Building approvals for NSW

New house

Exempt: no. CDC: yes, for one or two storeys under the Housing Code. DA: usually needed when lot exclusions apply or a design standard is missed.

Knockdown rebuild

Exempt: no. CDC: often. Each part is checked separately: demolition under one code, the new house under another. DA: usually needed when heritage, lot exclusions or a non-compliant design apply.

Alterations and additions

Exempt: some minor work only. CDC: yes, when the work stays within the code limits. DA: usually needed when it adds a dwelling or changes the building class.

Second storey addition

Exempt: no. CDC: can be, if the result meets the two storey standards. DA: usually needed when height, setbacks or heritage controls rule out a CDC.

Granny flat

Exempt: no. CDC: yes, usually on lots of 450 m² and up. DA: usually needed when the lot is smaller or the design is outside the standards.

Dual occupancy

Exempt: no. CDC: possible under the LRHD Code. DA: usually needed when the lot is under the minimum size, heritage applies or a standard is missed.

Swimming pool or spa

Exempt: no. CDC: yes, if located behind the building line. DA: usually needed when the waterline would sit closer than 1 m to a rear or side boundary.

Shed or outbuilding

Exempt: often, if small and within the limits. CDC: yes, for larger sheds that meet the code. DA: usually needed when the size or siting goes past the code.

Carport or garage

Exempt: small carports only. Garages never. CDC: yes, for garages and larger carports. DA: usually needed when the design or site falls outside the code.

Decks, pergolas, retaining walls

Exempt: often, if within the size and height limits. CDC: yes, for bigger decks and taller walls. DA: usually needed when the structure falls outside both sets of rules.

Changes on the way

The Building (Approvals and Practitioners) Act 2026 passed Parliament in August 2026. It will move building approvals out of the planning Act into a new law. It only starts once regulations are made, and no date is set. Until then, today's system still applies.

Dual occupancies after the housing reforms

From 1 July 2024, the state allowed dual occupancies and semi-detached homes on all land zoned R2 for low density housing, statewide. This was the first stage of the state's Low and Mid-Rise Housing Policy.

Stage two followed on 28 February 2025. It promotes dual occupancies, terraces, townhouses and low-rise apartments on residentially zoned land close to 171 selected town centres and rail or light rail stops, measured as up to 800 metres on foot. These areas sit in Greater Sydney, Newcastle and the Lower Hunter, Illawarra-Shoalhaven and the Central Coast.

Some land is left out, including land with high bush fire or flood risk, land containing a heritage item, and land near dangerous goods pipelines or under high aircraft noise. Being permitted does not decide the route. A project may still qualify for a complying development certificate (CDC), or need a development application (DA), based on the lot and its plans.

Building in a mine subsidence district

Parts of NSW are declared mine subsidence districts. Building or subdividing in one requires Subsidence Advisory NSW to approve the work before it starts, although some minor works, such as small carports, decks and fences, are exempt. The NSW Planning Portal shows whether a property falls within a district and which guideline applies to it.

The assigned guideline sets the approval path. Councils and certifiers may approve work without a referral on properties assigned Guidelines 2, 3 and 3A, plus 6 and 8. On properties assigned Guideline 1, 1A, 4, 5 or 7, the work must be approved by Subsidence Advisory itself. A DA in a district is treated as integrated development, so council refers it on.

Subsidence Advisory approves applications that meet the guideline within 7 calendar days of receipt, and makes merit decisions within 40 calendar days unless more information is needed.

Bush fire prone land and the DA route

Complying development on bush fire prone land is limited to sites with a bushfire attack level (BAL) of BAL-LOW, BAL-12.5, BAL-19 or BAL-29. Sites rated above that need a DA instead, and council cannot approve development on bush fire prone land unless it complies with the bush fire planning guidelines published by the Rural Fire Service.

For a single new house, the applicant can show compliance using the single dwelling kit published by the Rural Fire Service (RFS), or a certificate from a qualified consultant. The BAL can only be endorsed by council or by a bush fire consultant holding accreditation. A DA for one dwelling is not integrated development, whereas a residential subdivision requires a safety authority issued by the RFS Commissioner.

State agency referrals from July 2026

Some DAs need input from a state agency, for example where bush fire or mine subsidence risk triggers a referral. Any DA lodged from 1 July 2026 onward has these referrals handled by the Development Coordination Authority, a single point of contact within the state planning department.

Applicants do not usually deal with it directly. Council makes the referral and remains the contact for updates. The authority and other bodies generally have 28 calendar days to respond to a local referral, with the clock paused if more information is requested. DAs lodged before 1 July 2026 stay under the earlier arrangements.

Can work be approved after it is built?

Neither a DA nor a construction certificate (CC) can approve building work that was carried out without one. A CC only covers future work, and council cannot approve completed works through a DA. A DA can sometimes deal with a use that started without approval, but not the structure itself.

For a structure already built, the usual option is a building information certificate from council. It limits certain council orders, yet it approves nothing, and council can still issue a fine or start legal action over the unauthorised work.