Zoning Innovation from Coast to Coast

Federal, state and local regulations to crack the code for housing and equity.

Suddenly, it seems like everyone is talking about zoning. Yes, that zoning — the esoteric focus of interminable planning commission meetings and doorstop code books. Across the country, the critiques and calls for reform of conventional approaches to regulating development have moved from government meeting rooms to mainstream and social media.

New apartment building complex in residential area

Courtesy of Sightline Institute; photo by Flaherty & Collins Properties.

Communities have zeroed in on zoning reform as a key to boosting the supply of housing.

In cities as far-flung as Greenville, S.C., and Spokane, Wash., communities have zeroed in on zoning reform as a key to boosting the supply of housing in the face of rapid population growth. Louisville, Ky., is looking to increase housing choices while addressing a legacy of exclusionary practices against Black residents. States from California to Montana to Massachusetts are wading into the local regulatory fray with motivations ranging from addressing homelessness to adapting to climate change.

“Right now, zoning is in the national consciousness,” said Toccarra Nicole Thomas, executive director of the Form-Based Codes Institute at Smart Growth America. She noted that nearly every state in the union has a severe shortage of homes, with the national shortfall nearing a record 4 million units. “It is clearly at the root of the housing crisis, and it’s getting attention for that. Before 2020 you would say ‘zoning’ and their eyes would glaze over. Now, everyone knows it’s critical.”

New home with blue siding showing a car parked in the driveway

Courtesy of Sightline Institute

“In terms of the housing crisis, zoning out apartments is a huge culprit,” said Yonah Freemark, research director, Land Use Lab at Urban Institute. Across the country, the nation’s more than 30,000 local governments have outlawed more than one home per lot on the vast majority of land available for housing, and often impose onerous restrictions on land that is available for multiple units, he noted. “NIMBYs have been around forever, but in the past four years the concept of YIMBYs has risen,” or Yes In My Back Yard, said Freemark’s colleague, Lydia Lo, research associate with the Metropolitan Housing and Communities Policy Center at Urban Institute. Organizing through social media and local meetups, housing advocates have begun pushing for zoning overhauls in localities and states nationwide, with growing success.

States Act to Limit Local Restrictions on Housing

Over the last few legislative sessions, a wave of states considered or adopted reforms that require localities to plan and zone for more housing. In 2023 alone, legislatures in Washington, Montana, Rhode Island, Colorado and Arizona considered bills to allow, by right, additional residences on the same property as stand-alone houses, also known as accessory dwelling units, or ADUs. Ultimately Montana and Washington voted to join California, Oregon and Maine, who made similar moves in recent years. Legislatures also considered measures to legalize so-called middle housing in single-family zones. Those are the smaller multi-unit buildings — such as duplexes, triplexes, quadruplexes, townhouses, courtyard apartments — that were common in popular neighborhoods from the early 20th century before being outlawed by mid-century zoning changes. Also, this year, California, Oregon and Montana strengthened ADU rules by barring localities from imposing mandatory parking requirements on new accessory units.

Washington state drew particular attention this year. In a session billed as “the year of housing,” and with Governor Jay Inslee as a prominent cheerleader, legislators considered a raft of bills aimed at opening vastly more territory to a variety of housing types, especially in proximity to high-capacity transit. While bills to eliminate restrictions on apartments near rail and rapid-bus stations were left to another year, the legislature did adopt sweeping bills to legalize middle housing and ADUs across the state. “On the vast majority of residential lots all across Washington, cities will no longer be able to restrict choice to a single-detached house,” says Dan Bertolet, director of housing and urbanism at the Seattle-based Sightline Institute. Writing in the immediate aftermath of the session, he noted: “The most pervasive and harmful form of exclusionary zoning is a thing of the past.”

