Toronto’s housing supply consists of two extremes — a downtown core of high-rise condos surrounded by low-rise neighbourhoods of single-family houses. This results in the well-documented “missing middle” problem; a scarcity of modest urban density. But the city, where it is currently much easier to build a house than a duplex, triplex or fourplex, also has a “missing little” problem.

According to Toronto’s zoning by-law, a single detached house can be built to a maximum building depth of 17 metres, whereas a multiplex (defined as a building with up to four dwelling units) is limited to a depth of 14 metres. Side yard setback regulations follow a similarly penalizing pattern. These rules raise an important question: Why are we allowing buildings for one household to be bigger than those for multi-generational households and buildings accommodating several households?