Floor Space Ratio (FSR) — sometimes called Floor Area Ratio (FAR) — is a planning control that limits how much floor space can be built on a lot relative to the lot's area. It's one of the most powerful levers in NSW planning.
How to calculate it
FSR is expressed as a ratio. An FSR of 0.5:1 means you can build 0.5 m² of gross floor area for every 1 m² of land.
Example: 600 m² lot × 0.5 FSR = 300 m² maximum GFA. If you build two storeys, each floor can be 150 m².
Typical NSW FSR by zone
- R2 (Low Density): 0.4–0.6:1 — enough for a 3–4 bedroom house on a standard lot
- R3 (Medium Density): 0.5–0.9:1 — townhouses and manor houses
- R4 (High Density): 1.0–3.0:1 — apartments and high-rise residential
- MU1 (Mixed Use): 1.5–4.0:1 — shop-top housing and mixed-use towers
What counts as floor space?
In NSW, Gross Floor Area (GFA) under the Standard Instrument LEP typically includes all roofed floor area — including car parks on upper levels, balconies over 10 m², and any enclosed mezzanines. It excludes basement car parking (major exclusion), void areas, and plant rooms.
FSR vs height limit — which is the binding constraint?
Both apply, and whichever is more restrictive governs. On a 700 m² lot with a 1.0 FSR and a 9 m height limit, you could theoretically build 700 m² of GFA — but fitting it in three storeys with setbacks may only yield 500 m² in practice. Always model both.
Can FSR be exceeded?
Sometimes. Affordable housing contributions, design excellence bonuses, and certain SEPP provisions can allow FSR uplift in specific zones. This is why two adjacent sites can have different effective FSRs even under the same LEP.