By Stephen Schreiber

Almost three decades ago, I wrote the following article for Designer Builder, a Santa Fe, NM, magazine. The issues in this piece remain largely relevant today. In 2021, when I was on the Town Council, Amherst approved changes to its zoning bylaw to increase the maximum square footage of accessory dwelling units (ADUs), to create a more streamlined permitting pathway for ADUs, and to add additional design guidelines. These changes more or less rendered single-family zoning obsolete in Amherst, because ADUs are allowed by right in all residential districts.

Is Single Family Zoning Obsolete?

(Stephen Schreiber, Designer Builder, November 1995)

Among the most enduring images of the United States are the enormous tracts of suburban single-family detached houses that blanket almost every urban edge. These ubiquitous developments, outside of traditional city centers, have proven to be among the most socially, economically, and environmentally destructive land use patterns ever invented.

Yet, zoning codes, subdivision laws, banking policies, and developer habits continue to encourage suburban growth. Furthermore, until recently, planners and architects have been ineffective at presenting alternatives to sprawl. The problem is particularly severe in suburban communities, which grew primarily as automobile cities. The low density of post-World War II neighborhoods makes many such communities “suburbs in search of a city.”

A related issue in low-density towns and cities is housing affordability. The single-family dwelling is by far the most common housing type in many communities. But the typical residence has been priced out of many potential buyers’ ranges, primarily because of land costs and available house types. Furthermore, these suburban communities generally force a typical family to own and use at least two cars.

One of the hallmarks of American suburbs is the zoning laws that allow only one family to occupy a dwelling on a particular site. These codes also typically forbid roommates (over a certain number), separate living quarters, and home offices. Furthermore, the regulations control setbacks, lot sizes, and many other issues. 

A  report on “Housing and Affordability,” edited by Doug Kelbaugh, notes that the ubiquitous zoning laws, which permit only single-family detached houses, have stymied efforts in many urban areas to make city neighborhoods denser, more efficient, and more sustainable. Kelbaugh argues that states should pass ordinances which allow every owner of a detached  house to establish a rental apartment in that home or attached to its garage. He concludes that, “This is probably the single most cost effective way to quickly and broadly provide affordable housing units.”

These types of accessory living quarters have flourished for years. Many of these structures were built before they were banned by zoning codes, while many were made legal only through a laborious zoning permitting  process. Others, of course, were constructed without permits.

The supply of affordable rental housing would greatly increase, particularly in desirable areas (near employment centers). Home owning would become accessible to many more people because of the additional income from the rental units. Existing neighborhoods could accommodate a more diverse matrix of household types, social groups, and incomes.

Extended families could stay together more easily. By densifying, the city could substantially grow with almost no expansion of urban infrastructure and city services. In fact, it would make some services (such as public buses, sewers, and fire stations) much more efficient.

James Kunstler argues in his book, Geography of Nowhere, that American cities lost a significant richness to civic life when governments began to ban auxiliary apartments. This ban led to significant economic segregation and contributed to sprawl. By allowing ADUs, cities can take major steps in improving housing affordability and arresting sprawl.

Stephen Schreiber is an architect and chair of the Department of Architecture at UMass Amherst. He was an elected Town Councilor in Amherst from 2018-2022.