Accessory Dwelling Units (ADU) Code Amendment Frequently Answered Questions.
Interested in building a casita?
Accessory Dwelling Units (ADU), or casitas, are now permitted in Tucson on residential lots, subject to certain regulations.
Use this ADU handout to learn more about the new regulations, and how to design and permit a casita.
Accessory Dwelling Unit code amendment adopted by Mayor and Council
Mayor and Council held a public hearing on December 7, 2021 to reconsider the code amendment to allow Accessory Dwelling Units (ADUs), which had been previously adopted on October 19, 2021. Following the hearing and their deliberations, Mayor and Council adopted an amendment to the Unified Development Code to allow ADUs, or casitas.
The code amendment adopted by Mayor & Council allows:
- One ADU to be built on any residential lot in the city (any lot with one or two homes)
- The maximum size of the ADU is up to 10% of the lot size, up to a maximum of 1,000 square feet. All lots are allowed an ADU of at least 650 square feet.
- The maximum height for ADUs is 12' or the height of the primary structure on lots with two-story homes
- All other dimensional standards regarding lot coverage and setbacks apply
- One parking space would be required per ADU, which could be waived for sites that are a quarter-mile from transit or a bike boulevard; on-street parking can also be used
- Each newly constructed ADU would be required to have a cool roof
On October 19, Mayor and Council set a 5-year sunset date for the ordinance, at which point it could be updated/renewed, or sunset from the code, as well as a review of the program in 1 year.
Mayor and Council also directed staff to develop programs to provide resources and technical support to make ADUs accessible and affordable to Tucson homeowners and residents, including a pilot program to fund ADU repairs and improvements and to establish an amnesty program for unpermitted ADUs.
- An ADU is an independent housing unit with its own kitchen, bathroom, living and sleeping space. These units are typically under 1,000-square-feet and are accessory to a primary residence.
- ADUs can be detached, attached or interior to the primary residence (i.e., through the conversion of a garage, basement, or attic).
Benefits of Accessory Dwelling Units
Accessory Dwelling Units have many benefits. This housing style can be a means to:
Increase affordable rental housing supply
Encourage more flexible housing options for seniors
Support multi-generational households and living arrangements
Provide supplemental income to landowners and promote neighborhood stability
Support climate-resilient infill development in context with existing neighborhoods
In the past decade, many cities have taken steps to legalize ADUs as a way to add to their affordable housing stock and meet other community goals. California, Oregon, and New Hampshire have enacted legislation to make this housing option available statewide.
A proposal to allow Accessory Dwelling Units in Tucson has been developed based on input from the public and a stakeholder group.
Have questions related to ADUs? Check out our ADU Frequently Asked Questions here.
Watch a video to see examples of casitas in Tucson and learn more about the proposal!
Additional information and reference materials related to the ADU project
Mayor and Council to hold a virtual public hearing to review the draft Accessory Dwelling Units (ADU) Code Amendment
On Tuesday, October 19 at 5:30pm, the Mayor and Council will hold a virtual public hearing to review the Accessory Dwelling Units (ADU) Code Amendment.
The public will have two options to provide comment to the Mayor and Council:
- Members of the public may submit written comments on any items scheduled as a public hearing. To do so, send an email to firstname.lastname@example.org. The email should include the individual’s name, and the agenda item for comment. The comments will be limited to no more than 500 words. Comments must be received by no later than 5:00 p.m., Monday, October 18, 2021.
- Individuals wishing to speak during the public hearing (subject to technological availability) will join the meeting via teleconference. You must submit a written request to email@example.com. The email should include your name, and the phone # you will use for the teleconference. The phone # will be used to identify the individual when/if being called upon to speak. Once your request to speak has been received by the City Clerk, you will be provided instructions on how to connect to the teleconference. Requests to speak must be submitted no later than 12:00 p.m., Tuesday, October 19, 2021.
View the meeting agenda
Click here to watch the hearing live.
