Granny Flat Design & Approval Services in Sydney

NSW Housing Code — Granny Flat Requirements

To qualify for CDC approval (fast track), your granny flat must meet ALL NSW Housing Code requirements:

Requirement	Standard
Minimum lot size	450m² (varies by council)
Maximum internal floor area	60m² (habitable space)
Maximum with alfresco/deck	90m²
Maximum height	8.5m
Front setback	4.5m minimum
Side & rear setback	3m minimum
Site coverage	50% maximum
Landscaping	20% of lot

Granny Flat Construction Cost — Sydney 2026

Component	Typical Cost (AUD)
Design & approval fees	$8,000 – $20,000
Construction (60m²)	$120,000 – $200,000
Total project	$128,000 – $220,000
Weekly rental (2-bed)	$400 – $600

Payback period: typically 5–8 years at current Sydney rental rates, plus $150,000–$300,000 in added property value.

Frequently Asked Questions About Granny Flat Design

What's the minimum lot size for a granny flat in NSW?

Under the NSW Housing Code, the minimum lot size for a granny flat (secondary dwelling) is 450m². Some councils allow smaller lots if specific conditions are met. Contact giantA for a free check using NSW Planning Portal data.

Can I get a CDC for a granny flat?

Yes, if your project meets ALL Housing Code requirements (60m² internal, setbacks, FSR compliance). CDC takes 10–20 days vs. 30–90 days for DA. giantA assesses which pathway is right for your site.

How much rental income can a granny flat generate?

A quality 2-bedroom granny flat in Greater Sydney typically rents for $400–$600/week. At $500/week (≈$26,000/year), a $150,000 build pays for itself in under 6 years while simultaneously increasing your property's market value by $150,000–$300,000.

How long does the whole process take?

CDC pathway: 3–6 months total (feasibility 1–2 weeks, design 2–4 weeks, CDC 2–3 weeks, construction 8–16 weeks). DA pathway: 4–9 months total.