Accessory dwelling units (ADUs) have experienced a recent resurgence due to rising costs of housing and state and local efforts to relax regulations and adopt other measures to support ADU development. This review focuses on scholarly, professional, and gray literature on actions and tools to support ADUs that a) go beyond reform of land use regulations, and b) specifically address affordability concerns. We seek to provide an updated and accessible distillation of key issues related to financing, affordable ADU rental and ownership strategies, legalization, and assembling an ecosystem of networked public and private sector roles in ADU development and management.
AARP. 2020-21. Accessory Dwelling Units: Model State act and Local Ordinance. Washington, DC: Author.
4.
AARP. 2023. Expanding ADU Development and Occupancy: Solutions for Removing Local Barriers to ADU Construction. Washington, DC: AARP and American Planning Association.
AnackerKatrin BNiedtChris. 2023. “Classifying Regulatory Approaches of Jurisdictions for Accessory Dwelling Units: The Case of Long Island.” Journal of Planning Education and Research43 (1): 60–80. https://doi.org/10.1177/0739456X19856068
7.
AntoninettiMaurizio.2008. “The Difficult History of Ancillary Units: The Obstacles and Potential Opportunities to Increase the Heterogeneity of Neighborhoods and the Flexibility of Households in the United States.” Journal of Housing For the Elderly22 (4): 348–75. https://doi.org/10.1080/02763890802458320
8.
ArmentaDoraCarlsonCateDryjanskiThomsonFigelAnnaGardeaZachariasHagarJonathanHollandTaylor, Stephanie, et al.2019. A Community of Casitas: Fighting Displacement in Pacoima with ADUs and CLTs. Los Angeles: University of California, Department of Urban and Regional Planning.
9.
BennettAlysaCuffDanaWendelGus. 2019. “Backyard Housing Boom: New Markets for Affordable Housing and the Role of Digital Technology.” Technology Architecture+ Design3 (1): 76–88. https://doi.org/10.1080/24751448.2019.1571831
10.
BenzieAlexCacciolaCristinaChuDevinBarcellosNatalieGrantRichardNiehausSkylarNsairSuemiya. 2020. Alternatives to Long Term Care and Housing: An Environmental Scan. Waterloo, Ontario, Canada: University of Waterloo, Plan720 final report.
BrownAnneMukhijaVinitShoupDonald. 2020. “Converting Garages into Housing.” Journal of Planning Education and Research40 (1): 56–68. https://doi.org/10.1177/0739456X17741965
15.
BrownMarilyn AHubbsJeffreyVincentXinyi GuChaMin-Kyeong. 2021. “Rooftop Solar for all: Closing the gap Between the Technically Possible and the Achievable.” Energy Research & Social Science80: 102203. https://doi.org/10.1016/j.erss.2021.102203
CastlemanTerry.2024 (Aug. 7). L.A. County is epicenter of new backyard ADUs; Lower- and middle-income cities lead the building boom. Los Angeles Times, A.1.
ChappleKarenWegmannJakeMashhoodFarzadColemanRebecca. 2017. Jumpstarting the market for accessory dwelling units. Terner Center for Housing Innovation.ternercenter.berkeley.edu/more-ADUs.
EarlHayden Baird. 2023. ““The Availability of Affordable Housing” Crisis: Tiny Homes and Urban Infill.” THE Real Property, Trust, and Estate Law Journal58 (2): 105–36.
HardmanAnna. 1996. “Informal Additions to the U.S. Housing Stock.” In Under one Roof: Issues and Innovations in Shared Housing, edited by HemmensGeorge CHochCharles JCarpJana, 33–48. Albany, NY: State University of New York Press.
49.
HofflerChristopher J.2023. “Tiny Home Lot Split Policy: A Needed Adjunct to Accessory Dwelling Units in Promoting Affordable Housing.” North Carolina Banking Institute27 (1): 145–85.
JoNathanaelVallebuenoAndreaOuyangDerekHoDaniel E.. 2025. “Not (Officially) in My Backyard: Characterizing Informal Accessory Dwelling Units and Informing Housing Policy With Remote Sensing.” Journal of the American Planning Association91 (1): 30–45. https://doi.org/10.1080/01944363.2024.2345730
LiebigPhoebe S.KoenigT.PynoosJ.. 2006. “Zoning, Accessory Dwelling Units, and Family Caregiving: Issues, Trends, and Recommendations.” Journal of Aging & Social Policy18 (3-4): 155–72. https://doi.com/10.1300/J031v18n03_11
62.
MarantzNicholas JElmendorfChristopher SKimYoujin B.. 2024. “Overseeing Infill: How State Agencies Can More Effectively Monitor Local Land Use Administration.” Journal of the American Planning Association90 (3): 421–33. https://doi.org/10.1080/01944363.2023.2255580
63.
MarantzNicholas JWegmannJake. 2024. ““Missing” No More: Planners Should Harness Private Developers to Build Middle Housing.” Journal of the American Planning Association91 (2): 1–7. https://doi.com/10.1080/01944363.2024.2401372
64.
McHughKaileen.2022. “So you Want to Sell Your Backyard: An Analysis of Small-Scale Detached Condominium Developments in Austin, TX.” Master's thesis, University of Texas, Austin.
65.
MukhijaVinit.2022. Remaking the American Dream: The Informal and Formal Transformation of Single-Family Housing Cities. Cambridge, MA: MIT Press.
66.
MukhijaVinitCuffDanaSerranoKimberly. 2014. Backyard Homes & Local Concerns: How Can These Concerns Be Better Addressed?Los Angeles, CA: cityLAB, UCLA Department of Architecture and Urban Design.
NiedtChristopherAnackerKatrin B.. 2016. “Accessory Dwellings on Long Island: An Overview.” Hempstead, NY: Hofstra University Suburban Studies Center. licf.org/wp-content/uploads/2019/12/ADU-Report-posted.pdf
SalvadorAshley.2020. “Detached Accessory Dwelling Units–Who Benefits and who Pays?” Master's thesis, University of Waterloo, Waterloo, Ontario, Canada.
SmithDoug.2024. “The gambit to preserve a three-generation legacy of affordable rents in Cypress Park.” The Los Angeles Timeswww.latimes.com/california/story/2024-12-12/the-gambit-to-preserve-a-three-generation-legacy-of-affordable-rents-in-cypress-park.
VolkerJamey MBHandySusan. 2023. “Exploring Homeowners’ Openness to Building Accessory Dwelling Units in the Sacramento Metropolitan Area.” Journal of the American Planning Association89 (1): 45–60. https://doi.org/10.1080/01944363.2022.2036222
WegmannJakeNemirowAlison. 2011. Secondary units and urban infill: A literature review. web.archive.org/web/20220320113312/http://iurd.berkeley.edu/wp/2011-02.pdf.
