(a)

To increase the variety and flexibility of Sheridan's existing housing stock;

(b)

To maintain the predominately residential character of Sheridan's single-family neighborhoods;

(c)

To allow homeowners additional rental opportunities for supplemental income.

(Ord. No. 10-2021, § 1, 11-8-2021)

The following words, terms and phrases, when used in this article, shall have the meanings ascribed to them in this section, except where the context clearly indicates a different meaning:

Accessory dwelling unit, or ADU, means an independently accessed one-household dwelling unit on the same lot as a single-family dwelling unit and is coincident with all definitions and requirements of a dwelling unit as defined by the building and fire codes as adopted by the City of Sheridan.

Attached accessory dwelling unit means an accessory dwelling unit which shares at least 25 percent of its wall length with a single-family dwelling unit and expands the footprint of the single-family dwelling unit.

Building envelope means the three-dimensional space created from the exterior surfaces of all walls, floors, and roofs of a building.

Detached accessory dwelling unit means an accessory dwelling unit which shares no wall length with a single-family dwelling unit and which has a completely separate footprint.

Footprint means the two-dimensional land area covered by a building or structure calculated to the edges of the roof or eaves of the building or structure.

Interior accessory dwelling unit means an accessory dwelling unit which is contained completely within the building envelope of a single-family dwelling unit.

Short-term rental means any dwelling, dwelling unit or portion of any dwelling unit rented or leased for valuable consideration to a particular person or persons for periods of time less than 30 days.

Single-family dwelling unit means a building created and used for the purposes of housing a single household which is not attached in any way to another dwelling unit.

(Ord. No. 10-2021, § 1, 11-8-2021)

(a)

Accessory dwelling units are allowed in the residential single-family (RES-SF), residential single-family large lot (RES-SFLL), and residential multi-family (RES-MF) districts only in conjunction with a single-family dwelling unit.

(b)

Accessory dwelling units are not permitted on any property with existing two-family (duplex) or multi-family dwelling units.

(c)

Only one accessory dwelling unit is permitted per lot and only in conjunction with a single-family dwelling unit.

(d)

A maximum of one short-term rental license may be issued, pursuant to the home-based business regulations of section 56-112(a)(5), for any property with an accessory dwelling unit for either the accessory dwelling unit or the single-family dwelling unit but not both, as long as the property owner occupies one of these units.

(e)

Short-term rentals are not permitted unless the property owner occupies one dwelling unit on the property.

(f)

A maximum of two long-term residential rental licenses (lease terms greater than 30 days) may be issued to a property owner for the rental of an accessory dwelling unit and single-family dwelling unit, with a separate business license required for each rental.

(Ord. No. 10-2021, § 1, 11-8-2021)

(a)

Accessory dwelling units may not contain more than one household dwelling unit, as defined by section 56-3 of the Code.

(b)

The combined lot coverage of the single-family dwelling unit, any accessory buildings, and an accessory dwelling unit may not exceed the lot coverage maximum of the underlying zone district.

(c)

An existing building envelope that is to be renovated to accommodate an accessory dwelling unit shall not be subject to the lot coverage, height, or setback requirements of the underlying zone district, provided that the following are satisfied:

(1)

The building envelope will not be expanded.

(2)

The existing envelope can accommodate the accessory dwelling unit without complete demolition and replacement of the walls, floor, and roof.

(d)

No subdivision of an accessory dwelling unit from the existing single-family dwelling unit is permitted, unless the proposed subdivision meets all standards for the underlying zone district.

(Ord. No. 10-2021, § 1, 11-8-2021)

(a)

An accessory dwelling unit may be created by the conversion of existing space within a building envelope or the creation or expansion of a building footprint only through the review, approval, and issuance of a building permit and the receipt of a certificate of occupancy (CO) from the City of Sheridan.

(b)

Prior to the submission of a building permit application for the creation of an accessory dwelling unit, the applicant must submit a pre-planning application request for the proposed accessory dwelling unit and shall include the following:

(1)

Dimensioned site plan and floor plan.

(2)

A letter of intent addressing compliance with this article.

(3)

Proof of ownership of the property or authorization from the owner of the property.

(c)

An applicant may only submit a building permit application for an accessory dwelling unit after comments are issued on the pre-planning application by the zoning administrator.

