Chapter 16 — ACCESSORY DWELLING UNITS

Sections:

16.010 Intent. 16.015 Consistency with State Law. 16.020 Definition. 16.030 Applicable Land Use Designations. 16.040 General Provisions. 16.050 Standards for Accessory Dwelling Units.

The intent of this chapter is to allow for Accessory Dwelling Units in accordance with State law in order to provide additional affordable housing opportunities, including housing for the elderly in Mono County.

This chapter is consistent with State Law, including AB 881, AB 670, AB 587, AB 671, AB 68, and SB 13.

"Accessory Dwelling Unit" (also referred to as "dependent," “Secondary Housing,” or "granny unit") means residential occupancy of a living unit located on the same parcel as the primary residential unit. It provides complete, independent living facilities for one or more persons including permanent provisions for living, sleeping, eating, cooking, and sanitation on the same parcel as the primary unit is situated. An Accessory Dwelling Unit shall meet the minimum regulations for an efficiency dwelling unit in the California Building Code.

The Accessory Dwelling Unit can be either attached to or detached from the primary residential unit but in either case shall have similar architectural elements as the primary unit (i.e., materials, textures, colors, etc.; see 16.050 G below). The Accessory Dwelling Unit shall be clearly subordinate to the primary unit.

“Junior accessory dwelling unit” means a unit that is no more than 500 square feet in size and contained entirely within an existing single-family structure. A junior accessory dwelling unit may include separate sanitation facilities, or may share sanitation facilities with the existing structure. The junior accessory dwelling unit must contain cooking facilities.

Utilities that are installed for future expansion, such as stub outs that would allow a kitchen to be installed at a later date, shall be considered as complete cooking facilities in accessory dwelling units. In units required by deed restriction, complete cooking facilities shall be installed resulting in a usable kitchen at final permit issuance, and interior access between attached units shall be no more than a single personnel door.

An Accessory Dwelling Unit and Junior Accessory Dwelling Unit may be permitted in any land use designation that allows single-family residences as a permitted use or as allowed in Specific Plan (SP) areas subject to the General Provisions below.

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LAND USE ELEMENT

• A. Accessory Dwelling Units are permitted with a building permit if any of the following instances apply:

  • (i) The accessory dwelling unit or junior accessory dwelling unit is located within a single-family dwelling or existing space of a single-family dwelling, whether existing or proposed, or accessory structure and may include an expansion of not more than 150 square feet beyond the physical dimensions of the existing accessory structure. An expansion beyond the physical dimensions of the existing accessory structure shall be limited to accommodating ingress and egress. The space must have exterior access. Side and rear setbacks must meet fire protection standards and prevent snow shedding onto adjacent properties.

  • (ii) One-bedroom detached accessory dwelling units not exceeding 850-square feet and twobedroom accessory dwelling units not exceeding 1,000-square feet. The unit may not exceed four-foot side and rear yard setbacks and must meet health and safety standards, including prevention of snow shedding onto adjacent properties.

  • (iii) Multiple accessory dwelling units within the portions of existing multifamily dwelling structures not used as livable space including, but not limited to, storage rooms, boiler rooms, passageways, attics, basements, or garages, if each unit complies with state building standards for dwellings. An existing multifamily unit is allowed at least one accessory dwelling unit or up to, and not exceeding, 25 percent of the existing multifamily dwelling units.

  • (iv) Not more than two accessory dwelling units that are located on a lot that has an existing multifamily dwelling, but are detached from that multifamily dwelling. Side and rear yard setbacks may be reduced to four feet provided the design demonstrates snow will not shed onto adjacent properties and fire safety standards are met.

• B. The following accessory dwelling units that do not qualify under 16.040A may be permitted through Director Review:

  • (i) One-bedroom units between 850 and 1,400-square feet;

  • (ii) Two-bedroom units between 1,000 and 1,400-square feet.

• C. Accessory dwelling units that do not qualify under 16.040A and exceed 1,400-square feet may be permitted through Use Permit.

• E. Square footage of accessory dwelling units shall be calculated based on the exterior dimensions of the unit. All interior living space shall count toward the total square footage of the unit.

• F. Consistent with Government Code section 65852.2, ministerial reviews shall occur within 60 days after receiving an accessory dwelling unit application, unless the accessory dwelling unit is built concurrently with the primary unit.

• A. All construction shall conform to the height, setback, lot coverage, fees (including school impact fees and fire district fees), snow storage, and other development requirements applicable to residential construction in the land use designation in which the property is located. Side and rear yard setbacks may be reduced to four feet provided the design demonstrates snow will not shed onto adjacent properties. The unit shall be exempt from development impact fees if less than 750-square feet and all units are exempt from Housing Mitigation Ordinance (HMO) fees.

• B. If a well and/or septic system is/are to be utilized, a clearance letter shall be obtained from the Environmental Health director and shall accompany the building permit application (or if applicable, the Director Review or Use Permit application). For Accessory Dwelling Units that are served by a public water and/or sewer system, a letter from the serving entity that indicates adequate service shall be submitted as part of the application.

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MONO COUNTY GENERAL PLAN

• C. One of the units on the parcel must be owner occupied if the property contains a junior accessory dwelling unit (either the primary unit or the junior accessory dwelling unit); for detached accessory dwelling units, there is no owner occupancy requirement. For units that do not qualify under 16.040.A, one unit on the property must be owner occupied.

• D. Required parking shall be one space for a one-bedroom unit and two spaces for units of two or more bedrooms, and is in addition to the required parking for the primary unit. There is no parking requirement for studio units. No parking standards shall be imposed in the following instances:

(1) The accessory dwelling unit is located within one-half mile of public transit.

(2) The accessory dwelling unit is located within an architecturally and historically significant historic district.

• (3) The accessory dwelling unit is part of the existing primary residence or an existing accessory structure.

• (4) When on-street parking permits are required but not offered to the occupant of the accessory dwelling unit.

(5) When there is a car-share vehicle located within one block of the accessory dwelling unit.

• E. Whether attached or detached, the Accessory Dwelling Unit shall be architecturally compatible with the primary residence. The Community Development Department shall determine the architectural compatibility of the structures and shall consider roofing, siding, trim, door and window frame colors; and materials; roof slope and pitch; and wall articulation, roof line articulation, eaves, railings, chimneys, porches, and similar features; landscaping should also be considered in helping to make the units compatible. The Accessory Dwelling Unit shall be clearly subordinate to the primary unit in terms of size and placement on the property. If attached, the two units shall have the appearance of a singlefamily residence; the Accessory Dwelling Unit entrance shall be located on the side or rear of the building.

and similar features; landscaping should also be considered in helping to make the units compatible. The Accessory Dwelling Unit shall be clearly subordinate to the primary unit in terms of size and placement on the property. If attached, the two units shall have the appearance of a singlefamily residence; the Accessory Dwelling Unit entrance shall be located on the side or rear of the building.

• F. Pursuant to the California Building Code, accessory dwelling units shall not be required to provide fire sprinklers if they are not required for the primary residence. Accessory dwelling unit utility connections and related fees shall comply with Government Code section 65852.2.

• G. No passageway shall be required in conjunction with the construction of an accessory dwelling unit. No setback shall be required for an existing garage that is converted to an accessory dwelling unit, and a setback of no more than four feet from the side and rear lot lines shall be required for an accessory dwelling unit that is constructed above a garage, provided the design demonstrates snow will not shed onto adjacent properties and fire safety standards are met.

• H. Short-term rentals are prohibited in all accessory dwelling units.

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DEVELOPMENT STANDARDS