Approval is the part of an extension that homeowners find most confusing, mostly because there is more than one path and the right one depends on the property, not just the work.
This is a general guide for Sydney homeowners. Requirements differ by council, zoning and site, and planning rules change, so confirm the specifics for your property with your council or a certifier before relying on anything.
The three broad pathways in NSW
Exempt development
A narrow set of minor works can be carried out without approval, subject to strict conditions on size, height, location and materials. Very little of what people call an extension falls into this category, though some small outdoor structures can.
Complying development
If a proposal meets every one of the relevant predetermined standards, it can be approved as complying development by a council or a registered certifier, which is generally a faster path than a development application. The catch is the word "every". Miss one standard, such as a setback or site coverage figure, and this pathway is not available.
Development application
Where a proposal does not meet the complying development standards, or the site has particular constraints such as heritage or a sensitive location, a development application to council is required. This involves assessment, sometimes notification of neighbours, and often a request for further information.
What is usually assessed
- Setbacks from boundaries
- Site coverage and landscaped or private open space
- Building height and number of storeys
- Overshadowing and privacy impacts on neighbours
- Stormwater and drainage
- Trees and vegetation
- Heritage or conservation area considerations
- Bushfire, flood or acid sulfate soil constraints where they apply
- Whether existing structures on the site were approved
That last point catches people out. Unapproved work built by a previous owner can need resolving before a new approval is issued.
Beyond planning approval
Planning approval is not the only paperwork. Depending on the work you may also need:
- A construction certificate before building starts
- A principal certifier appointed for the project
- Structural engineering design
- Energy efficiency assessment and compliance
- Mandatory inspections at set stages
- An occupation certificate at completion
- Home building compensation cover for residential work above the threshold value
- Sewer or water authority approval where you build near mains
Who lodges what
In practice, your designer or a private certifier normally handles the planning side, your engineer produces the structural design, and your builder works to the approved documents and calls in the inspections. Agree in writing who is responsible for each item, and who pays the fees. It is a common gap in extension quotes.
Practical advice
- Do not finalise drawings before someone has checked the planning constraints on your property.
- Ask early whether complying development is realistic. It can change your timeline substantially.
- Resolve any existing unapproved structures before you lodge.
- Keep every approval, certificate and inspection record. You will need them when you sell.
- Do not start work "while the paperwork catches up". Unapproved work is expensive to unwind.
Related reading
- What to know before building a home extension
- How long does a home extension take
- Do you need approval to build a pergola in NSW
How the pathway affects your project
The approval path is not just paperwork. It shapes the design, the timeline and sometimes the budget.
- Design. If you want the faster complying development path, the design has to be disciplined about setbacks, height and site coverage from the first sketch. Chasing a slightly larger room can push you into a full development application.
- Timeline. A development application involves assessment and often notification, so it needs to be allowed for in your program rather than assumed.
- Budget. Conditions attached to an approval can carry cost, particularly around stormwater, tree protection and driveway or footpath works.
Documents you will usually need
| Document | Prepared by |
|---|---|
| Site survey | Surveyor |
| Architectural drawings | Designer or architect |
| Structural engineering | Engineer |
| Soil classification or geotechnical report | Testing consultant |
| Energy efficiency assessment | Assessor |
| Stormwater design | Engineer or hydraulic consultant |
| Waste management plan | Designer or builder, depending on the council |
Not every project needs all of these. It is worth asking early which apply to yours, because gathering them takes time and each has a cost.
Practical sequence that works
1. Confirm the planning constraints on the property 2. Concept design tested against those constraints 3. Builder walks the site and comments on buildability and likely cost 4. Design developed, engineering commissioned 5. Approval lodged 6. Construction certificate and certifier appointed 7. Build
Skipping straight from concept to lodgement is where projects lose months, because a design that has not been tested against the site or a builder's advice often has to be revised anyway.
ORT Constructions builds to approved documents and works alongside your designer, engineer and certifier. If you are unsure which pathway your project fits, our extensions team can point you in the right direction before you spend money on full documentation.
Frequently asked questions
- Can any extension be approved as complying development?
- No. A proposal must satisfy every applicable standard. If it fails even one, such as a setback or site coverage requirement, a development application is needed instead.
- Does a builder obtain the approval?
- Usually the designer or a private certifier manages the planning approval and the builder works to the approved documents. Agree in writing who handles and pays for each step.
- What happens if previous work on the house was never approved?
- It often has to be resolved before a new approval is granted. It is better to find out at the start than after drawings are complete.
