Queensland: Brisbane City Council on filling and excavation, and the Building Regulation 2021 (Qld).
New South Wales: the Planning Portal on exempt development for earthworks and on complying development.
Victoria: the Building and Plumbing Commission on protecting adjoining properties.
When a block needs an approval
In Brisbane and New South Wales, the rules hinge on a measurement: how deep the cut goes or how high the fill rises. Brisbane divides its two decisions at one vertical metre.
New South Wales counts in millimetres for its complying development route, and lists conditions for its exempt route instead of a single number.
Victoria's page states no depth line. Its trigger is the building permit application, and the surveyor's decision on whether protection work is required.
Queensland's regulation also declares some filling or excavation accepted development, its self-assessable route, opening with the words “building work that is filling or excavation for a building or structure”, then setting four conditions that work together:
- the proposed cut or fill is no deeper than 1m above or below the natural ground surface, and
- any cut embankment is only into a listed soil type and no steeper than that type's gradient: sand 2 horizontal to 1 vertical, silt 4 to 1, firm clay 1 to 1, soft clay 3 horizontal to 2 vertical, and
- any fill embankment is no steeper than 4.0 horizontal to 1.0 vertical, and
- any compacted fill embankment is only into the listed soil types and no steeper than the gradient stated for it: sand 3 horizontal to 2 vertical, silt 4 to 1, firm clay 2 to 1.
Queensland
The council's planning line: a project that raises or lowers the ground by up to one vertical metre needs no planning approval, unless a neighbourhood plan or an overlay says otherwise.
Where planning approval is needed, the path runs through a development application, and the council notes that a fee quote follows and that its points system sets the amount.
The application has its own clock. An application that is not properly made draws an action notice with 20 days to comply, and the council issues a confirmation notice once it is satisfied.
The building line is separate: filling or excavating more than one vertical metre for the purpose of constructing a building or structure needs building approval, organised through a licensed building certifier.
The Building Regulation 2021 (Qld) commenced on 1 September 2021, and the list above sets out its accepted development route.
New South Wales
In New South Wales, earthworks, retaining walls and structural supports may not need planning approval at all: the Planning Portal classes them as exempt development when the State policy's conditions are met.
For earthworks, retaining wall and structural support developments to be exempt from planning consent, State policy requires them to:
- not be carried out, constructed or installed on or in a heritage item or a draft heritage item;
- be constructed or installed in the rear yard, if in a heritage conservation area and draft heritage conservation area;
- be located at least 40 metres from a body of natural water;
- not redirect the flow of any surface water or ground water, or cause sediment to be transported onto an adjoining property;
- be separated from any other retaining wall on the site horizontally by at least 2 metres.
Past the exempt route comes complying development: earthworks and structural supports exceeding 600 millimetres above or below ground level may be done that way.
The same Planning Portal page adds that the works must be structurally adequate and comply with the Building Code of Australia.
Any structure on public land or a road needs approval from the council or Transport for NSW.
The page also says that, generally, exempt development cannot be carried out on certain land, including land or a building listed on the State Heritage Register or subject to an interim heritage order, and a wilderness area under the Wilderness Act 1987. The State policy itself also rules it out on land declared an area of outstanding biodiversity value under the Biodiversity Conservation Act 2016, or declared critical habitat under Part 7A of the Fisheries Management Act 1994.
Tree removal or pruning sits beside the earthworks: the portal's advice is to check with the council before touching existing trees or vegetation.
Victoria
The Victorian route starts with the building permit application: the applicant gives the relevant building surveyor detailed information about the work, and the surveyor then decides whether protection work is required.
Where protection work is required, a notice is served on the adjoining owner with the details, and no building permit can be issued before that process is complete to the surveyor's approval.
If the adjoining owner disagrees or asks for more information, the surveyor examines the proposal and determines whether the protection work is appropriate.
The determination is given in writing to both owners, and either may appeal it within 14 days to the Building Appeals Board.
Once the adjoining owner agrees to it, or is deemed to have agreed, and the surveyor has evaluated the work, the builder may start the protection work once any necessary permits, approvals or insurance are in place.
Money runs with the process: the law puts the adjoining owner's costs of protecting their interests on the property owner.
The three answers, side by side
| State | What its rule asks for |
|---|---|
| Queensland | In Brisbane, no planning approval up to one vertical metre unless the site is in a neighbourhood plan area or affected by an overlay, and building approval past one vertical metre for construction. Across Queensland, the Building Regulation 2021 has a self-assessable route with four conditions that must all be met. |
| New South Wales | Exempt development when the State policy conditions are met (generally not on State Heritage Register or wilderness land, and not on a declared area of outstanding biodiversity value or declared critical habitat), or complying development for earthworks exceeding 600 millimetres above or below ground level. |
| Victoria | A permit that waits on the protection work process: the surveyor decides whether protection work is required, the adjoining owner is served, and a permit may not be issued until the process is complete. |
What an approval is not
Planning approval and building approval are two different decisions with two different processes, and a project can need one, the other, or both.
An exemption from planning consent is not an exemption from the building rules: New South Wales still requires structural adequacy and compliance with the Building Code of Australia on its exempt route.
None of these approvals covers what is underground. The enquiry with Before You Dig Australia is a separate step with its own lead time, and a plan from it is not an approval to dig.
The state pages carry their own pointers to further steps: a council or Transport for NSW approval for structures on public land, and a check with the council before removing trees.