This map shows the percentage of occupied dwelling units that are "Single Detached". Compare that to the corresponding maps based on 2016 data and based on 2006 data. Stats Canada defines a dwelling as Single Detached as

A single dwelling not attached to any other dwelling or structure (except its own garage or shed.) A single-detached house has open space on all sides, and has no dwellings either above it or below it.

Thus it differs from the definition used in many municipalities and zoning codes that often permit basement suites. In the context of Vancouver's zoning laws, RS zones allow for one basement suite and a laneway house for an RS-zoned property. For Stats Canada, an RS-zoned house without any basement suite is classified as Single Detached, if it has one basement suite it is classified as Duplex. If it has a laneway house, the laneway house would be classified as a separate Single Detached property. This leads to significantly different counts of single detached homes, depending on the definition. By the City's definition, Vancouver has about 75k Single Detached properties, Stats Canada lists 47,530 in the 2011 census making up 18% of dwelling units, down from 48,365 in the 2006 census comprising 19.1% of dwelling units.

This difference allows us to observe the "multi-family creep" that is happening in RS zoned neighbourhoods. On the East Side in Vancouver there are hardly any areas left with over 50% Single Detached dwelling units. The only larger area with a percentage of Single Detached houses above 90% is along the Granville Street corridor south of Shaughnessy. It will be interesting to monitor this for changes in the 2016 census.

Montreal stands out among major Canadian cities with hardly any single detached dwellings throughout, making up only 7.5% of the city's dwelling units. Toronto comes in with 26.2% of Single Detached dwelling units, Calgary tops the list with 58.7%, even edging out Edmonton at 51%.

For the City of Vancouver we can compare this to assessment data. Single Family Homes as defined through BCAssessment data are prevalent throughout large portions of the city, but many of these are classified as duplexes or even "apartments with less than 5 stories" in census data. We can mix the assessment data with the census data to see how well SFH and Duplex counts combined match up, or we can focus on census areas where all residential units from BCAssessment data are single family properties and compare the census unit and assessment lot counts for these areas.