Develpr guide

Renovations and Extensions in NSW: Do I Need Approval?

Most people start a renovation with a builder or an architect. It is usually cheaper to start with the planning controls, because they decide how far you can extend, how high you can go and how close you can build to a boundary.

This guide covers the approval side of renovating and extending a house in NSW, and what is worth checking before you spend real money on design.

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The short answer

Some renovation work needs no approval at all, some can be approved quickly as Complying Development, and larger or more sensitive work needs a Development Application through the council. Internal work that does not change the structure often falls into the first group. Extensions, second storeys and anything that changes the building footprint usually fall into the second or third.

Which one applies to you depends on the zone, the size of the lot, the floor space and height controls, how close the work sits to a boundary and whether the property has heritage, flood or bushfire issues. Those controls are property specific, so the only reliable answer comes from checking your address.

What counts as a renovation or an extension?

A renovation reworks what is already there. New kitchen, new bathroom, new layout inside the existing walls, new roof over the same footprint.

An extension adds to the building. That might be a ground floor addition at the rear, a first floor addition over the existing house, a new deck, a garage or a carport. Once you add floor area or change the external envelope, planning controls start to bite.

The distinction matters because it usually decides the approval pathway, and the pathway decides your timeline.

Could this work on my property?

A few controls do most of the work in deciding what size extension is realistic on a suburban lot.

Zoning: The zone confirms that a dwelling house and additions to it are permitted, and sets the general expectations for the area.
Floor space ratio: Many councils cap total floor area relative to lot size. If the existing house is already close to the cap, a large addition may not fit.
Building height: Height limits and, in some councils, wall height and ceiling height controls will influence whether a second storey works.
Setbacks: Front, side and rear setbacks control how close you can build to boundaries. Narrow lots feel this the most.
Private open space and landscaping: Councils generally require a minimum area of usable open space and deep soil landscaping, which limits how far a rear addition can push back.
Overshadowing and privacy: Solar access to neighbours and window placement are common issues for first floor additions, and are assessed closely under a DA.
Existing building condition: An old structure may not carry a second storey without significant work, which changes the cost before it changes the planning position.
Heritage: A heritage item or a heritage conservation area changes what is acceptable, particularly at the front of the house.

What should be checked first?

The zone and the permitted uses on the property, taken from the current local environmental plan.
The floor space and height controls, and how much of that allowance the existing house already uses.
Setbacks, private open space and landscaping requirements in the council's development control plan.
Any heritage listing or heritage conservation area affecting the site or the street.
Flood, bushfire, acid sulfate soil and land slip mapping, since these can add consultants and change the design.
Easements and sewer mains, which often sit exactly where people want to extend.
Whether the property is strata or has a covenant restricting building work.

Will I need a DA or CDC?

Complying Development

A Complying Development Certificate is a fast, standards based approval. It is only available where the proposal meets every applicable requirement and the site is not excluded. Miss one standard and the pathway is gone.

Development Application

A DA is lodged with the council and assessed on its merits, with notification to neighbours in most cases. It takes longer, but it allows design that does not fit neatly inside the codes.

Small internal renovations often need no planning approval, although building and plumbing rules still apply and structural work requires certification.

Many single storey and first floor additions on standard residential lots are designed to fit the Housing Alterations Code or the Housing Code, which allows a Complying Development Certificate. That route is quicker, but every standard must be met.

If the addition exceeds a standard, sits on a heritage or otherwise excluded site, or needs a variation, it will be assessed as a Development Application.

What can affect the opportunity?

Heritage

Conservation areas usually push work to the rear and control materials, roof form and window detailing at the front.

Narrow lots

Side setbacks on a narrow block can leave very little width for a ground floor addition.

Flooding

Flood affected land can require raised floor levels, flood compatible materials and a specialist report.

Bushfire

Bushfire prone land triggers construction standards and, for some work, additional assessment.

Trees

Significant trees on the site or next door can restrict where you can build and how you excavate.

Easements and sewer

Building over or near a sewer main needs approval from the water authority and sometimes a redesign.

Slope

Sloping sites raise excavation, retaining and overshadowing issues that add cost and complexity.

Renovating in one of these areas?

What should I do next?

Before commissioning detailed design, start by checking the property and the planning controls that apply to it. It costs very little compared with a set of drawings that has to be redone.

If the addition looks worth pursuing, a Registered Planner can review the site in more detail, flag the constraints early and help you establish the appropriate approval pathway.

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Common questions

Do I need approval to renovate my house in NSW?

Not always. Internal work that does not alter the structure or change the building footprint often falls within exempt development, so no planning approval is needed. Anything that adds floor area, changes the external walls or roof, or affects a heritage item generally needs either a Complying Development Certificate or a Development Application. Building Code compliance and certification still apply either way.

Do I need a DA for an extension?

Only if the extension cannot be approved as Complying Development. Additions that meet every requirement of the relevant housing code, on a site that is not excluded, can be certified without going to council. Extensions that exceed the floor area, height or setback standards, or that sit on heritage, flood or otherwise excluded land, are assessed by the council through a DA.

Can I add a second storey to my house?

Often yes, subject to the height limit, floor space allowance, setbacks, overshadowing and privacy impacts on neighbours. The condition of the existing structure matters too, since older footings and walls may need upgrading. Some first floor additions can be approved as Complying Development, while designs that push the standards usually need a DA.

How close to the boundary can I build?

That depends on the side and rear setback controls for your zone and lot width, plus any code requirements if you are going down the Complying Development path. Wider lots generally allow larger buildings but also require larger setbacks. Boundary walls are possible in some situations, but they need care with fire separation, drainage and neighbour impact.

Can a renovation be approved by CDC?

Yes, where the work fits the relevant code in full and the property is not excluded. That is the attraction of the pathway, since a certifier can issue the certificate without a council merit assessment. The trade off is rigidity. One non-compliant setback or an extra square metre of floor area can move the whole project into a DA.

What should I check before engaging an architect?

Get the planning position first. Zone, floor space, height, setbacks, heritage status and site constraints such as flood, bushfire, easements and sewer. A good designer will work within those controls, but you will pay for redesign if they are discovered halfway through. Knowing the realistic building envelope also makes the design brief far more useful.

How long does approval take?

A Complying Development Certificate can often be issued in a matter of weeks once the design and documents are complete. A Development Application usually takes longer because it involves lodgement, notification to neighbours, referrals and assessment. Timeframes vary between councils and depend heavily on how complete the application is when lodged.

Professional review

Get professional advice for your property

Online guides explain the general position. Your property needs to be assessed against the controls that actually apply to it.

Where appropriate, a Registered Planner can review the opportunity and help you understand what may realistically be achievable.

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Related guides

Sources

The planning position described on this page is drawn from the following sources. The requirements that apply depend on the planning controls applying to the individual property, so always confirm the current position for your site.

Planning content reviewed by a Registered Planner. This guide is general information only and is not planning advice for a specific property.

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