Accessory Structures in Anne Arundel County, MD (2026)
7 county-level rules, plus city-specific rules for 1 city in Anne Arundel County, Maryland.
Verified from official government sources
ADU Rules
Anne Arundel County allows one accessory dwelling unit per lot in an attached suite, garage, or detached structure, capped at 800 square feet or half the main home's floor area.
Anne Arundel County Accessory Dwelling Unit Rules
Some RestrictionsAnne Arundel County Code § 18-10-124
An accessory dwelling unit shall comply with all of the following requirements. (1) No more than one accessory dwelling unit per lot is allowed. ... (4) An accessory dwelling unit located in a detached structure may not exceed the lesser of 800 square feet or 50% of the floor area of the principal single-family detached dwelling. ... (5) An accessory dwelling unit shall have a separate entrance...
ADU Impact Fees
Anne Arundel County exempts accessory dwelling units from development impact fees, but only if the ADU isn't built alongside a new principal single-family house.
ADU Impact Fee Exemption in Anne Arundel County
Light RestrictionsAnne Arundel County Code § 17-11-203(c)(1)(viii)
(c) Exemptions. (1) Subject to the conditions set forth in paragraphs (2) and (3) of this subsection, the following shall be exempt from impact fees: ... (viii) accessory dwelling units, provided that the accessory dwelling unit is not constructed during the new construction of a principal single-family detached dwelling.
ADU Owner Occupancy
Anne Arundel County allows one accessory dwelling unit per lot and only requires owner-occupancy of the principal home or the ADU when either unit is used for a short-term rental; ADUs used as ordinary long-term housing carry no occupancy requirement.
Anne Arundel ADU Owner-Occupancy for Rentals
Some RestrictionsAnne Arundel County Code § 18-10-124(7)-(8)
(7) The principal single-family detached dwelling or accessory dwelling unit may be used for short-term residential rentals, as defined in Article 11 of this Code, if the principal single-family detached dwelling or accessory dwelling unit is owner-occupied. (8) An accessory dwelling unit in use and in compliance with the provisions of this section prior to May 27, 2023 is not subject to subsec...
ADU Rental Restrictions
Anne Arundel County allows one accessory dwelling unit per lot, but the ADU or the principal home may be rented short-term only while the owner lives on site.
Anne Arundel County ADU Rental Restrictions
Some RestrictionsAnne Arundel County Code § 18-10-124(7)
(7) The principal single-family detached dwelling or accessory dwelling unit may be used for short-term residential rentals, as defined in Article 11 of this Code, if the principal single-family detached dwelling or accessory dwelling unit is owner-occupied.
Shed & Carport Rules
In Anne Arundel County, a detached shed under 150 square feet and 10 feet tall accessory to a house needs no building permit, unless it sits in the Chesapeake Bay Critical Area, where a permit is always required regardless of size.
Anne Arundel County Shed Size, Setback & Permit Rules
Some RestrictionsAnne Arundel County Code, Construction Code Administrative Provisions § 105.2.1.1.1 (Art. 15 Construction and Property Maintenance Codes Supplement)
105.2.1.1.1 One-story detached accessory structures used as tool and storage sheds, playhouses, gazebos, pavilions, and pergolas, provided the average height does not exceed 10 feet and the floor area does not exceed 150 square feet if accessory to a residential structure, except that permits are required for accessory structures located in the critical area.
Garage Conversions
Converting a garage into living space counts as an accessory dwelling unit under Anne Arundel County Code § 18-10-124, capped at 800 square feet or 50% of the main house's floor area, and requires a building permit before work begins.
Anne Arundel County Garage Conversion to ADU Rules
Some RestrictionsAnne Arundel County Code § 18-10-124(3)-(4)
(3) An accessory dwelling unit shall be located: ... (ii) in an attached or detached garage; or (iii) in a detached structure. (4) An accessory dwelling unit located in a detached structure may not exceed the lesser of 800 square feet or 50% of the floor area of the principal single-family detached dwelling. An accessory dwelling unit, or the conversion of all or part of an existing structure i...
Tiny Homes
Anne Arundel County has adopted the International Residential Code's Appendix AQ, giving tiny houses their own construction standards separate from standard one- and two-family dwelling rules, covering unincorporated communities like Glen Burnie and Severna Park.
Anne Arundel County Tiny House Construction Code
Some RestrictionsAnne Arundel County Code § 15-2-102 (Construction Code Supplement, Chapter 1 § 101.4.7)
101.4.7 Residential. The provisions of the 2021 International Residential Code for One- and Two-Family Dwellings shall apply to all matters governing the design and construction of detached one- and two-family dwellings ... and their accessory structures. The following appendices are adopted as part of the Residential Code: ... Appendix AQ "Tiny Houses", Appendix AR "Light Straw-Clay Constructi...
Accessory Structures by City in Anne Arundel County
1 cities in Anne Arundel County have their own accessory structures rules. Each link goes to that city's dedicated page with code citations.
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