Two approvals, asked for in two places
The planning department says any new secondary dwelling needs building approval, and that you still need to speak with your council to learn whether it needs development approval before building. The same goes for converting an existing structure into a granny flat, and councils have some different rules on building approvals.
Plumbing and drainage approvals also go through the local council. The commission says it is the homeowner’s responsibility to have the right building approvals in place before work starts, even when a builder has been hired.
What the certifier does, and does not do
A building certifier can work for a council or in private practice. Usually the builder engages one for you, though you can appoint one directly, and your contract should say who does it. A private certifier must give the owner a notice with their contact details and responsibilities (Form 18) within 15 days of being engaged.
| The certifier does | The certifier does not |
|---|---|
| Assess and approve the plans | Design the building or do any of the work |
| Inspect the work at mandatory stages, such as before concrete is poured for the footings or slab, and after the frame is up but before the internal walls go on | Supervise the site, or check that the builder keeps to the contract |
| Give certificates of inspection to the owner, the contractor and the local authority, and issue enforcement notices where needed | Answer for quality and finishes, such as paintwork |
| Give final approval for the building to be occupied | Pay the assessment and inspection fees of referral agencies, such as a council |
The paperwork at the end
For a detached house or a smaller structure, the certifier issues a final inspection certificate (Form 21), which shows the work is finished and complies with the building approval. It typically goes to the owner and is lodged with the council. A certificate of occupancy (Form 11) is the version for multi-storey apartments and townhouses.
Wet areas need a waterproofing certificate when the waterproofing work is worth more than $3,300 (as at October 2026). A practical completion certificate under a building contract is not a regulatory requirement and says nothing about whether the building is fit to live in.
If inspection certificates for earlier stages are missing, an owner can ask the certifier for them on Form 35, and the certifier has five business days to provide them.
The tiny home in the back corner
The commission uses “tiny home” broadly: prefabricated pods, flatpack or kit studios, transportable and relocatable homes, modular homes, backyard studios, and granny flats or secondary dwellings, usually made off site and delivered, assembled or installed on a residential property.
On wheels, or on the ground?
A tiny home on a trailer that is not fixed to the land or connected to utilities is treated as a caravan, under vehicle registration rules rather than building laws. Once it is fixed to the land and used as a home, it becomes a Class 1a building and has to meet every building, planning and plumbing requirement.
Who may install one
Installing a tiny home is residential construction work when it is fixed to the ground, by footings, tie-downs or service connections for example, and intended for use as a Class 1a home. Then a contractor with a QBCC licence must install it, unless the owner holds an owner-builder permit.
What the commission suggests before buying
- Check planning and zoning with the council.
- Engage a private building certifier to work out the approvals needed and the path to Class 1a compliance.
- Plan it like any home build: site access, services and engineering.
- Ask the supplier for engineering, tie-down details and product information.
- Keep copies of approvals, certificates, contracts and warranties.
Going ahead without approvals can lead to enforcement action and penalties, including from the council.
What the home warranty scheme covers
The Queensland Home Warranty Scheme can apply to the on-site work of installing a tiny home, such as footings, service connections and assembly. It does not cover making the home off site, transporting it, or faults in the product itself, for which the commission points to the Australian Consumer Law, the Office of Fair Trading and any manufacturer’s warranty. It does not apply where the owner assembles the home as an owner-builder.
If it will be rented
Since 26 September 2022 a Queensland secondary dwelling can be rented to anyone. The planning department warns that a change to how an existing granny flat is used can trigger a building application: once it is rented out, additional fire and sound transmission requirements of the building code apply, and it suggests advice from a building certifier. The Residential Tenancies Authority’s secondary dwellings page covers the tenancy side, and the renting stop on this lot covers meters and smoke alarms.
The other stops
Five more places on the same lot: