An accessory dwelling unit shall comply with all of the following requirements.
(1) No more than one accessory dwelling unit per lot is allowed.
(2) An accessory dwelling unit may not be a mobile home or a manufactured home, as defined in § 11-9-101 of this Code.
(3) An accessory dwelling unit shall be located:
(i) in a separate dwelling unit in a principal single-family detached dwelling, or connected by a breezeway, open or enclosed, to a principal single-family detached dwelling;
(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.
(5) An accessory dwelling unit shall have a separate entrance.
(6) An accessory dwelling unit shall use the same street address as the principal single-family detached dwelling and shall be designated as “Unit B”.
(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 subsections (4), (5), (6), or (7), unless the accessory dwelling unit is altered or expanded after May 27, 2023.
(9) (i) Except as provided in subparagraph (ii), a variance may not be granted to reduce the minimum setback requirements to an adjacent lot located in a residential district.
(ii) A variance to reduce the minimum setback requirements to an adjacent lot located in a residential district may be granted if the variance is for a structure that was in existence before May 27, 2023 and the structure is being converted to an accessory dwelling unit.
(Bill No. 4-05; Bill No. 78-05; Bill No. 8-15; Bill No. 75-16; Bill No. 17-17; Bill No. 67-17; Bill No. 16-20; Bill No. 68-20; Bill No. 90-20; Bill No. 2-21; Bill No. 81-22; Bill No. 6-23; Bill No. 15-23)
Editor’s note - Section 2 of Bill No. 6-23 requires an annual report regarding accessory dwelling units to be prepared and sent to the County Executive and County Council.