(d)

All applications (to include pre-planning and building permit) shall identify the type of accessory dwelling unit requested and demonstrate compliance with the type-specific regulations in a narrative format.

(e)

All building permit applications for accessory dwelling units are subject to review and approval by the zoning administrator.

(f)

Building permit applications that do not meet the requirements of this article or the Code may be denied by the zoning administrator.

(g)

Existing, non-conforming dwelling units meeting the definition of an accessory dwelling unit may be brought into compliance with the zoning and building codes of the City of Sheridan through the approval process set forth in this section.

(Ord. No. 10-2021, § 1, 11-8-2021)

(a)

Accessory dwelling units shall be connected to municipal utility systems, including, but not limited to, the following: sanitary sewer, water, gas, and electric.

(b)

An accessory dwelling unit shall not be connected to a septic system, well water, or propane tank, even if the existing single-family dwelling unit is connected to any of the above systems.

(c)

Accessory dwelling units shall follow the requirements of the appropriate utility district(s) in connecting to utility systems.

(d)

Will-serve letters from the appropriate water, sanitary sewer, and gas and/or electric districts or utility providers shall be submitted with a building permit application for an accessory dwelling unit to be deemed a complete permit application for review by the zoning administrator.

(Ord. No. 10-2021, § 1, 11-8-2021; Ord. No. 11-2025, § 2, 6-23-2025)

The following types of accessory dwelling units are permitted:

(a)

Interior accessory dwelling units:

(1)

Height and setback requirements are based on the underlying zone district for the principal building.

(2)

Interior accessory dwelling units are limited to 800 square feet in area.

(b)

Attached accessory dwelling units:

(1)

Height and setback requirements are based on the underlying zone district for the principal building.

(2)

Attached accessory dwelling units are limited to 800 square feet in area.

(3)

Architectural compatibility is required for attached accessory dwelling units and must be achieved through one of the techniques contained in the supplementary standards.

(c)

Detached accessory dwelling units:

(1)

Detached accessory dwelling units shall not be located in front or side yards and shall only be located in rear yards.

(2)

Minimum side and rear setbacks are five feet to lot line, with an additional six inches of side and rear setback for every foot of height over 15 feet.

(3)

Minimum internal setback between the accessory dwelling unit and the single-family dwelling unit on the same lot is five feet.

(4)

Height cannot exceed 25 feet or the height of the principal structure, whichever is less.

(5)

Detached accessory dwelling units are limited to 800 square feet in area.

(6)

Detached accessory dwelling units are limited to 1,000 square feet in area for lots which exceed 10,000 square feet in lot area.

(7)

Architectural compatibility is required for detached accessory dwelling units and must be achieved through one of the techniques contained in the supplementary standards.

(Ord. No. 10-2021, § 1, 11-8-2021)

(a)

The city may require a new parking spot to be constructed or available for each accessory dwelling unit under the following two circumstances only:

(1)

The city may require the designation of an existing parking space on the lot for the use of the accessory dwelling unit so long as such a parking space already exists at the time the accessory dwelling unit is constructed or converted.

(2)

The city may require the construction of a new off-street parking space if:

a.

The accessory dwelling unit is in a zone district that, as of January 1, 2024, required one or more off-street parking spaces for a single-unit detached dwelling; and

b.

There is no existing parking space on the lot (including a driveway, garage, or tandem parking space) that could be used for the accessory dwelling unit; and

c.

The accessory dwelling unit is located on a block where the city prohibits on-street parking.

(b)

The minimum floor area for any accessory dwelling unit shall be 150 square feet.

(c)

The area of enclosed garages or carports shall not be included in calculating the area of the accessory dwelling unit.

(d)

Architectural compatibility is required for attached and detached accessory dwelling units and may be achieved by demonstrating that a minimum of one of the following standards are met through the pre-planning and building permit application processes:

(1)

Use of the same primary exterior material as the single-family dwelling unit;

(2)

Use of the same roof shape as the single-family dwelling unit; or

(3)

Consistent use of the same exterior colors, fixtures (lighting, gutters, etc.) or fenestration as the single-family dwelling unit.

(e)

Addresses shall be assigned to all accessory dwelling units on the city's standard address request form, and shall designate the single-family dwelling unit as "A" and the accessory dwelling unit as "B."

(Ord. No. 10-2021, § 1, 11-8-2021; Ord. No. 11-2025, § 3, 6-23-2025)