The reality: no such thing as 'no approval'
Let's clear this up first — you cannot legally build a permanent granny flat in NSW without any form of approval. What people mean by 'no council approval' is the Complying Development Certificate (CDC) pathway, which bypasses your local council and goes through a private certifier instead.
CDC is a legitimate, well-established alternative pathway created by the NSW State Environmental Planning Policy (Housing) 2021. It's not a loophole — it's the government's fast-track option for granny flats that meet a strict set of criteria.
Why CDC exists and why owners prefer it
The Development Application (DA) pathway through council takes 3–6 months on average. Councils are under-resourced, applications get held up in queues, and neighbours can lodge objections that delay approval further.
CDC approval takes as little as 10 business days once your application is lodged with a private certifier. There's no council queue, no neighbour notification, and no discretionary planning assessment. If your project meets every criteria, approval is essentially guaranteed.
This speed premium is why 80%+ of new granny flats in NSW go the CDC route.
Strict eligibility — the 60m² rule and beyond
CDC pathway comes with strict, non-negotiable requirements. The critical ones: minimum 450m² block size, maximum 60m² internal floor area for the granny flat, minimum setbacks (typically 3m rear, 0.9m side, 3m from primary dwelling), retention of 24m² of usable outdoor space (min 4x4m) for the primary dwelling.
Single-storey only (two-storey granny flats require DA pathway). Height limits vary but typically 3.8m maximum. No subdivision of the title — the granny flat stays on the same title as the primary home.
If your project misses ANY of these criteria, CDC is off the table and you're back to DA pathway with council.
About 'portable' granny flats
You may see marketing for 'portable' or 'transportable' granny flats claiming no approval needed. Be cautious. Truly portable structures (like a caravan or genuinely mobile cabin) may not require approval if they meet very specific criteria — but permanent, plumbed, connected dwellings virtually always require CDC or DA approval regardless of whether they arrive on a truck.
The safest position: assume you need CDC or DA approval and design accordingly. A qualified certifier or your builder can advise on your specific block and project.