Cities are not static open-air museums; their shape and size evolve with time. Because populations grow, it is relevant to understand how cities can and must adapt to an ever-increasing pressure in housing demand and rising cost of urban living. Healthy cities change to accommodate economic and cultural realities of their inhabitants. Cities, like forests, must grow to survive. But how that growth happens makes the difference to which individuals will find a home to thrive.
There are different formats on how cities grow in size. The typical historic pattern or urban growth followed a concentric circle around denser areas. The city expanded around a central hub of economic activity where the most valuable properties were located. The closer each property was to the core, the higher its value. Large urban areas like New York and Chicago followed this pattern of growth early in their history.
Transit infrastructure affected urban growth patterns in the modern era. Through transportation hubs, cities grew in axial patterns following the implementation of train stations and other methods of mass transit. The effective movement of people and goods to and from the city center expanded the radius of what was considered urban areas. Residential and commercial projects developed along those transportation lines which resulted in increased property values on each transit hub.
The distribution of neighborhoods and suburbs in Washington, DC is an example of this type of axial urban growth. A network of horsecar trolleys started operating in 1962 with horsecars and were transformed to electric in 1888; the development of middle-class residential neighborhoods followed these lines that extended well into Virginia and Maryland. This above-ground system was finally dismantled in 1960. Bus lines and the subway partially replaced the historic above-ground lines but essentially continue to emphasize urban growth in an axial pattern.
Different from concentric or axial, sector growth is the pattern of urban expansion that follows individual developments. It is a combination of the axial pattern along with specific magnet projects. The growth happens outward from the city and concentrates uses by type. American development of zoned maps follows this pattern of growth, by type of use and shape of buildings. University campuses create sector growth by concentrating new uses, like higher education, and attracting students, professors, and staff to a clustered area. Demand of services and housing increases in sectors of the city heavily influenced by long-term and large developments.
American cities have followed a combination of growth patterns listed above. However, recently, there has been a reversal on urban growth. Historically cities grew outward buoyed by affordable land and accessible highways. In recent years, distant suburban developments burdened families with long commutes and the social cost of car dependency. The current market demands smaller homes near activity centers that result in new projects in more convenient locations to daily activities.
Innovative urban housing and production
Cities do not grow in an abstract manner. Their expansion materializes in the addition of buildings, infrastructure, and increased demand for services. So how does new housing happen?
Traditionally, new housing occurred as new buildings in empty land. A private developer would purchase undeveloped land on the outskirts of the city, normally the suburbs, and build single-family homes. Supported by highways, shopping malls, and the suburbanization of services, this type of housing development increased distances and emphasized a car-dependent culture. The units developed maximized size and value while creating homogeneous results of single-family homes. Lack of variety in design and construction is cheaper to design, build, and finance than heterogeneous housing. This development of housing growth excludes affordable units and limits the models of houses available for purchase. Because land near urban centers is becoming scarce, the availability of acreage to continue this type of housing growth is unsustainable from a social and economic perspective.
Aside from suburban and exurban growth, urban residential growth also happens with the replacement of existing units. In these areas, developers buy outdated older homes, demolish them, and build a new one from scratch. The tangible consequence of this type of project is the replacement of a smaller, affordable unit with a larger, more expensive one. The cost of buying a home in the same lot increases and the availability of new affordable housing is reduced. Current zoning and financial models encourage the replacement of single-family housing but discourage the conversion into multiple units on the same lot.
Aside from replacement of individual homes, new housing units are created through large-scale multistory projects. Due to the impact on established neighborhoods, this type of project requires coordination between city and developers. They tend to be located in high traffic corridors and result in the densification of a small area. Existing neighbors have little to no influence in the remediation measures that a high-impact project will have. The main benefit of large-scale residential projects is the potential to revitalize disinvested areas providing density to retail and services options on the ground floor, like a grocery store or a day care center.
Aside from large-scale projects, another contributor of new housing can be found in the addition of middle-height housing projects. These types of developments, up to four stories, introduce middle density to neighborhoods. The visual and environmental impact of these projects is limited to the existing streetscape and contributes small-scale retail space on the ground floor, like restaurants and cafes.
An example of this type of middle-scale project can be seen in Petworth, a neighborhood in north-west Washington, DC. The main roads that traverse the neighborhood are converting existing townhouses while providing infill units. The new projects blend with the neighboring structures and allow for existing housing units to be preserved in the surrounding smaller streets. These types of projects are contributors to the local economy by providing ground floor commercial space to small business owners.
Aside from multiunit residential projects, an innovative option to add new housing in the city is the creation of units within existing homes. Located in backyards, basements, and attics, these types of units do not require public participation and have little to no impact on the streetscape. Additional dwelling units contribute one or two extra units per lot by optimizing the use of land in low-density neighborhoods. They illustrate a private solution to the public housing deficit. The aesthetic impact of these types of housing is negligible to the urban environment. They do not provide retail fronts, but the spaces open the possibility for small businesses such as professional services to grow within residential neighborhoods. Detached accessory structures are ideal to use as a dwelling, an office, and small industries like a bicycle repair shop.
The creation of new housing types to satisfy the current housing deficit is dependent on the urban impact, the involvement of parties, and the capacity of each entity to contribute a local solution. The typology of units, the availability of services, and the relationship between private and public space is fundamental for the city to provide sustainable housing options in the long term.
Housing of the future
New housing typologies follow new family formats and a demanding economic reality. The future of housing must be created within layers of private and public space to create a supportive environment. The future of single-family homes is transforming from less single-family and more collaborative between neighbors. The home of the future is efficient and effective in its use of space and it welcomes residents in all stages of life. It sets the stage for individuals with different physical and cognitive abilities to engage in civic participation.
The future of housing is heterogeneous and a promoter of safe and affordable options. It includes more villages and additional dwelling units that foster collaboration and social support. With shared amenities and outdoor features, future units are beneficial for families of different economic and cultural backgrounds.
Communal use of outdoor spaces, shared parking, and proximity to transit provide privacy while contributing layers of semi-spaces. The future of housing promotes independent living, self-agency, and is accessible to public services.
The pandemic of 2020 reframed housing as shelter and emphasized a flexible approach to use of space – private and public. Home is, and will always be, the most significant space for individuals of belonging and safety. Innovative typologies are the most relevant measure in the future exploration of housing options to compensate for the current dehumanizing deficit.
The public realm, and how the private space reconnects to its surroundings, is the organizer of every other social dynamic. From education to access to healthcare, affordable housing results from a contributing relationship between all tangible and intangible factors of the built environment.
The future of housing must balance the effects of data that can anticipate social and cultural needs for space. From policy makers to architects, professionals and homeowners that influence the built environment have the capacity to contribute to affordable and sustainable housing.
The future of housing is today.