In cities with populations of 75,000 or more, House Bill 1110 legalizes four homes per residential lot, and six per lot within a quarter mile of a major transit stop, or anywhere if two of the homes are affordable to lower-income residents. In smaller cities, two to three units will be allowed. Cities must adopt zoning that complies with the bill within six months of completing their next comprehensive plan update in accord with state deadlines. Washington’s middle housing law goes a step farther than Oregon’s ground-breaking 2019 measure, which legalized four homes per lot in Portland metro-area cities over 25,000 and two per lot in smaller cities statewide. The Seattle-area metropolitan planning agency estimated that HB 1110 will yield an additional 75,000 to 150,000 homes over the next 20 to 30 years in the Puget Sound region.

Middle housing and ADU changes alone will still leave a formidable gap in available and affordable housing.

But the middle housing and ADU changes alone will still leave a formidable gap in available and affordable housing in proximity to the Puget Sound region’s burgeoning job centers, Freemark said. The region has been growing at a rate of 1,000 new residents every week and another 1.6 million people are expected to call the region home by 2050. He noted that the region is investing over $50 billion to develop a light rail network of 116 miles and 80-plus stations and bus-rapid transit connecting 30 cities. Making the most of that investment and ensuring that residents of all incomes have access to homes and jobs, will require thousands of units of new housing within a half-mile of transit stations. “The Puget Sound region is investing more in transit than any other region at the moment, but local jurisdictions could undermine it,” said Freemark, who worked with colleagues at the Urban Institute to create a report on the housing potential of the transit network. “Some communities have gone out of their way to limit apartments, despite gaining the advantages of new rail and bus rapid transit lines.” While a pair of bills that would have overridden local bans to legalize apartments in proximity to transit stations failed this year, Freemark expects there will be continued pressure for state and regional action to ensure attainable housing along light rail and bus lines.

In California, a Toothless Tiger Bites: The Housing Affordability Act

Struggles over local limitations on housing construction have plagued California for years. In the 1980s, the state adopted a Regional Housing Needs Allocation that attempts to assign a target for new housing to each jurisdiction according to expected growth. Every eight years, jurisdictions must update the “housing element” of their plans to show how they will comply. To add teeth to that requirement after it was ignored for several years, the state passed a Housing Accountability Act that provided for a “builder’s remedy” when municipalities fail to zone to meet the housing target: The jurisdiction’s zoning is suspended and proposed projects that include at least 20 percent affordable units may proceed, with or without local approval. Intended more as a threat than a promise of action, the builder’s remedy was rarely invoked. But recently, the state has run out of patience as the housing crisis has become overwhelming, even as it ratcheted up the number of affordable units expected from communities.

Last fall, Santa Monica became the cautionary tale. After missing a deadline to comply in the face of multiple warnings, the state revoked the city’s control over height and density for residential projects meeting goals for moderately priced and affordable housing, pending compliance. During the window that followed, developers proposed 16 projects with 4,562 units up to 15 stories tall that met the criteria for approval under the builder’s remedy. Having gotten the city’s attention, the developers later negotiated down to 10 projects of more modest proportions. State officials, land-use attorneys and local officials continue to debate the legality and practicality of the builder’s remedy, but meanwhile dozens of jurisdictions have raced to submit compliant plans.

From Conventional Zoning to a “Form-Based” Approach

While more states are getting into the act to loosen local restrictions on housing, the truth is that in most places municipal governments continue to hold nearly all the cards in regulating land use and development. And many are themselves realizing that tight restrictions on housing supply are leading to soaring rents and home prices, while displacing all but the highest-earning workers to far-flung locales. As they look to provide more options for middle housing in walkable, less car-dependent neighborhoods, some are recognizing the limitations of conventional zoning, which typically isolates housing types from each other and from daily needs such as shopping, schools and work and connects them by car trips. In addition, most zoning regimes add a layer of discretionary review that tends to make development more expensive and the outcome less predictable.

The best codes are created with a lot of resident input about how the finished product should look and feel.

Over the last 20 years, about 400 such jurisdictions have turned to form-based codes, according to Thomas of the Form-Based Codes Institute. Rather than establish single-focus zones where most land uses are excluded and densities tend to be low, form-based codes work to foster neighborhoods of varying types that can have a mix of uses. The best codes, Thomas said, are created with a lot of resident input about how the finished product should look and feel. Development proposals that meet those criteria can proceed without discretionary code or design review.

