Floor Space Ratio, or Plot Ratio
When you are buying a new house block it’s important you understand how much of the block you can build on!
One way in which NSW councils prevent Over development is by prescribing a ‘Floor Space Ration’ (FSR). The same principle applies in WA but is called ‘Plot Ratio’.
The FSR of buildings on a site is the ratio of ‘Gross Floor Area’ to Total Site Area.
Gross Floor Area is defined as – The sum of the internal floor area of each floor of a building measured at a height of 1.4 m above the floor.
It includes habitable rooms in a basement or an attic.
- Voids above a floor in 2 storey properties.
- Non habitable storage including basement areas
- Vehicular access and car parking
- Terraces / Balconies with outer walls less than 1.4 metres high, and
To calculate, you multiply the site area by the FSR ratio.
For a 800sqm site and a FSR of 0.5:1
Maximum Floor Space = 800 x 0.5 = 400sqm.
See Restrictions for more posts about what you can do on your land