You haven't been keeping up with the changes in the law. There is no such thing as single family zoning inside cities in BC anymore.
The provincial government made it so that essentially any property in a municipality over 5000 people is allowed to have 3 units if it's under 280 square meters, or 4 units if it's over 280 square meters.
If it's greater than 280 meters near frequent bus service(15 minutes or better during daytime hours), it goes up to a minimum allowance of 6 units.
Any property within 800 meters of a rapid transit exchange or 400 meters of a regular transit exchange also gets automatic zoning allowing a massive upgrade to number of stories for condo/apartment buildings.
Again, there's no shortage, there's plenty of housing available, it's just that there's a lot of over-housed people who are hogging properties they don't reasonably need.