Medium-density housing

In the U.S. most medium-density or middle-sized housing was built between the 1870s and 1940s[10] due to the need to provide denser housing near jobs. Examples include the streetcar suburbs of Boston which included more two-family and triple-decker homes than single-family homes,[10] or areas like Brooklyn, Baltimore, Washington D.C. or Philadelphia[10] which feature an abundance of row-houses. This type of housing, once an affordable option for rental or homeownership has turned into luxury development due to the rising land and construction costs of nearby developments.[11] Before WW1 the Garden-city movement had become an increasingly popular method for planning neighborhoods. As the U.S. began experiencing a housing crisis for war workers, it began a mass production of housing that followed the Garden-city form. This greatly impacted development patterns across the United States until the Great Depression. During the Great Depression the U.S. government passed the National Housing Act of 1934 to create the Federal Housing Authority with the goal of providing more federally backed loans to Americans so they could purchase homes. This led to the White Flight of the 1940s because many White Americans were able to move from urban cities to homes at the outskirts of the city, as well as purchase cars. This furthered the suburbanization of America which led to the increase in home sizes, land use, automobile use and contributed to suburban sprawl.[12] Neighborhoods were no longer built to human scale, but rather built to accommodate larger developments; in the suburbs this meant larger single family homes and wider roads for cars and in the city high-rise apartments.[12]

Levittown, PA is an example of an established post-war suburb with single-family zoning that was created due to urban sprawl (circa 1959).

In the 1960s architects identified a stark difference between neighborhoods created by high-rise development and suburban sprawl, and realized there was a need for more medium-density or middle-sized housing to bridge the gap between cities and suburbs.[5] Architects and developers started building cluster housing to address this gap in housing but these kinds of developments weren't marketed towards low-income residents in need of housing.[5] Due to the recession in the 70's President Nixon issued a moratorium on government funding for low-income housing.[5] Medium-density or cluster development were framed as an undesirable but necessary solution to the housing crisis by TV programs and newspapers.[5] Established suburbs of the postwar-era had created distinctions between home and work life, also distancing themselves from their neighbors.[5] The introduction of medium-density housing into established suburbs was not allowed due to exclusionary single-family zoning and because it was viewed breach of family fundamentals that had been established with suburban living.[5] Medium-density, cluster or middle-sized housing was referred to as an inadequate, makeshift substitute for those who couldn't afford suburban living.[5] This perception of medium-density or middle sized housing has been thought to be fueled by irrational fears of density[12] and wanting to keep low-income residents out of suburban neighborhoods.[5] This led to the decrease of medium or middle-sized housing in America, referred to as Missing Middle Housing.

Many traditional types of housing developed prior to car-based cities were at comparable densities, such as the terraced (row) or courtyard housing found in many parts of the world. The inner suburbs in many Australian cities and those activity centres developed during the late Victorian suburban boom have examples of medium density housing. Since the 1960s, many Australian states have encouraged urban consolidation policies which have facilitated the construction of medium density housing. The debate around medium-density housing arose during the Garden Suburbs movement. The first studies on medium-density housing happened during the 1960s during the post-war housing boom, focusing on housing consumption rather than sustainability and affordability.[13] In the 1970s more studies performed investigated barriers to producing medium-density housing and attributed them to planning. Studies in the 1980s and 1990s however focused more on perceptions of medium-density housing and how it is designed.[13] Despite positive perceptions of medium-density housing from those who actually lived in it, people living in less dense housing perceived it as negative.[13]

Townhouses in Hobsonville, Auckland.

In New Zealand housing has historically focused on a semi-rural or suburban density and has experienced extensive suburban sprawl.[14] Several reports have highlighted the need for medium-density housing in New Zealand as a means of providing affordable sustainable housing.[15]