Granny Flats Sydney
Secondary dwellings from 40sqm to 60sqm across Greater Sydney. CDC approval managed as standard. Fixed price contracts available for standard designs.
Request a QuoteState Property Development builds granny flats (secondary dwellings) across Greater Sydney. NSW Builders Licence 355555C. $20M public liability. We manage the design, CDC approval, and construction under one contract — so there’s a single point of accountability from site assessment to occupation certificate.
Before we quote on anything, we check your lot against the NSW Housing Code requirements. Minimum 450sqm lot size. Maximum 60sqm floor area for the secondary dwelling. Setbacks, site coverage, and height limits that vary by zone. There is no point getting excited about a granny flat before confirming your site qualifies — we do that first.
NSW Granny Flat Rules — Key Numbers
- Minimum lot size: 450sqm in most residential zones under the NSW Housing Code
- Maximum floor area: 60sqm for the secondary dwelling
- Approval pathway: CDC via private certifier (10–20 days) in most cases
- Height limit: 8.5m maximum to roof ridge in standard residential zones
- Setbacks: 3m rear for single storey; vary by council for side boundaries
Cost to Build a Granny Flat — Sydney 2026
- 40sqm studio: $85,000–$140,000 in construction
- 50sqm one-bedroom: $110,000–$175,000
- 60sqm one or two-bedroom: $120,000–$220,000
Design and CDC fees add approximately $8,000–$20,000. Site-specific conditions — slope, soil type, distance to existing sewer connection — affect construction cost. We assess site conditions before quoting.
How Long It Takes
Design: 4–8 weeks. CDC approval: 10–20 days. Construction: 12–16 weeks. Occupation certificate: 1–2 weeks. Total project time: typically 5–8 months from when you give us the go-ahead to when the keys are handed over.
Granny Flat FAQs
$85,000–$140,000 for a 40sqm studio. $110,000–$175,000 for 50sqm one-bedroom. $120,000–$220,000 for a 60sqm one or two-bedroom. Design and CDC fees add $8,000–$20,000. Full cost guide here.
450sqm minimum lot area under the NSW Housing Code (SEPP Housing) for most residential zones. Maximum 60sqm floor area for the secondary dwelling. We check your lot against current requirements before quoting — there’s no point proceeding if your site doesn’t qualify.
Most granny flats proceed as Complying Development (CDC), approved by a private certifier in 10–20 days without going to council. Sites that don’t meet CDC requirements — unusual lots, heritage overlays, flood-affected land — require a council DA, which takes 40–90+ days.
12–16 weeks of construction once CDC is approved. Total project time from decision to keys: typically 5–8 months (design 4–8 weeks + CDC approval 2–4 weeks + construction 12–16 weeks + occupation certificate 1–2 weeks).
Yes. Secondary dwellings approved under the NSW Housing Code can be rented out independently of the main dwelling. An occupation certificate is required before rental can commence. Some council-specific DCP provisions previously restricted independent letting, but these were largely overridden by state policy from 2023.
Granny Flat Enquiry — Sydney
Site assessment before you commit to design. NSW Licence 355555C. $20M public liability. Jay responds within one business day.