Here is single detached under a microscope, including completed but unabsorbed units:
While single detached starts and completions are below levels seen before the recession, units under construction and unabsorbed inventory are both higher. These datasets do not indicate where single detached units are being built, but many if not most will be on previously unoccupied land, the remainder will be infill. Rumours of "strength" in "single family" house prices in certain areas do not align well with these data.
Another point to make is that CMHC-reported "single detached" will include houses with secondary suites. Houses with occupied secondary suites that were counted as "single detached" by CMHC and municipalities are counted as multifamily by Statistics Canada when performing census dwelling counts. Interestingly those same dwelling counts will count laneway houses as "single detached" (which of course they are since they share no walls, ceilings or floors with anyone but the mice).