Planning Commission recommends approval of Accessory Dwelling Units Code Amendment after Public Hearing
The Planning Commission held a virtual public hearing on Wednesday, September 15 at 6pm to take additional public comment related to the proposed amendment to the Unified Development Code to allow ADUs. After hearing from seventeen speakers, and receiving over 100 written comments, the Commission voted 9-0 to recommend the proposal as presented by staff, with additional recommendations to Mayor and Council to develop programs to provide resources and technical support to make ADUs more affordable, and evaluate the program in 24 months. Watch a recording of the meeting here:
On Wednesday, July 28, 2021, the Planning Commission held a public hearing on the proposed amendment to the Unified Development Code to allow ADUs. Staff presented the draft proposal and an overview of the process to date for the Planning Commission to review and discuss. At that meeting, the Planning Commission voted 10-0 to continue the public hearing until Wednesday, September 15, 2021 at 6 pm, to allow for the public to have additional opportunity to comment on the ADU proposal.
The following is a video recording of that meeting:
The meeting agenda and materials can be found on the Planning Commission webpage.
The presentation from that meeting may be found here.
Planning Commission Study Session on Accessory Dwelling Units
The City of Tucson Planning Commission held a study session on the proposed amendment to the Unified Development Code to allow ADUs on Wednesday, June 30 at 6 pm. Staff presented the draft proposal and an overview of the process to date for the Planning Commission to review and discuss. At that meeting, the Planning Commission voted 9-0 to set a date of Wednesday, July 28 at 6 pm, for a Public Hearing to provide the public an opportunity to comment on the ADU proposal.
The following is the video recording of that meeting:
The meeting agenda, & materials can be found on the Planning Commission webpage.
The presentation from that meeting may be found here.
Public Meetings: Accessory Dwelling Units Code Amendment Draft Proposal
What could these housing options mean for Tucson?
The City of Tucson Planning and Development Services Department recently held a series of virtual public meetings to share a proposed code change to allow backyard casitas (also known as Accessory Dwelling Units) in Tucson. Attendees heard how this housing option can provide affordable housing, help seniors age in place, and promote sustainable infill development.
Staff presented a draft proposal for new zoning regulations to permit this housing type. This proposal was developed based on what we heard at public meetings held earlier this year, and input from a stakeholder group representing a range of viewpoints and expertise. Participants had a chance to share feedback and hear from other community members.
Watch a recording of one of the meetings here:
Public Meetings to Gather Community Input
The first round of public meetings were held on February 24 and 25 for members of the public to learn more about how Accessory Dwelling Units can provide additional housing options in Tucson, how they are regulated today, and what changes are being considered in order to make this housing option more accessible. Participants also had a chance to share their thoughts and feedback. Additional meetings will be held later in the spring to share a draft proposal that will be developed based on the public input.
View meeting video
On Tuesday, November 17, 2020, Mayor and Council directed Planning and Development Services to begin the process of amending the Unified Development code to define and permit Accessory Dwelling Units (aka casitas), identify the zones where they are appropriate and create development standards regulating unit size, height, minimum lot size, maximum lot coverage, setbacks, parking requirements and other relevant aspects in order to promote this affordable housing option in a manner that is compatible with existing neighborhoods. This process will involve extensive public outreach and engagement. Follow the process here to learn how to get involved.
View the presentation that was shared with Mayor and Council here.
Why are ADUs being considered in Tucson?
This proposed code amendment stems from and supports ongoing analysis and policy recommendations related to housing needs and sustainability goals in our community.
The City of Tucson has been working with Pima County on a Housing Study to understand our local housing market and identify gaps in our housing stock. Initial findings show that over half of renter households and over 22% of homeowner households are housing cost burdened, meaning they spend more than 30% of household income on housing costs (i.e. rent, mortgage, property tax, utilities). ADUs can often be an affordable housing option. As a smaller living space, the cost of renting an ADU can be lower than that of a larger apartment. Additionally, adding to the overall supply of housing across the city tends to promote stable rent levels.
On June 9, 2020, Mayor and Council directed staff to form a Commission on Equitable Housing and Development. This Commission has been tasked with providing advice to the Mayor and Council on topics such as: how the City can increase city investment in housing; how to preserve affordability while increasing housing production/ stock; and how to protect barrios and communities from rapid change and displacement.
