In my last post I introduced zoning and how to calculate the allowed housing density depending on the R codes. Well, that didn’t provide the whole picture, the minimum land is a little less than 10,000 divided by the R code
I am located in Western Australia where the planning of land use is governed by the Western Australian Planning Commission, the WAPC has allowed lower minimum land requirements then the those obtained by using the standard R codes.
The reason for this is back in the old days, blocks where measured in the Gunter Chain, literally a metal chain consisting of known Links used to measure distances. 1 Gunter Chain is equal to 20.1168 metres. Blocks of land were commonly measured out in multiples or fractions of the Gunter Chain, my 911sqm land is actually 0.9 chains by 2.5 chains. Now the problem with these imperial measurements, is it didn’t work well with the new metric system, the R codes being the later.
When the WAPC wanted to increase the housing density to allow owners of large blocks of land to build a duplex behind their existing home, at R20 many people with these 911sqm standard imperial blocks would not be able to implement this. This is one of the reasons why the WAPC decreased the minimum land to 440sqm.
The below is an excerpt from the State Planning Policy 3.1 Residential Design Codes.