Can I build complying development on my block?
Written by Shea Cullen, architect, for Dudils.
Complying development is the fast approval path in NSW, and whether your block can use it turns on a short list of gates: the zone, the lot size and width, heritage, and a handful of mapped constraints. Type an address and the Site Checker tests the gates it has maps for, for a new house, a granny flat and a dual occupancy, and tells you which ones it cannot read. It is a first look, not a certificate: only an accredited certifier or the council can say yes.
NSW addresses only. Free, and no sign up.
Can I build complying development on my block?
You can if the block clears every gate in the code for what you want to build, and the design then meets every one of that code's standards. The Site Checker reads the zone, the lot area, the street frontage, the heritage map, land reservations, acid sulfate soils, the foreshore line, the flood maps and the bush fire prone land map, and sorts each development type into looks possible, needs checking or looks ruled out.
Some gates are on no public map, so they always need checking: registered easements, draft heritage listings, contaminated land and the width of the lot at the building line, which is where the front wall of the house sits rather than the street boundary we can measure. Your council's section 10.7 planning certificate and your certifier settle those.
What is complying development, and how is it different from a DA?
Complying development is building work that meets a fixed set of standards in a State policy, so it can be approved with a complying development certificate (CDC) instead of a development application (DA). The standards are in the Codes SEPP, with granny flats in the Housing SEPP.
A DA is assessed on merit by the council against its local environmental plan (LEP) and development control plan (DCP), and it can bend a control where the design justifies it. A CDC cannot bend anything. If the design misses one standard by 100 mm, it is not complying development, and the choice is to redesign or lodge a DA.
What stops a block from qualifying?
Land that holds a heritage item, or sits in a heritage conservation area, cannot take a new house, granny flat or dual occupancy as complying development (Codes SEPP clauses 1.17A and 1.19). Nor can land reserved for a public purpose, Class 1 or Class 2 acid sulfate soils land, the foreshore area, land an LEP marks as environmentally sensitive, coastal hazard land, significantly contaminated land or land in the 25 ANEF aircraft noise contour.
The Housing Code then needs the lot to be in Zone R1, R2, R3, R4 or RU5, at least 200 m² and at least 6 m wide at the building line (clause 3.1), and no building can go over a registered easement (clause 3.2). Where only part of a lot is excluded, complying development can still go on the rest.
Can I build a granny flat or a duplex as complying development?
Often, yes, on a big enough block. A granny flat needs Zone R1, R2, R3 or R4, a lot of at least 450 m², and a frontage at the building line of 12 m on lots up to 900 m², 15 m up to 1,500 m² and 18 m above that (Housing SEPP section 54 and Schedule 1). It can be up to 60 m², or more where your LEP allows.
A dual occupancy (a duplex) comes under the Low Rise Housing Diversity Code. It needs Zone RU5, R1, R2 or R3, a lot of at least 400 m² or the LEP's dual occupancy minimum if that is larger, and 15 m of width at the building line, or 12 m where the car parking is reached only from a second street, a parallel road or a lane (clause 3B.8). It cannot be complying development on a battle axe lot or on land without sewer (clause 3B.2). Since July 2025 the NSW Housing Pattern Book designs add another complying route for dual occupancies and terraces in R1, R2 and R3.
Does bush fire prone land or a flood map stop complying development?
Neither rules it out on its own. On bush fire prone land, complying development is possible unless the building site is BAL-40 or the flame zone (Codes SEPP clause 1.19A), and a lower Bushfire Attack Level brings extra standards for construction, water supply, gas and access. The Site Checker shows the RFS map category but cannot give a BAL. A bush fire consultant recognised by the RFS, or the council, works that out.
On a flood control lot, complying development can go only on parts of the lot that the council or a hydraulic engineer certifies are not floodway, flood storage, flow path, high hazard or high risk, and the house must meet flood floor level and construction standards (clause 3.5). The flood reading shows what is mapped. The section 10.7 certificate states whether the lot is a flood control lot, and the maps cannot tell you which parts are floodway. The Pattern Book route is closed on both bush fire prone land and flood control lots.
How long does a CDC take, and who issues it?
The NSW Department of Planning says a CDC can be issued in as little as 20 days, which includes 14 days of notice to neighbours. A registered (accredited) certifier or the council issues it, and you choose which.
The certifier checks the plans against every standard, so the certificate is only as quick as the drawings are complete. Ask your designer to set the house out to the code's setbacks, height and floor area from the first sketch. The envelope on the Site Checker diagram uses the Housing Code setbacks for a new house, which is a fair first test of how much of the block a complying house could cover.
Can I use complying development on my block? Check any NSW address, free.
NSW addresses only. Free, and no sign up.
What else do people ask?
Can my neighbours stop a complying development certificate?
Neighbours are notified before a CDC is issued, but a CDC is not a merit decision. A complaint only matters if it shows the design misses a standard in the code.
Do I need a section 10.7 planning certificate for a CDC?
Expect your certifier to ask for a current one. It is the council's statement of whether the land is a heritage item, in a conservation area, a flood control lot or affected by other controls that decide whether complying development is possible.
Is the Site Checker result a complying development check I can rely on?
No. It tests the gates we have public maps for and lists the ones we cannot read. Only a certifier, working from the section 10.7 certificate, a survey and your plans, can decide that a design is complying development.
Where does this information come from?
The Site Checker reads public maps. It is not a section 10.7 planning certificate, a flood certificate, a bushfire attack level assessment or a survey, and a map can be out of date for your lot. Confirm anything you rely on with council or the relevant authority before you buy, design or build. Nothing on this page replaces advice from your certifier, engineer, lawyer or your own designer.