Hidden Density: A Proposal for Single-Family Infill Housing

Abstract

In the recent past, there has been a shift in user preferences toward walkable, urban neighborhoods. The highest housing prices are now found in dense metropolitan areas rather than wealthy suburbs and this trend is expected to continue with the growth of Generation Y and the return of Baby Boomers to urban areas. According to the 2010 Census, over 80 percent of Americans now live in urban areas. Furthermore, awareness around sustainability has become an issue at the forefront of city planning and the built environment. Methods for reducing our carbon footprint and creating healthier, more livable spaces are gaining political traction. These changes have become integral in the way we design buildings, as well as how users occupy their spaces. Despite this, many people still prefer detached housing units but find that it is becoming less realistic in urban environments in which density is now valued. Methods for retaining the single-family character of neighborhoods are now being developed in several western cities (Vancouver, Seattle, Portland, Austin). Each has implemented accessory dwelling unit (ADU) programs that allow homeowners to construct compact attached or detached backyard homes. The benefits of these programs are clear: more affordable units, increased population density to achieve more economical transit and more walkable neighborhoods. However, implementation has proven difficult for a variety of reasons. Perhaps foremost among them is that most individual families do not have the means to build or oversee a project of this complexity. In order to address the growing need for affordable rental units, changing demographics and a space market heavily stocked with single-family homes, the City of Seattle needs to reassess the core principles of its ADU program and focus on developing strategies and methods to encourage this type of hidden density.