The Seattle Times has an article up about “widespread single-family zoning” that will feel familiar to many here in Toronto who, I know, are having similar conversations about the amount of land dedicated to low-density housing.
The article, by Mike Rosenberg, estimates that 49% of all developable land in Seattle is dedicated to single-family housing; that 8% is dedicated to multi-family housing; and that another 8% is dedicated to commercial and mixed-use buildings. The rest of the land is institutional, open space, vacant, and so on.
Of all the residential lots in the city, the estimate is that 69% of them are occupied by single-family houses. This is compared to 1% in Manhattan.
I tried to reverse engineer the 69% based on the land use areas in the article, but the math didn’t quite add up. In any event, the argument here is, of course, that single-family homes are too expensive in Seattle and that the city needs more land available for multi-family housing.
Housing supply is no doubt important, but looking at the above chart, having a low, or lower, percentage of residential land dedicated to single-family housing doesn’t seem to necessarily guarantee affordable housing.