Elisabeth Haub Law School of Law
Pace University
Land Use Law Center
Supervisor: John R. Nolon, Distinguished Professor
Blog No. 23 of the Land Use, Human Health, and Equity Project
Editor: Brooke Mercaldi
Contributing Author: Bailey Andree [*]

Zoning to Fill the Missing Middle Housing Gap


Previous blogs, including “Housing, a Crucial Determinant of Health,” defined and discussed the seriousness of housing insecurity, one of the four pandemics evaluated by the Land Use, Human Health, and Equity Project at the Land Use Law Center. Housing demand is outpacing housing supply and new housing needs to respond to a massive demographic shift. In contrast to the mid-late nineteenth century’s nuclear family, one in four households today is a single-person household. One in three adults has never married. The birth rate is dropping. All of these factors contribute to the increasing need for housing variety. Zoning’s emphasis on single-family housing greatly limits the production of different types of housing. Simply put, Missing Middle housing is zoned out in most places.


In response to the worsening housing crisis, there is a trend toward zoning for Missing Middle housing development. Missing Middle zoning permits the development of two-, three-, and four-family housing and smaller-scale multifamily buildings to provide the variety called for by the country’s changing demographics. It is a “range of house-scale buildings with multiple units – compatible in scale and form with detached single-family homes – located in a walkable neighborhood.” These units provide housing for young professionals, senior households, and low- to moderate-income individuals. Missing Middle units may include duplexes, triplexes, townhomes, tiny homes, small apartment buildings, and more. The typical Missing Middle development has 4-8 units per lot or building.


The effects of the housing crisis are widespread. The United States Census Bureau estimates 29.8% of the over 122 million households in the U.S. are cost burdened, spending 30% or more of their monthly income on housing. Equaling over 36 million households, this is a problem a large portion of Americans face. While this is felt by all, the burden weighs heavier on minority groups. The National Low Income Housing Coalition estimates that “30% of Native Americans, 35% of African Americans, and 28% of Hispanic households have extremely low incomes” compared with 22% of white non-Hispanic households. These disproportionate impacts of the housing pandemic paint a clear picture of the crisis we face. Missing Middle housing addresses these impacts on minority communities while also combating economic disparities between traditional single- and multi-family zones.


One method of creating Missing Middle housing is to amend current zoning codes to allow mixed-use or Planned Unit Development (PUD) while maintaining single-family zones. Both Auburn, Maine and North Brunswick, New Jersey have recently amended their zoning codes to allow for PUD to encourage creation of a diverse housing stock, including duplex, townhouse, and garden apartment housing. PUDs are overlay districts that often allow mixed-use in an otherwise single-use zone, including residential and commercial units permitted as of right. Montpelier, Vermont amended its zoning code to create a mixed-use residential district to promote infill while maintaining community character. This technique will allow for much of the zoning code, and therefore community, to remain the same while certain aspects are changed to promote Missing Middle development.


Another zoning method to alleviate the pressures of the housing crisis is to eliminate single-family zones altogether. In Berkeley, California the zoning code was amended to eliminate all single-family zones and replace them with multi-family zones, allowing for development of duplexes, triplexes, and fourplexes to alleviate the city’s housing strain. Similarly, Accessory Dwelling Units and duplexes are permitted as of right in all residential zones in Olympia, Washington while cottage houses, triplexes, fourplexes, and townhouses are permitted as of right in most residential zones. Both of these jurisdictions have successfully updated their zoning codes and exemplify the steps municipalities can take to address the affordable housing pandemic.


For additional resources, the Gaining Ground Information Database is free and features best practice models used by governments to control the use of land in the public interest. Please direct your search toward the Healthy Communities topic.

[*] Bailey Andree is a second-year student at the Elisabeth Haub School of Law, Student Associate at the Land Use Law Center, and Research Assistant to Professor Nolon.

Brooke Mercaldi is a second-year student at the Elisabeth Haub School of Law and Research Assistant to Professor Nolon.

The previous blogs in the series are listed here:

  1. Reframing Sustainability: Introducing the Land Use, Human Health, and Equity Project
  2. Planning for Public Health: A New Beginning for Land Use Law
  3. The Role of Density in Combatting Climate Change and COVID-19
  4. Novel Coronavirus Claims Implicate Age-Old Property Rights Questions
  5. State & Local COVID-related Emergency Powers: Individual Rights
  6. COVID-Related Land Use Regulations and Judicial Deference
  7. Mediation of Eviction Disputes May Hold the Key to the Survival of Small Businesses
  8. Using Zoning to Help Eliminate Food Deserts: A Few Steps Forward
  9. Urban Heat Islands and Equity
  10. Urban Heat Island and Equity: What Can Local Governments Do?
  11. The Recovery Lease: Preventing Evictions of Commercial Tenants During the Pandemic
  12. The Role of Hazard Mitigation Planning in Promoting Public Health and Resilience
  13. Hazard Mitigation Planning: A Case Study
  14. Complete Streets: Protecting Public Health
  15. Zoning and Lease Mediation as a Way to Retain Critical Small Businesses
  16. Segregation by Law and the Racial Inequity Pandemic
  17. Combating Food Swamps to Improve Equity and Public Health
  18. The Pandemic Plan for Healthy Buildings
  19. Remediating Distressed Properties to Improve Public Health
  20. Housing, a Crucial Determinant of Health
  21. ADU Introduction
  22. NIMBY Restrictions to Poison the Prospects of Accessory Dwelling Units to Address Housing Insecurity


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