC rules

Queensland

Statewide secondary dwelling rules beyond Brisbane metro.

QLD rules

Western Australia

R-Codes ancillary dwellings and Perth planning notes.

WA rules

South Australia

Code assessment and council variation triggers.

SA rules

Don’t build blind

Get the Budget Right Before You Commit

Material costs and council fees shifted again in 2026. Our free feasibility calculator helps you avoid the surprises that derail backyard builds.

Estimate Site Costs

Excavation, the slab, crane access and sewer connection are the variables that quietly blow budgets. Plan for them up front.

Compare Kit vs Custom

See where a DIY kit really saves money once you account for trades and your own time, versus a managed custom build.

See Where the Money Goes

Break your budget into preliminaries, site costs, the build and finishes so you know what builders leave out of the headline price.

Open the free cost calculator

Already have a ballpark? Compare free quotes from vetted suppliers.

Why trust us

An Independent Voice in a Crowded Market

We exist to help you decide, not to sell you a product. Here is how our research stays honest.

Rules and costs, not a pitch

We track current council pathways (CDC, Part 5, R-Codes) and typical 2026 quote bands. We don't take a commission on the jobs you book.

Pro and con reviews

Every supplier write-up covers the strengths and the weaknesses, so you see the full picture.

Checked against official pages

Regulation summaries link out to state planning portals and the ABCB. If a rule changes, the official page wins.

Good to know

Granny Flat Questions, Answered

The questions Australian homeowners ask us most, before they spend a dollar.

How much does a granny flat cost in Australia in 2026?

Finished 60 sqm projects we see quoted in 2026 usually sit somewhere around $120,000 to $250,000 turnkey, depending on site and finish. Per-square-metre bands of about $1,800 to $3,500 are a planning range, not a quote. A kit sticker near $30,000 is materials. Slab, trades and council fees typically close most of that gap. Plug your size into the calculator, then confirm with local quotes.

Do I need council approval to build a granny flat?

In NSW, a secondary dwelling under 60 sqm on a lot of at least 450 sqm can often go through Complying Development. That is the Housing SEPP pathway on the NSW Planning Portal, not a skip-council trick. Victoria, Queensland and WA each use different labels. Do not pay a deposit until you have checked your lot against the current state planning page.

Is it cheaper to build with a DIY kit?

A kit removes the builder margin, which can look like 20 to 30% on paper. You then take on project management, council, the slab, plumbing, electrical and fit-out. It works if you have time and a decent trade network. It bites if you are time-poor.

Prefab, kit or custom: which path should I choose?

Prefab and modular are usually the fastest and give you more price certainty, with less design freedom. A DIY kit is the lowest sticker price and the most work. A custom builder manages the risk on odd blocks, at a higher cost and a longer timeline. The supplier hub compares all three side by side.

Primary sources

Size caps, approval pathways and dollar bands on this page are planning ranges. Check the current official page before you lodge or sign.

See our editorial standards for how we research and update guides.

GFPublished by The Granny Flat Guide, independent Australian researchers. We are not a builder and we do not sell kits. Guides last reviewed September 2026. Editorial standards

Want names you can actually call?

Tell us the state, size and path you're considering. We'll check which vetted kit, prefab and custom suppliers currently have capacity. No sales script from us.

Check supplier availability

Prefer to research first? Read our in-depth guides or compare the three build paths.