The Height Limit That Does Not Come From Your Zone
The Height Limit That Does Not Come From Your Zone
General information for South Australian landowners only. This is not planning, aviation or engineering advice. Whether protected airspace affects your site, what surfaces apply, what referrals are required and what your proposal or its construction method does are questions for the relevant authorities, the airport operator, the Commonwealth agencies involved and your experienced planning consultant against your actual proposal. The governing legislation, regulations and published surfaces are amended over time, so confirm the live position before you rely on anything here.
Owners look up the wrong ceiling
The first thing an owner checks about a site is what the zone allows. It is the right first question, and on some sites it is not the operative one.
There can be a second ceiling over your land that has nothing to do with your zone, your council, or the Planning and Design Code — one set by a Commonwealth framework protecting the airspace around an airport, administered by parties who do not sit in your council building, and measured in a way that means two identical proposals on identical zoned sites do not have the same real limit.
It is not exotic. It is a plane of airspace that extends well beyond an airport's fence, and the sites under it look entirely ordinary from the ground.
This article is about where that constraint comes from and what it does to a project. It is not a statement that it applies to your site — whether it does, and what it permits, is for the relevant authorities and the airport operator against your actual proposal.
Where the limit comes from
The published framework is Commonwealth. The department states that it protects the airspace around leased federal airports under Part 12 of the Airports Act 1996 and the Airports (Protection of Airspace) Regulations 2026, which together establish the framework for protecting airspace at and around those airports (source: Department of Infrastructure — Protection of airspace).
Check which regulations any guidance is written against. The 2026 Regulations replaced the 1996 Regulations, so material published earlier may describe superseded arrangements — including material published by an airport. Confirm the current position with the department rather than assuming a document is current.
Two sets of surfaces are described, and they do different jobs. The Obstacle Limitation Surfaces (OLS) are established in accordance with International Civil Aviation Organization specifications adopted by Australia's Civil Aviation Safety Authority, and are generally the lower surface, protecting aircraft when a pilot is flying visually. The PANS-OPS surfaces relate to instrument procedures (source: Adelaide Airport — Airspace development and crane approvals; CASA — Objects and structures that affect aviation safety).
The practical point for an owner is that "am I under the height limit" is not one question with one answer. There is more than one surface, they sit at different levels, and which one bears on your site is not something to eyeball from a map.
Why the measurement changes the answer
This is the part that produces genuine surprises, and it is worth understanding rather than delegating blindly.
The published submission requirements ask for elevation drawings showing the maximum overall height of the structure above the Australian Height Datum, including antennae, lift over-runs and towers (source: Adelaide Airport — Airspace development and crane approvals).
Read that against how a zone height limit usually works, which is relative to the ground at your site.
A surface sits at a level above a datum, not above your dirt. So the higher the natural ground at your site, the less building height remains beneath the same surface. Two sites the same distance from an airport, in the same zone, can have materially different real ceilings purely because one sits higher. Nothing on the title says so, and nothing in the zone provisions says so.
And note what is counted: not the roof, but the maximum overall height including things bolted on top. Lift over-runs, plant, antennae. A design that fits and a design-with-services that does not is an ordinary way to fail this late.
The item owners never see coming: the crane
Here is the one worth writing down.
The published material treats cranes as an airspace matter in their own right — the airport's published service covers airspace development and crane approvals (source: Adelaide Airport — Airspace development and crane approvals; CASA — Objects and structures that affect aviation safety).
So a finished building can sit comfortably beneath a surface while the equipment used to build it does not.
That can make construction methodology an approval question, which is a category most owners have never had to think about. Whether it does on your project is for the airport operator and the relevant agencies. It bears directly on:
What the builder can price. A method that assumes a particular lift is not a neutral assumption on such a site.
The programme. An approval attached to temporary works has its own lead time and sits before the work it enables.
Which builders are suited to the site at all. Craneage constraints have consequences well beyond airports — the same category of problem is set out in crane access on constrained Adelaide sites.
Whether any of it applies to your project is for the airport operator and the relevant agencies. The reason it belongs in an owner's article is that it is discovered late by default, because nobody looks for an approval attached to a machine.
How it reaches your application
A development that may penetrate protected airspace is described as being sent to the airport for assessment by the council or the relevant state planning agency, and where an intrusion results, the airport is described as inviting CASA and Airservices Australia to assess or comment (source: Adelaide Airport — Airspace development and crane approvals).
There is a second track, and it is the one with teeth. The department states that the Act defines certain activities resulting in an intrusion into an airport's protected airspace as a "controlled activity", and requires that controlled activities cannot be carried out without approval; a person may commit an offence under section 183 of the Act, and remedial orders may be made under section 187, if a controlled activity is carried out other than in accordance with an approval (source: Department of Infrastructure — Protection of airspace).
