With reporting on the new census numbers gaining traction, and now Mayor Robertson picking up on single family neighbourhoods losing population we thought it is time to crunch some numbers. Why does it need number crunching? All the reporting so far is based on looking at CT (Census Tract) aggregates, like e.g. in the map shown and linked to the right. But there is actually no single CT in the City of Vancouver that only contains RS zoning.
A little over a year ago we ran some analysis on teardowns of single family homes in the City of Vancouver. We used the City of Vancouver open data to understand why some single family homes got torn down and other’s don’t. Relying entirely on open data, there were some important questions that could not be answered. So together with Joe Dahmen at UBC’s School Of Architecture And Landscape Architecture we came back to the question and folded in transaction data from BC Assessment to add some more details and rigor.
RT is Vancouver’s zoning for duplexes. Over time, various areas have been zoned to allow duplexes. Examples are Kits Point, much of Point Grey Road reaching up to Broadway, much of Granview-Woodlands, parts of Mount Pleasant and many other areas. Recently I have had some interesting conversations on Twitter regarding RM-6 and over BBQ dinner about RT-7. Then the Granview-Woodland plan passed by council, and it contains a curious provision of reducing the outright FSR for the RT-zoned properties from 0.
Recently the question around the amount of space taken up (exclusively) by single detached houses has show up on my Twitter feed citing that SFH take up 70%, 66%, and 57%, 56% (timestamp 3:50). I personally have thrown in 34% as a contender. And, just for the fun of it, by the end of this post I will have thrown 33% and 28% and my favorite, 81%, into the mix.
I was curious how the physical parameters of Single Family Houses changed over time. Using the assessment dataset merged with the land use dataset allows to fairly accurately pick out single family houses, and also holds the age of most properies. Together with the City of Vancouver LIDAR-generated building dataset that I have played with before we can look at physical building parameters. The city dataset is a little coarse, it only contains the main building and does not map things like garages.