Rapid post-war development in North America has created a tale of two densities and extremes of housing that have dominated the cityscapes of the continent's biggest cities. Highrise condominiums and apartments are fulfilling a demand for comparably inexpensive living within urban enclaves, while single-family housing has exploded in the suburbs, creating a built form characterized by large lots and automobile dependency. But the sweet spot in the middle has been lost in the shuffle, leaving little room for the gentle densities that defined neighbourhoods before the Second World War.

Missing Middle Housing types, image via Opticos Design

This so-called "Missing Middle Housing" is what city builders and urban planners are striving to bring back into the fold. These multi-unit housing types — duplexes, fourplexes, townhouses, and courtyard apartments — generally have a similar size footprint to single-family dwellings. Because of their comparable physical dimensions, Missing Middle Housing can be comfortably integrated into blocks that are historically and predominantly occupied by single-family homes. The moderate densities these building typologies achieve can support an amenity-rich and walkable environment serviced by public transit. They play a massive role in helping cities, like Edmonton, reach their infill and density development targets.

Townhome development in Toronto, image by Marcus Mitanis

Some of America's most vibrant and hip up-and-coming communities embrace this concept. Changing demographic trends have shown that youth and seniors cherish easy access to services and amenities available in compact and transit-oriented neighbourhoods. Millennials are driving less than their predecessors, and aging baby boomers increasingly want to "age in place," according to the American Association for Retired Persons. The convergence between the two cohorts is pushing a narrative for more diverse housing options. 

Missing Middle Housing in Toronto, image retrieved from Google Street View

An average physical footprint and small unit sizes can make Missing Middle Housing a lucrative prospect for developers, but outdated zoning and land use regulations often bog down the approvals process. Governments that are hoping to ease the housing crunch and prevent priced-out millennials from fleeing the city are gradually amending their planning policies and codes to allow for intuitive fixes like laneway housing and "pork chop lots."

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