Anne Arundel County, MD Accessory Structures: Garage Conversions (2026)
Garage conversion rules in Anne Arundel County, MD, sometimes called garage-to-ADU or accessory living unit conversions, govern permits, ceiling height, egress, and parking replacement.
Key Facts
- Size cap
- 800 sq ft or 50% of house
- ADUs per lot
- One per lot
- Entrance
- Must have separate entrance
- Permit
- Building permit required
- Grandfathered units
- Pre-May 27, 2023 exempt from size rule
Summary
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.
(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 into an accessory dwelling unit, shall be constructed pursuant to any permits required by this Code.
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: 2026 S-93: County Code is current through May, 2026).
Full Breakdown
Anne Arundel County treats a garage converted to living space as an accessory dwelling unit under County Code § 18-10-124. The ADU must have its own entrance, use the same street address designated Unit B, and, if in a detached garage, stay under 800 square feet or 50% of the principal home's floor area, whichever is smaller. Only one ADU is allowed per lot, and the conversion needs a building permit under the County Code before work starts. This is the only local rule for unincorporated communities like Glen Burnie and Severna Park; there is no separate municipal permit process.
Violations & Fines
Converting a garage without a permit, exceeding the 800-square-foot or 50% size cap, or skipping the separate entrance and Unit B address requirement violates § 18-10-124 and can force removal or legalization of the unpermitted conversion.
Frequently Asked Questions
Can I convert my garage in Glen Burnie into an apartment?
Do I need a permit to convert a garage to living space?
Sources & Official References
Other rules in Anne Arundel County
Compare Anne Arundel County to another location·View the Maryland accessory structures overview
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