One Accessory Dwelling Unit (ADU) may be approved in any base zoning districts as an accessory use to a principal single-family dwelling unit if all conditions listed in Sec. 54-214 of the City of Charleston Zoning Ordinance are met.
An ADU is defined as, "a dwelling unit providing complete, independent living facilities for no more than two (2) adults that is separate from, and subordinate to, the principal dwelling unit, and located in the same building as the principal dwelling unit or in an accessory building on the same lot. This definition includes garage apartments."
Conditions for approval include, but are not limited to, the following:
- Either the principal structure or the ADU must be owner-occupied. If the ADU is to be rented for compensation, monetary or otherwise, the ADU must meet Affordable Housing income and rental thresholds as defined in Sec. 54-120 of the City of Charleston Zoning Ordinance (household income of no more than 80% of median area income).
- Neither the principal dwelling unit nor ADU shall be utilized for Short Term Rental.
- The property shall not be converted into Horizontal Property Ownership Regime.
- Applicant shall provide a copy of a recorded covenant affidavit that certifies that no covenants exist that would prohibit the construction of an ADU.
- One parking space shall be provided in addition to parking required for existing uses on property.
- Each ADU is limited to 850 square feet of conditioned floor space.
- ADU occupancy is limited to no more than two (2) adults.
- A covenant shall be recorded that memorializes the ADU conditions.
An Accessory Dwelling Unit (ADU) may be approved in all base zoning districts, as an accessory use to a principal single-family dwelling, if all of the following conditions are met:
• A scaled site plan that shows all the information listed on the ADU application;
• A Recorded Covenant Affidavit that certifies that no covenants exist that prohibit the construction of an ADU;
• Limited to one ADU per lot, with a maximum of two (2) dwelling units per lot, including the ADU.
• Each ADU shall be limited to 850 square feet of conditioned floor area, except that:
1. When the ADU is located above a detached garage approved using the setback exceptions listed in Sec. 54-506 f. of the City of Charleston Zoning Ordinance, the maximum footprint shown in Sec. 54-506, f. still applies.
2. When the ADU is located on the ground level and attached to or located within a detached accessory building approved using the exceptions listed in Sec. 54-506, f. of the City of Charleston Zoning Ordinance, the building footprint shall not exceed 600 square feet.
• One (1) off-street parking space shall be provided for the occupants of the ADU on the subject property in addition to providing on the subject property, off-street parking required for the existing uses on the property. Parking may be situated in tandem.
• The following conditions shall be memorialized in a recorded covenant to run with the property. A copy of the recorded covenant must be provided to the Department of Planning, Preservation and Sustainability prior to the issuance of a building permit:
1. Either the principal structure or the ADU must be owner-occupied. If neither unit is owner-occupied, the ADU may not be rented separately from the principal dwelling unit. No subleases of the ADU are permitted;
2. If rented for compensation, monetary or otherwise, the ADU must meet the Affordable Housing income and rental thresholds, as defined in Sec. 54-120 of the City of Charleston Zoning Ordinance;
3. Occupancy of the ADU shall be limited to no more than two (2) adults with “adult” defined as any person eighteen years of age or older;
4. Under no circumstances shall the property be converted into a horizontal property ownership regime;
5. Neither the principal dwelling unit nor ADU shall be utilized for Short Term Rental;
6. The covenants shall accord the City of Charleston, or its assignee, rights to enforcement by any legal and/or equitable means, including the revocation of a certificate of occupancy.