What if Single-family Homes House Multiple Household?

At the recent APAColorado state chapter conference in Telluride, Clarion Director Don Elliott, FAICP, recently convened a panel discussion on “What if Single-family Homes House Multiple Households”. Don’s co-panelists included Denver, Colorado, Zoning Administrator Tina Axelrad, AICP, and Lakewood Planning Director Travis Parker. Panelists agreed that the extreme pressures for affordable housing in high growth communities (like the Denver metro area) are leading to many innovations in the way we design, build, and occupy housing. The growing popularity of Accessory Dwelling Units (ADUs), micro-units, tri-plexes, four-plexes, and other forms of “missing middle” housing are all outcomes of the rising (and probably continuing) pressure to resolve the gap between rising housing prices and more-or-less stagnant wages. Located on Denver’s western edge, the Lakewood, Colorado, has responded by allowing ADUs, by allowing the construction of Tiny Houses in mixed use zone districts, and by beginning a discussion about licensing short-term rentals of single-family homes. Denver has witnessed the increased pressures for affordable housing in the form of illegal second dwelling units added into existing single-family structures, illegal use of garages and warehouses for living space, illegal “group living” by more than the number of permitted unrelated persons in single-family dwelling, and increasing requests for zoning exceptions and variances related to occupancy. Although the city legalized short-term rentals in 2016, instances of illegal short-term rentals are still occurring while Denver’s enforcement capacities are implemented. The panel also discussed housing market data collected by Prof. Arthur C. Nelson at the University of Arizona showing a likely serious over-supply of structures constructed as single-family houses in non-prime locations. These structures will probably come under increasing pressure to be occupied by multiple households in order to combine the incomes required to make necessary mortgage or rental payments. While wealthier neighborhoods may be able to prevent multiple-occupancy through covenants, many less affluent neighborhoods will lack the resources or will to do so. Finally, the panel discussed a recent study by Portland, Oregon, documenting the relatively low cost of converting some single-family homes into duplexes and in some cases tri—– which often do not need to comply with stricter multi-family building codes. Potential responses to affordability pressures will include (1) allowing some portion of the single-family housing stock to be occupied by second households, (2) allowing some single-family homes to be modified into duplexes and tri-plexes, and (3) revising definitions of “family” and “household” to allow larger numbers of unrelated persons to occupy a single-family dwelling.