Two further points from the same source matter to how you plan the job. Applications are made through the airport operator company, while decisions under the Regulations are issued only by authorised delegates — the Secretary may delegate functions to departmental employees and to officers or employees of an airport operator company — and such decisions "should not be pre-empted". And the department expressly names developers, builders and crane operators as parties who should check with the airport operator, or their local government, at the earliest possible stage, and who must not carry out a controlled activity without the necessary approvals (source: Department of Infrastructure — Protection of airspace).
The framework also distinguishes a temporary controlled activity — one not expected to continue beyond a stated short period, or consisting of a structure not intended to remain permanently and readily dismantled or removed — from other controlled activities (source: same). That is where a crane and a building part company: they can be different categories of activity, on different timelines, so a project may have more than one clearance to obtain.
There is also published SA material on airport referrals and pre-lodgement agreements (source: PlanSA — Pre-lodgement service: airport referrals and pre-lodgement agreements).
The shape worth carrying: this is not a question your council answers on its own. Others are brought in, and what they say bears on the outcome. If that pattern feels familiar, it is the same shape as a road authority's involvement on a main road frontage: arterial road frontage and the highways referral.
The existence of a published pre-lodgement path is the actionable part. Where a constraint is knowable before lodgement, finding out before lodgement is nearly always cheaper than finding out during it — the general cost of that difference is in the cost of delay.
What to do about it, in order
Establish whether the site is affected before you buy or before you design. This is a question with a published answer path; it does not need to wait for an application. Add it to due diligence: what to ask before buying a block of land.
Get the ground level into the conversation early. Because the surface is above a datum, your site's levels are part of the answer. That is a licensed surveyor's input, not an estimate.
Design to the overall height, including everything on the roof. Plant and services are part of the number.
Ask the construction question before tender. How the building goes up may need its own clearance.
Do not let the feasibility count storeys the airspace will not allow. A model that assumes the zone's ceiling on a site with a lower one is describing a different project: what a feasibility study should contain.
And the general lesson beyond airports: the zone is one source of constraint on a site, not the only one. Overlays and external frameworks can bind harder — which is why the ceiling that matters is always the lowest one, not the one that is easiest to look up.
Frequently asked questions
How do I know if my site is affected? Whether protected airspace affects a particular site is a question for the relevant authorities and the airport operator. There is a published referral and pre-lodgement path, and it is available before you lodge.
I'm nowhere near the airport. The surfaces extend well beyond an airport's boundary and are not intuitive from distance alone. Distance is not the test.
Does it only apply to tall buildings? The surfaces sit at levels above a datum, so what remains beneath them depends on the ground at your site as well as the height of your structure. It is not only a high-rise question.
Does my crane need approval? The department expressly names crane operators among those who should check with the airport operator at the earliest possible stage and must not carry out a controlled activity without approval. Whether your method requires one is for the airport operator and the department, and it is a question to ask before tender rather than after.
Who actually decides? Your development application is decided by the relevant authority, with the airport operator and Commonwealth agencies involved as the published process describes. Your planning consultant can tell you which parties your application engages.
Who decides what, and where Cyberate PM sits
Whether protected airspace affects the site, and what a proposal or crane does to it — the airport operator and the Commonwealth agencies involved.
How the application is assessed and referred — the relevant authority, advised by your experienced planning consultant.
Site levels and heights above datum — a licensed surveyor.
Construction methodology and craneage — your builder and their engineers.
What the resulting building costs — a quantity surveyor (QS).
Cyberate PM does none of those. We do not determine airspace, assess applications or design construction methods. We work owner-side: we get the airspace question asked at due diligence rather than at lodgement, make sure the height being tested is the overall height including plant, get the construction-method question raised before tender, and hold a feasibility built on the ceiling that actually applies. What that role covers is set out in what a development manager actually does.
Before you design to the zone's height
Is this site under protected airspace — and has that been checked with the airport operator, not inferred from distance?
What are the site's levels, and what does that leave beneath the applicable surface?
Is the height being tested the overall height, including plant and services?
Does the construction method need its own clearance?
Has the pre-lodgement path been used, or am I planning to find out during assessment?
Does the feasibility assume the zone's ceiling or the lower one?
The limit that binds your site is the lowest one over it. It is not always the one in the Code.
The governing legislation, regulations, published surfaces and referral arrangements are amended over time. Nothing here states what applies to your site. Confirm the current position with the relevant authorities, the airport operator and your own advisers before acting. Reflects publicly available material as at August 2026.
Sources
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