Accessory Dwelling Unit (ADU)

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.