Missing middle housing refers to a lack of medium-density housing in the North American context.
The term describes an urban planning phenomenon in Canada, the United States, Australia and more recent developments in industrialised and newly industrialising countries due to zoning regulations favoring social and racial separation and car-dependent suburban sprawl.
Historic four-plex in Portland, Oregon
Police escorting a scab-driven streetcar during the San Francisco Streetcar Strike of 1907. A number of streetcar strikes broke out in the United States during the early 20th century.
Looking up 1st Ave in Seattle from Pioneer Square, 1900
A busy Los Angeles street in the 1890s showing the roads as public space not dominated by one mode of transport.
Medium-density housing is a term used within urban planning and academic literature to refer to a category of residential development that falls between detached suburban housing and large multi-story buildings. There is no singular definition of medium-density housing as its precise definition tends to vary between jurisdiction. Scholars however, have found that medium density housing ranges from about 25 to 80 dwellings per hectare, although most commonly sits around 30 and 40 dwellings/hectare. Typical examples of medium-density housing include duplexes, triplexes, townhouses, row homes, detached homes with garden suites, and walk-up apartment buildings.
An example of historic row houses in Baltimore with Characteristics of Medium-Density Housing
An example of townhouses.
Levittown, PA is an example of an established post-war suburb with single-family zoning that was created due to urban sprawl (circa 1959).
Medium Density housing being developed at in Victoria Australia.