Form-based codes work to foster neighborhoods of varying types that can have a mix of uses.

These days, Thomas is fielding a rising number of queries about how form-based codes can replace or augment conventional zoning. Some are exploring whether to use the codes as an overlay for districts that are destined for density, in cities such as Buffalo, N.Y.; Arlington, Va.; Birmingham, Ala.; or as an option that neighbors and/or developers may choose, as in Cincinnati, Ohio. Other cities are looking into form-based codes as part of a wholesale overhaul of their approach to shaping development, as Miami, Fla., and Beaufort, S.C., have done. While she expects an upsurge in use of form-based codes amid today’s intense zoning debates, she doesn’t foresee anything like the original promulgation of “Euclidian” zoning, so named for the 1926 Supreme Court case that declared regulatory segregation of uses to be legal.

“Two years after that decision, 19,000 communities had adopted zoning,” she said. “There was a federal push, multiple agencies championed it. It was almost like you couldn’t escape it. Form-based codes have taken an opposite tack, working their way up from the bottom, when communities go looking for an alternative that promotes a better mix of uses, encourages gentle density to create more walkable neighborhoods. Do you want a people-oriented community or car-oriented community? It gives you the streetscape and the building form. You can build at a human scale that is appealing to people.

If you want Main Street Americana, you’re not going to get it with Euclidian zoning.

“The conventional zoning of separated uses surrounded by parking does not do that. If you want Main Street Americana, you’re not going to get it with Euclidian zoning.”

Louisville Confronts a Legacy of Racial Exclusion in Dealing With Zoning Reform

Metro Louisville, Ky., was an early adopter of form-based codes. Since 2003, the city has employed a two-tiered system, as their website explains: “Traditional ‘use zones’ govern permitted uses while 11 overlying ‘Form Districts’ govern urban form and dimensional standards of structures.”

Louisville, KY community meeting involving a diverse population on zoning reform

Courtesy of City of Louisville, Ky.

“People liked the way things looked with form-based codes, but weren’t ready to do away with conventional zoning,” said Joe Haberman, planning manager for the Louisville Metro government. As a result, city codes have continued to perpetuate a legacy of racial segregation that in 2021 became the subject of intense municipal soul-searching.

Noting that most Black residents continued to be concentrated in areas west of downtown, while earning less and paying a larger share of income for housing than their white counterparts, the city partnered with the Urban Institute to highlight the reasons why, as a precursor to action. The city created a website with a “story map” detailing the racist origins of zoning, beginning with a 1914 segregation ordinance prohibiting Black families from living on blocks with a white majority, and vice versa. That ordinance would become the flashpoint for a landmark 1917 Supreme Court decision, Buchanan v. Warley, in which the court declared it a violation of the 14th Amendment to prevent owners from selling to a particular race. But because it focused on property rights without addressing the goal of racial exclusion, the decision opened the door for myriad regulatory workarounds that had the effect of segregation without overt reference to race.

Like many other cities, Louisville in 1929 hired Harland Bartholomew to write what would become the 1931 Comprehensive Plan. His plan recommended using eminent domain to acquire and clear the “slums” where Black families lived, and to use zoning to prevent incursion of Black families into areas reserved for white residents.

Future iterations of the city’s planning and zoning documents avoided outright reference to race but used coded language — and land use codes — to achieve the same ends. The 1958 Plan, for example, called for “deed restrictions, larger single-family lots, and private open space to create exclusionary single-family neighborhoods,” the story map notes. The 1970 comprehensive plan used the needs of the automobile as an additional exclusionary tool, promoting car-only development and leaving out public transit and sidewalks.

“The main thing we tried to do was first be honest with ourselves and look at past practices and acknowledge their legacy,” Haberman said. “Sometimes looking at negative things your profession did makes you uncomfortable, but it helps when you have the support of local elected officials.”

