Can I Build a Granny Flat in NSW? The 5-Minute Checklist (CDC)
A granny flat (or secondary dwelling) is one of the best ways to add value to your Sydney property, create space for family, or build a new income stream. But the biggest question is: can you actually build one on your block?
While you can always try a complex Development Application (DA), the fastest, cheapest, and most certain path is a Complying Development Certificate (CDC).
A CDC is a “fast-track” approval that’s based on a “black and white” set of rules. If your project ticks all the boxes, a private certifier can approve it in weeks, not months. But how do you know if you qualify?
Use this 5-minute checklist to find out if your property is a good candidate for a granny flat CDC.
What’s a Granny Flat CDC? (And Why You Want One)
Think of the CDC as a “tick-a-box” approval. It’s managed by the State Environmental Planning Policy (SEPP), meaning it bypasses most local council-specific rules.
- DA (Development Application): A slow, subjective process where your local council assesses your plan’s “merits.” Can take 3-6+ months.
- CDC (Complying Development Certificate): A fast, objective process. If you meet the rules, a private certifier must approve it. Can take as little as 2-4 weeks.
For a granny flat, you want the CDC path if you can get it.
The 5-Minute Granny Flat Checklist (CDC)
Answer these 7 “Yes/No” questions to see if you qualify.
1. Is your property zoned correctly?
- Yes: My land is zoned R1, R2, R3, R4, or R5. (These are standard residential zones).
- No: My land is zoned R-something else, E (Environmental), or RE (Recreational).
(If ‘No’, you almost certainly can’t use CDC and will need a DA.)
2. Is your property big enough?
- Yes: My block of land is at least 450m².
- No: My block is smaller than 450m².
(If ‘No’, CDC is not an option. A DA might be possible, but it’s very difficult.)
3. Is your property wide enough?
- Yes: My block is at least 12 metres wide when measured at the “building line” (the front wall of your existing house).
- No: My block is narrower than 12m.
(If ‘No’, CDC is out. You will need to try a DA.)
4. Is the granny flat itself the right size?
- Yes: The proposed granny flat has a floor area of 60m² or less. (This does not include verandahs, patios, or carports).
- No: I want to build a larger 80m² flat.
(If ‘No’, it is not a “secondary dwelling” and cannot be a CDC. 60m² is the magic number.)
5. Do you have enough “open space” left?
- Yes: After building the granny flat, I will still have a certain amount of landscaped “open space” remaining on my block (the amount varies, but it’s usually 20-30% of your total block size).
- No: The new flat will mean my entire backyard is covered by buildings, paving, or a pool.
(If ‘No’, you won’t meet CDC rules and will need a DA to argue your case.)
6. Can you meet the setbacks (distances from fences)?
- Yes: I can position the granny flat…
- 3.0 metres from my rear fence.
- 0.9 metres from my side fences.
- 3.0 metres away from my main house.
- No: I need to build it right on the fence line or closer than the rules allow.
(Note: Setbacks can change based on building height. If ‘No’, you must use a DA to ask for a variation.)
7. Is your property “clear” of restrictions?
- Yes: My property is NOT heritage-listed, in a high-risk bushfire zone (BAL-40 or Flame Zone), or in a high-risk flood control area.
- No: My property is on one of those restricted lists.
(If ‘No’, you are almost certainly excluded from the CDC path and must lodge a DA.)
What to Do Next
If You Answered “Yes” to All (or Most) Questions…
Congratulations! Your property is a prime candidate for the fast-track CDC path. You haven’t wasted months hoping for a DA. The next step is to get a professional to confirm everything.
If You Answered “No” to One or More Questions…
Don’t panic! This does not mean you can’t build a granny flat.
It simply means the “fast-track” CDC path isn’t for you. Your project will need to be lodged as a Development Application (DA) with your local council. A DA is more flexible, and a council can vary rules (like setbacks or size) if you have a good reason. However, this process requires a much more detailed set of plans, justifications, and professional management.
Stop Guessing. Let’s Find Out For Sure.
A checklist is a great start, but the only way to be 100% certain is with a professional assessment as this is for an approximate idea
Before you do anything else, you need two things:
- A Section 10.7 Planning Certificate from your council (this confirms your zoning and restrictions).
- An expert opinion.
At JJ Drafting, we specialise in granny flat approvals. We can review your 10.7 Certificate and your site to give you a clear, definitive answer: CDC or DA.
We will then design a high-quality, practical granny flat that is perfectly suited to your block, your budget, and the correct approval pathway.
Ready to add value to your property? Contact JJ Drafting today on 0414 71 75 41 or 1300 977 804 or email enquiries@jjdrafting.com.au for a free quote. We’ll make your granny flat project simple, clear, and successful.
**** PLEASE NOTE THIS IS A GUIDE ONLY ****
mistakes can happen, please feel free to contact us