The Granny Flat Rebellion: Preempting Local ADU Restrictions

Authors

Andrew Welch, Southern Methodist University, Dedman School of LawFollow

Abstract

States around the country are increasingly facing the challenge of housing shortage and uncooperative localities attempting to keep developers out of their neighborhoods. The “Not in My Backyard” (NIMBY) groups are not representative of the American desire to create affordable housing, and allowing neighborhoods to dictate national and state policy is ineffective. Accessory dwelling units (ADUs)—small, self-contained residential units on single-family-zoned property—are a cost-effective strategy to expand housing options, promote intergenerational living, and foster economic mobility. This Comment addresses how states can chisel away at the housing crisis and how ADUs may alleviate many of the problems if they are not prohibited by local governments.

To alleviate the problem of unaffordable housing, many states and cities have begun to adopt more permissive zoning ordinances, which can be some of the greatest obstacles to the development of affordable housing in cities. Among these affordable housing strategies is permitting ADUs by right. Proponents of these affordable housing laws claim that allowing homeowners to construct an additional dwelling unit on their property will increase housing options and economic mobility. Many cities, subject to the whims of NIMBY groups, fight against these state laws alleviating the affordable housing issue by finding creative ways to deny ADU permits. Recently, several states have pushed back against city regulation by permitting ADUs by right, preempting owner-occupancy and off-street parking requirements, and sometimes even providing financial assistance to build ADUs. These preemption laws not only accelerate housing production but also prevent NIMBY-driven standstills without compromising public health, safety, or neighborhood character. This Comment argues that states should encourage affordable housing and follow the growing ADU-by-right trend by adopting laws that preempt cities from regulating the construction of ADUs and using poison pills that threaten their viability, including owner-occupancy requirements, minimum lot sizes, and minimum parking requirements.

Recommended Citation

Andrew Welch, The Granny Flat Rebellion: Preempting Local ADU Restrictions, 78 SMU L. Rev. 1239 (2025)