Princeton planning and zoning has had unintended exclusionary outcomes, making it hard for local middle-class workers to live in town, and incentivizing car-dependency and traffic. In this series, we explore options for adding more walkable housing in Princeton to enable diversity and inclusivity, while maintaining and enhancing Princeton’s historic charm.
Accessory dwelling units are self-contained units in owner-occupied single-family homes. They can be internal, such as a converted basement; external, such as a second building or converted garage; or accommodated in an addition to the building. In some cases, they are ‘in-law units’ or ‘granny flats’, where an extra dwelling unit allows family to live on the same site with increased privacy and independence. However, it is equally valid to rent them to non-family members.
In recent years, accessory dwelling units (or ADUs) have been seen as a potential solution to adding housing in communities that are considered ‘built-out’. One phenomenon of the late 20th century has been a significant decline in the average number of occupants of each home. Allowing accessory dwellings helps reverse that trend, by allowing more than one household to share an existing lot. More ADUs in Princeton would increase housing opportunities, and in most cases, these housing opportunities would be at the lower end of the market, i.e. cheaper rental properties that are in the greatest demand. There are benefits to the homeowner as well, as extra rental income can help offset high property taxes.
Incentivizing new accessory dwellings would have minimal impact on Princeton’s historic charm. Internal ADUs, such as converted basements, are almost invisible, and even external secondary housing units can be extremely tasteful and do not add significantly to the overall impervious surface of a lot (as seen in the photo above).
Princeton already has a flat ordinance which can be used by homeowners to rent out accessory dwellings. Nonetheless, more flexibility, for example in terms of setback limits and parking minimums, could incentivize more homeowners to add ADUs, thereby increasing the supply of housing to middle-class workers. Another restriction which could be eliminated is the limit of only one ‘flat’ per property. It’s not obvious why two flats would be a big problem on large lots. There is probably the potential for several hundred additional housing units in Princeton through expanding the pool of ADUs.
Please leave your comments below…do you think incentivizing ADUs is a reasonable way to increase housing opportunity in Princeton? To what extent would it impact the historic charm of the town? What are the risks? Would you consider living in a converted garage or basement in Princeton, if one was available in your price range?