To undo the lingering harms, city officials began engaging with the community to explore ways to prevent displacement of Black families as downtown-adjacent neighborhoods become more sought-after by developers and to encourage more attainable housing in areas where Blacks had previously been excluded. “We made a concerted effort to talk with as many people as we could. Historically Black communities in West Louisville felt they were neglected by government and didn’t participate in traditional outreach efforts, where people had to come downtown,” Haberman said. “Instead, we had sessions in community hubs and got more engagement than we ever had. We held meetings at multiple times of day, had open houses, and tried to be as flexible as possible. We also tried to be creative in how we presented information and had people available to talk to people one on one. Now we have much more diversity by geography, race and age participating than we ever have before.”

Like many jurisdictions, Louisville started by successfully proposing to ease restrictions on ADUs, allowing them on most lots and reducing parking requirements in urban zones. Planners are now working to update land-use maps to allow more middle housing in various parts of the consolidated city-county. “We have comp plan policies that support a mix of housing styles and choices throughout,” Haberman said. “Our goal with middle housing is to make sure we have options throughout the county and aren’t limited to certain parts of it.”

The politics of the changes can be difficult, he acknowledged. “Most of our zoning does not allow multifamily. For anything different, we really have to get out in the community and explain how more density in certain places can be a good thing.” As of late summer, planners were six months or more from proposing new middle housing rules. “In general, we’re offering it as choice, not as a requirement. You can do multifamily in more places if it’s designed properly for that place.” Those design considerations could point to greater reliance on form-based codes in the future, and a potential shifting away from use-based zoning, he said.

Spokane Opts for Quick Action with Pilot Programs Suspending Single-Family Zoning Restrictions

As previously reported in On Common Ground, in 2021, The Spokane Association of REALTORS® (SAR) and collaborative partners, enlisted the Counselors of Real Estate’s CRE® Consulting Corps to undertake a housing survey. The Counselors’ resulting report, “Action Steps to Increase Spokane’s Housing Supply,” included data illustrating Spokane’s current housing situation, recommendations on how to address the crisis such as density and zoning changes, and examples of best practices from around the country to serve as a guide. “Everybody the CRE team spoke to recognized the housing situation as a crisis,” said Darin Watkins, government affairs director for SAR. “There are going to be multiple approaches and many solutions to the challenges we’re facing, and in the year since our efforts began, the report has already helped change the narrative in a positive direction.”

A multifamily home under construction under the BOCA (Building Opportunity and Choices for All) interim ordinance in Spokane.

Courtesy of the City of Spokane.

Watkins, said they also met with the city’s planning director, which is essential because the director acts as the public interface, the gatekeeper for developers, coordinator with the city council and manager and influencer throughout the process. It is important for REALTORS® to become involved in the process, as “they have the data and information and can be the driver for change,” Watkins emphasized.

In response to the crisis, city planners in 2022 developed the Building Opportunities and Choices for All initiative, or BOCA, a one-year, emergency pilot program that suspended single-family zoning restrictions citywide and made it legal to build duplexes, fourplexes and townhomes in any residential area. The idea was to have a real-world look at what the changes might produce, both in terms of housing product and effects on neighborhoods. Rather than engage in a lengthy and potentially contentious public process at the outset, the city would conduct an experiment then conduct outreach based on what was observed. “There have always been voices calling into question the ways we regulate housing,” said Spokane planning director Spencer Gardner. “You can go back to the 60s and 70s and find people criticizing exclusive single-family detached zoning. It’s not a new topic. But the housing crisis has really elevated it.”

The experiment appeared to produce results. In the first five months of 2023, the city issued 509 multifamily and mixed-use housing permits, more than any other time period on record. In the mix were a couple dozen duplexes and half-dozen fourplexes, housing types that in recent decades were few and far between. Not only that, but Spokane’s program gave juice to what become House Bill 1110, the law that legalizes fourplexes statewide.

It’s a back-to-the-future moment in Gardner’s view. He noted that Spokane in 1900 to 1910 tripled in size to 70,000 residents. “That’s monstrous growth. But it’s also the period when we built these beautiful neighborhoods that people love. Part of the solution to our housing crisis is looking to what our ancestors did for their housing crisis.

