Here is a mapping, from the University of Toronto's School of Cities, showing the number of "closed" building permits issued in Toronto between 2013 and 2023 for both rear-yard suites (laneway houses and garden suites) and secondary suites (like basement apartments).
A "closed" building permit probably means that construction is complete. However, it is not uncommon for a permit to inadvertently remain open. This happened to me with Mackay Laneway House. The permit was supposed to be closed, but it wasn't.
So here's the same mapping with open (i.e. active) permits also turned on:
Three things immediately stand out:
Secondary suites seem to be somewhat evenly distributed across the city.
Rear-yard suites are heavily concentrated in the older areas of the city, flanking the downtown core.
North Toronto is wealthy and isn't having either of these housing typologies.
Looking at these mappings, it probably seems like a decent amount of new housing. But that's not really the case:
From 2013 to 2023, Toronto issued 2,209 building permits for secondary suites (1,525 have been closed and 684 remain open as of December 31, 2023).
And from 2020 to 2023, Toronto issued 898 building permits for rear-yard suites (192 have been closed and 706 remain open, which does suggest some increased adoption). Rear-yard suites only became permissible in 2018, which is why the date range is shorter.
To be fair, I would imagine that many secondary suites get built without a building permit. So I think the above number is probably underestimating actual supply. But even still, it doesn't change the conclusion: A lot more needs to be done to increase the supply of new housing in Toronto.