18.40.022 Accessory dwelling units (ADUs).
(1) Intent. The provision of accessory dwelling units promotes an efficient use of housing and allows more flexible living environments for all residents. The following regulations are designed to meet a need for an alternative form of housing without compromising the existing character or appearance of residential neighborhoods.
(2) Eligibility. ADUs may be located in a detached accessory structure or attached within the principal dwelling. For the purposes of this subsection, the term “attached” shall mean completely within an existing principal residence, provided both dwelling units are attached by a common wall, floor, or ceiling and not simply by an attached breezeway or porch. “Detached” shall mean located in a separate accessory structure. An ADU may be allowed only on conforming lots in the R-1, R-2, R-3, P-R, C-1, C-2, C-3 and PD zoning districts; an ADU is subject to approval and conditions by the administrator; and an ADU must follow the minimum lot sizes and conditions hereafter listed:
(a) R-1, 10,000 square feet. ADU may be located in an attached or detached structure.
(b) R-2, 7,200 square feet. ADU may be located in an attached or detached structure.
(c) R-3 and P-R, 5,500 square feet. ADU may be located in an attached or detached structure.
(d) C-1, C-2, C-3 and PD, 2,500 square feet for detached structures. Attached ADUs in these zoning districts shall be permitted as listed in the district use chart, ECMC 18.40.070.
(e) PU. ADUs are prohibited.
(3) Application. The following shall be required for every accessory dwelling unit:
(a) A minimum housing inspection report from the city building official certifying that the accessory dwelling unit complies with the minimum housing code, as defined in the edition of the building code in effect in the city at the time of application, including all provisions regarding setbacks between structures. If the ADU is within the principal dwelling on the lot, the housing inspection report must certify that the entire principal structure meets the minimum housing code standards.
(b) An ADU shall be required to meet the city’s requirements for water and sewer concurrency to address increased demand on the city’s water and sewer systems stemming from increased density in residential zoning districts.
(4) Development Standards. The following development standards shall be met to qualify for the occupation of an accessory housing unit:
(a) The accessory dwelling unit must comply with all applicable provisions of the city of Electric City zoning code in effect at the time the accessory dwelling unit is approved, including setback and lot coverage requirements for the zoning district in which the accessory dwelling unit is located.
(b) Maximum occupancy of the unit shall not exceed two persons per dwelling, as defined in the edition of the International Building Code in effect in the city at the time of application.
(c) The maximum livable area of an accessory dwelling unit shall be no greater than the livable area of the principal dwelling, and shall not under any circumstances exceed 800 square feet.
(d) The owner of the lot shall provide one off-street parking space for the exclusive use of the occupants of the accessory dwelling unit, in addition to the off-street parking required for the principal dwelling. A garage or carport may provide off-street parking where, in fact, the garage or carport is usable for parking cars. All off-street parking areas shall be surfaced to provide long-term dust control.
(e) Only one ADU per conforming lot shall be permitted.
(f) Addition of an ADU shall not result in any modifications to the principal structure or the residential lot that would compromise the single-family residential character of the principal structure or be detrimental to the character of the neighborhood.
(g) All ADUs must have a separate connection to city utilities.
(5) Accessory housing units in R-1, R-2, and R-3 zoning districts must be sited so that they will conform with all applicable regulations, including setbacks. Subsequent subdivision of lots in said zones with accessory structures must meet minimum lot sizes.
(6) No accessory dwelling unit shall create a nuisance or hazard, including noise, dust, or threat to air or water quality or to the well-being of the city and the area in which the accessory use or structure is located.
(7) No accessory dwelling unit may be used as an overnight accommodation, nightly rental, or other short-term occupancy unless specifically allowed by the district use chart, ECMC 18.40.070. (Ord. 594 § 3, 2022)