Pat Hanson of gh3* is absolutely right with her comment, here, about why we are seeing more windowless bedrooms being built in Toronto:
In much the same way, some of Toronto’s development policies encourage windowless bedrooms. “I don’t think it’s driven by cost,” says architect Pat Hanson, a founding principal of gh3* and a member of Waterfront Toronto’s Design Review Panel. “It’s driven a lot by building forms. Where you find a lot of these inboard bedrooms is in the mid-rise type.” The requirements to step back mid-rises on an angular plane, she adds, forces the developers to populate their projects with very deep units.
This condition is being driven by building forms and by overall housing affordability.