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An accessory dwelling (AD) is a complete independent dwelling unit, with kitchen and bath, on a lot that has a main dwelling. The AD must fall under the same ownership as this main dwelling. ADs are designed, arranged, used, or intended for occupancy by not more than three (3) persons for living purposes. ADs must meet the standards of §12.9.2 of the Zoning Ordinance.
Considered an accessory (or subordinate) use, ADs promote a greater diversity of housing and household types in single-family neighborhoods, while maintaining neighborhood character and underlying zoning. In Arlington, ADs serve as an important component of the Affordable Housing Master Plan and can take multiple forms:
- Within a detached accessory building (ex: detached garage)
- Within or attached to the main dwelling (ex: a basement apartment or an addition)
An application for an AD Permit must comply with the use standards of §12.9.2 of the Zoning Ordinance, which establishes the requirements for the creation, approval, and use of all ADs. An application for an AD Permit must also comply with the coverage, density, and dimensional requirements noted in §3.2 and §5 of the Zoning Ordinance.
Review Process and Follow-Up Activities
- Allow approximately thirty (30) days to process an AD Permit after the application is accepted as complete by the Zoning Division.
- Zoning Division staff will perform a preliminary review. Next, the Zoning Administrator will review the application.
- If no issues are identified, the Zoning Administrator will sign and issue the AD Permit.
- After the completion of several follow-up activities (a-c), the AD Permit will allow an accessory dwelling to be occupied on the property. The applicant must file for a Residential Building Permit (and associated trade permits) with the Inspection Services Division (ISD). The Chief Building Official (or other appropriate ISD staff) will issue the Building Permit, as well as permits for associated trades (i.e., electrical, mechanical, plumbing, etc.).
NOTE: The applicant may apply for a Residential Building Permit at the same time that s/he submits the application for an AD Permit to the Zoning Division. However, the Building Permit cannot be issued until after the Accessory Dwelling Permit is issued. Proof of recording of the Declaration of Covenants is also required prior to issuance of the Building Permit. It is typically recommended that the application for an AD Permit be submitted online via Permit Arlington at least two (2) weeks prior to the submission of the application for the associated Building Permit. Once a Building Permit is issued, construction can proceed. Upon its completion, applicants must file for a Certificate of Occupancy (CO) with the Zoning Division. Staff from ISD and the Zoning Division will conduct inspections of the AD.
- Prior to the issuance of a CO, the applicant must file an Affidavit of Compliance (see “c” above) with the Zoning Administrator. The Affidavit of Compliance is typically emailed to the Zoning Plan Reviewer who is reviewing the AD Permit. It may also be emailed to the Zoning Plan Reviewer who is reviewing the Building Permit if it is not submitted earlier in the review process.
NOTE: The Affidavit of Compliance must be re-filed if/when structural alterations are made to the AD and if/when ownership of the main dwelling changes.
- Once the Affidavit of Compliance is accepted, the Chief Building Official and the Zoning Administrator will issue the CO. At this point, the AD is complete and ready for occupancy.
Once all permits for a project have been approved, you must schedule inspections to ensure the safety and proper progress of the project. Staff from the Zoning Division and Inspection Services Division conduct inspections for ADs.
Please note that the Zoning Administrator (or his/her designee) reserves the right to conduct an annual inspection of the AD to ensure ongoing compliance with the use standards established in §12.9.2 of the Zoning Ordinance, as well as the ability of Zoning Enforcement staff to investigate compliance with the AD use standards in response to a complaint.
Fee schedules provide the range of fees charged for each type of application or activity related to land development in Arlington. Fees cover permitting, plan review, enforcement, inspection, service delivery, performance agreements, and conditions. There are separate fee schedules for the Inspection Services Division (ISD), Zoning, and the Department of Environmental Services (DES). Some permits involve fees from more than one schedule.