The data · 2026 edition
The Granny Flat
Cost Report. 2026.
What granny flats cost in Queensland, from invoiced builds rather than advertising. Published so buyers can check any quote, including ours.
A finished one-bedroom granny flat in SEQ costs $210,200 to $223,200 fully installed in 2026, or roughly 16% less owner-built. Approvals run $16,700 to $19,750 invoiced, site works $20,000 to $51,000 depending on access.
Why this report exists
Every granny flat ad in Australia shows part of a price. Nobody publishes what the whole project costs, because almost nobody who sells the boxes also finishes the homes, coordinates the approvals and pays the invoices. We do, so we published ours. The figures below come from invoiced completed builds, our published August 2026 price list, and a freight model anchored to quoted carrier rates. It updates annually.
Finding 1: the whole number, by route
A one-bedroom granny flat (Standard 8.4, 28.6sqm) finished and liveable in South East Queensland, by how much of the work the owner takes on:
| Route | You pay the maker | Finished and liveable, typical |
|---|---|---|
| Kit, owner-built | $59,900 | $158,800–$207,600 |
| Lock-up, owner-finished | $75,900 | $174,800–$212,700 |
| Complete + installer | $139,900 | $176,900–$189,900 |
| Fully installed | – | $210,200–$223,200 |
The headline: the do-it-yourself discount on a finished granny flat is roughly 16%, around $35,000 on a $215,000 project, and it costs the owner 300 to 400 hours of labour and the project risk. The gap between routes is far smaller than kit advertising implies, because the fit-out, site and approvals exist on every route.
Finding 2: what approvals cost, invoiced
Invoiced consultant and certification costs on a completed Brisbane build (full development application pathway, 2026):
| Item | Invoiced |
|---|---|
| Certification, DA, referrals and final | $8,617 |
| Survey, set-out and Form 12 | $2,200 |
| Soil test and report | $770 |
| Underground service location + CCTV | $2,200 |
| Energy report | $534 |
| Structural design and inspections | $2,400 |
| Total, all approvals consultants | $16,721 |
A comparable accepted-development job in Moreton Bay quoted $16,400 to $17,600 on the same structure. Working band across our jobs: $16,700 to $19,750 inc GST. Site works ran $20,000 to $33,000 on straightforward access and $30,000 to $51,000 where a 27m main-road crane lift and traffic control were needed.
Finding 3: freight, indexed
Flat-packed kits travel on standard trucks with no pilots. Finished modules travel as wide loads. Approximate landed freight for a one-bedroom kit and module from our SEQ yard, by destination band:
| Destination band | Kit freight | Module freight |
|---|---|---|
| SEQ (to 200km) | ~$600 | ~$1,000 |
| Regional QLD (to 700km) | ~$850–$1,950 | ~$2,500–$3,300 |
| Long haul QLD (to 1,600km) | ~$2,600–$4,400 | ~$4,400–$7,450 |
| Far QLD and interstate | ~$3,100–$14,650 | ~$5,250–$24,750 |
| Tasmania (Bass Strait leg included) | ~$10,800 | ~$17,400 |
Two structural cost effects worth knowing: cyclonic wind regions (coastal Queensland from Bundaberg north, coastal NT) add roughly $7,500 of engineering to any product, and Moreton Bay’s October 2024 planning amendment capped suburban granny flats at 45sqm, the tightest in South East Queensland.
Straight answers
Where does this data come from?
Invoiced completed Outhaus builds in Brisbane and Moreton Bay, the published Outhaus price list of August 2026, and carrier rates on file. Estimates are labelled as estimates.
Can I use these figures?
Yes, with attribution to the Outhaus Granny Flat Cost Report 2026. The report exists so buyers, journalists and researchers have real numbers in a market that advertises half-projects.
Do these prices apply outside Queensland?
Kit and module prices are national, ex our SEQ yard; the freight index covers every state. Approvals and site works vary by state and council, and the invoiced figures here are Queensland jobs.
Where this lands on price
Every price, every way to buy, on one page.
Kit $59,900 to finished and installed, with the all-in number printed.