On September 9, 2020, Mayor and Council adopted a Climate Emergency Declaration calling for carbon neutrality by 2030 and the development of climate adaptation and mitigation strategies. ADUs can be an important tool to support compatible residential infill development. ADUs represent an efficient use of existing infrastructure by adding new housing in already developed areas. As a smaller footprint housing option, ADUs are typically energy efficient structures. Furthermore, these units are often developed in central neighborhoods with multi-modal transportation options. ADUs are an important means to retrofit our neighborhoods to be more climate-resilient.
The Age Friendly Tucson Action Plan was adopted by Mayor and Council in May 2019. Goals of this plan include providing affordable housing options for older adults and to facilitate older adults and people with disabilities aging in place. ADUs are a way to support these goals, as they can be an affordable option for seniors, and also support aging in place and aging in proximity to family and caregivers.
How are ADUs currently regulated in Tucson?
“Accessory dwelling unit” is not a defined term in the Unified Development Code (UDC). In fact, the code currently states that accessory structures within residential zones may not be a dwelling unit.
Accessory sleeping quarters/guest house are allowed, provided other regulations are met, however, a full kitchen in the unit is not permitted, as sleeping quarters are not intended to be a self-contained unit.
A second dwelling unit is allowed in certain districts, depending on the lot size and ability to meet other zoning regulations. Minimum lot size requirements and density regulations make it difficult to develop ADUs on most standard size lots in urban residential districts.
|Meeting Type||Presentation||Meeting Notes||Link to Video|
|Planning Commission Public Hearing - July 28, 2021||Click here|
|Planning Commission Study Session - June 30, 2021||Click here|
|2nd Public Meetings - May 19, 22, 24 & 25, 2021||Click here||Meeting Summary|
|1st Public Meetings - February 24 & 25, 2021||Click here||Meeting Summary|
- October 19, 2021 - "Tucson now allows accessory buildings at residences", KOLD
- September 2, 2021 KGUN News Story
- July 28, 2021 - KGUN News Story
- February 25, 2021 - KOLD News Story
Newspaper / Magazines
- November 18, 2021 - "Tucson City Council delays law allowing backyard casitas", Arizona Daily Star
- October 24, 2021 - "Tucson will now allow backyard casitas after City Council vote", Arizona Daily Star
- September 26, 2021 - "City commission endorses Tucson's plan to allow for backyard casitas," Arizona Daily Star
- August 29, 2021 - Arizona Daily Star Letter to the Editor
- August 22, 2021 – "Tim Steller's opinion: Casita boom should be welcome in expensive Tucson," Arizona Daily Star Opinion
- August 11, 2021 – Arizona Daily Star Letter to the Editor
- August 7, 2021 – "Tucson considers allowing casitas with kitchens to ease affordable housing shortage," Arizona Daily Star
- August 4, 2021 – Arizona Daily Star Letter to the Editor
- August 1, 2021 – "Jonathan Hoffman: Tucson should OK 'Accessory Dwelling Units' (aka casitas)," Arizona Daily Star Opinion
- July 29, 2021 – Tucson Sentinel Opinion
- July 8, 2021 – High Country News
- May 29, 2021 – Arizona Daily Star Letter to the Editor
- May 29, 2021 – Arizona Daily Star Opinion
- May 28, 2021 – "Tucson considers making room for more casitas," Arizona Daily Star
- February 24, 2021 – KOLD News Story
- November 12, 2020 – KOLD News Story
- October 18, 2021 - "Tucson develops plan to allow for more casitas", Arizona Public Media
- September 1, 2021 - Tipping Point with Zach Yentzer
- July 22, 2021 - KJZZ Radio Program
- AARP ADU Website
- The ABCs of ADUs: A guide to Accessory Dwelling Units and how they expand housing options for people of all ages
- AARP Accessory Dwelling Units Model State Act and Local Ordinance
- Jumpstarting the Market for Accessory Dwelling Units: Lessons Learned from Portland, Seattle and Vancouver
- "The Evolving World of ADU Regulations" webinar by Donald Elliott
- Accessory Dwellings Website
- Accessory Dwelling Units: A Step by Step Guide to Design and Development
- Oregon Metro Build Small Coalition Accessory Dwelling Unit zoning code audit report
- Florida Housing Accessory Dwelling Unit Guidebook