“The classic example is the Cliff/Cannon neighborhood on the south side of downtown. When you walk around, you find that housing built in late 19th and early 20th centuries is housing that is mixed in terms of size and types. It provides a lot of the type of neighborhood feel that our comp plan says we should encourage. And, over the last year, new development has been occurring on vacant or underused properties within the city. These are infill lots that have sat undeveloped for decades. They are coming back into play as a result of market forces and the code change,” he added.

Gardner’s office is working to develop the permanent code changes, which he expects to happen in November, and to look very similar to the pilot program. Meanwhile, the mayor and council have launched additional pilots. In February 2023, the council passed an ordinance dubbed “Pavement to People,” which offers tax breaks to incentivize developers to build affordable housing on downtown surface parking lots. And in July, the city started a one-year pilot removing the requirement that developers construct parking spots when building new apartments or houses within a half-mile of transit stops. Spokane also made it legal for a landlord to charge less for units that don’t come with parking.

Missing Housing Meets Resistance in Greenville, S.C.

Like Spokane, metro Greenville, S.C., is a formerly sleepy area that has become a sought-after refuge of lower home prices and high quality of life, a success story high-profile enough to earn a 60 Minutes segment last year. The city of Greenville has seen its population surge by 20 percent over the last decade, with the pace growing in recent years. In an effort to shape that growth while promoting more housing construction, the city in June adopted a new development code and zoning map that identifies 11 “nodes” with mixed housing types and walkable densities, as well as four “corridors” along thoroughfares linking the nodes. Missing from the new code, though, is a provision to allow missing middle housing in more single-family zones, said Chris Bailey, CEO of Greater Greenville Association of REALTORS®.

Greenville, SC community meeting on zoning

Courtesy of Greenville, S.C.

Beginning in 2019 Bailey and other REALTORS® had partnered with Upstate Forever, a smart growth and conservation advocacy group, to launch a public discourse about missing middle housing, its role in shaping traditional Greenville and potential to offer more housing choices to more people. The partners worked to bring the firm Opticos Design in to conduct a scan of existing middle housing that could be used as a guide for introducing it more places through code changes.

“When we first explored this topic with a coalition, it was at a time when people in this part of the world weren’t talking about missing middle,” Bailey said. “It was pre-COVID, housing affordability wasn’t such an issue. The timing was good because Greenville city and county were required to update their 10-year comp plan.”

After a year and a half of stakeholder meetings and several drafts of the plan, “missing middle ended up being a part of the proposed policy documents,” Bailey added. “That missing middle housing product showed our planners how to do density without it looking like density. It’s not an alien concept, you already have it in your community, and it’s not high density that will swallow up your neighborhood.”

Any time you can increase housing choice you are meeting key parts of the market. For first-time buyers it can be perfect. But even rental helps, because the more housing choices you have, the more it drives-down costs and gives people a chance to move up.”

Implementation has proved to be a challenge, he said. “The planners are identifying places in the city where density makes sense, but then in response to neighborhood pushback you see them decreasing density. There is a lot of NIMBY-driven stepping back. As much as I would like to write a feel-good success story, we have realized that this is a long-term game. The good thing is that we have put ourselves at the table for so many policy discussions.”

State and Regional Action to Stem the Housing Crisis

Greenville’s situation is more the norm than an outlier, the Urban Institute’s Lo noted. “At the local level, the cost of reform in political capital can be enormous,” she said. “But we need results-based zoning and land-use policy, wherein local governments are held accountable for meeting housing demand for all incomes and circumstances, and for reducing costs associated with housing and transportation. To ensure that all jurisdictions participate, and to be fair to the more willing participants, action needs to happen at the state or regional level. Don’t dictate the means for meeting targets, but set the expectation that the jurisdiction must find a way to meet results.”

“I’ve been on record in the past of being skeptical of state action,” Spokane’s Gardner said. “There are times when state imposing top-down solutions can lead to suboptimal outcomes. With the housing issue, my thinking has changed a little. There is a collective action problem. When you have a crisis like this, no locality can gain by trying to address this on their own. If you’re the only one to open up to more housing, you might get the radical change people fear. The way to get around that is for all to go at once, and that’s where state action helps. As the crisis has worn on, it has become more and more apparent that state action was necessary.”


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