How have other U.S. cities updated separation ordinances since 2024 and what outcomes followed?
Executive summary
Since 2024 a patchwork of city-level changes—mostly easing density limits, enabling accessory dwelling units (ADUs), and implementing inclusionary zoning (IZ) or preference policies—have reshaped local separation-era ordinances, often because states passed new mandates or model ordinances that cities then had to adopt or adapt [1] [2] [3]. Outcomes reported in the literature and trackers include more permissive rules for ADUs and some IZ-driven affordable units reaching lower-poverty neighborhoods, while countervailing forces—state preemption, limited planning capacity, and entrenched exclusionary incentives—have constrained how much local ordinance changes reduce segregation [3] [4] [5] [1].
1. What cities changed and how: ADUs, density, and inclusionary tweaks
A dominant trend documented by municipal trackers and policy briefs is municipal ordinances that relax single‑family exclusivity and explicitly allow more ADUs and multifamily housing in formerly restrictive zones—changes taken either to comply with new state laws or to follow state model ordinances that emerged in 2024 (Othering & Belonging’s Zoning Reform Tracker; [3]; [9]0). States such as Maryland and several New England legislatures wrote laws in 2024 requiring cities to allow higher density near transit or on government land, prompting local ordinance updates to permit duplexes, triplexes, and more ADUs [1] [2]. Where cities pursued IZ, some altered local ordinances to require or incentivize affordable units as part of new developments [4].
2. Outcomes: housing supply, distribution, and limited integration gains
Evaluations cited in municipal reform reporting show measurable but uneven outcomes: ADU reforms have generated more permitted units in cities that implemented streamlined rules, and IZ programs in some places produced affordable units that were sited in lower‑poverty neighborhoods—evidence RAND summarized across 11 cities—suggesting potential for economic integration [4]. State- and city-level reporting indicates that technical assistance and data reporting requirements introduced in 2024 helped some jurisdictions process new housing types more quickly, increasing permits where capacity existed [1]. However, the Othering & Belonging tracker notes that the predominant reform mechanism remains municipal ordinances and that results are uneven, with ADU reforms concentrated in places already likely to see investment [3].
3. What didn’t change: structural limits and legacy separation
Scholars caution that changing an ordinance is necessary but not sufficient to erase the structural roots of residential separation: historical zoning and land‑use regimes created over decades—single‑family minimums, lot-size rules, and exclusionary infrastructure—continue to shape outcomes even after ordinance amendments [6] [7]. The academic literature emphasizes that many reforms must confront these embedded mechanisms if integration is to be durable [6].
4. Political and legal frictions: preemption and local capacity
A persistent constraint is state preemption and partisan mismatch between city and state governments; Ballotpedia and NLC analyses document frequent instances where state law or court decisions have overridden municipal ordinances or limited local policy levers—meaning some cities that sought to relax separation-era rules were blocked or circumscribed by higher authorities [5] [8]. The Minneapolis Fed analysis further highlights that states often accompany legal changes with model ordinances and technical assistance because many smaller cities lack the planning capacity to rewrite complex land‑use codes on their own [1].
5. Debates, agendas, and the road ahead
Reform advocates frame ordinance changes as corrective—undoing anti‑density rules that hoard resources and exacerbate race- and class-based exclusion—while opponents often invoke neighborhood character and property‑value concerns; codified reforms therefore sit at the intersection of planning technocracy and political economy, benefiting those able to mobilize legal and financial resources to build [3] [6]. The trackers and policy reports make clear that where reforms are paired with funding, reporting, and anti-displacement measures (for example preference policies tied to IZ), outcomes for displaced residents can be positive, but evidence is still limited and localized [4].
Exact impacts remain contingent on how cities implement ordinance language, whether state preemption intervenes, and whether complementary investments and monitoring follow—sources report successes in unit approvals and targeted placements but stop short of claiming broad reversal of historical segregation without sustained, coordinated policy beyond single ordinance changes [3] [4] [1] [2].