This Article provides standards and criteria for regulating accessory development. Accessory development includes accessory uses, buildings and structures. Examples of accessory development include, but are not limited to, patios, decks, sheds, shops, detached garages and carports, accessory dwellings, home businesses, and family day care.
(Ord. 19-1373; Ord. 20-1379)
Accessory development shall be subject to the same requirements as the principal uses with each zone district except as otherwise provided below:
A. 
Nonconforming Development. Accessory development involving nonconforming uses, buildings and structures is subject to the requirements of Article 3.090: Nonconforming Development.
B. 
Size. Accessory development shall be subordinate in size to the primary use.
C. 
Location.
1. 
A required side or rear yard setback may be reduced to 3 feet for detached accessory buildings or structures that do not require a building permit, except as allowed in paragraph 3 below. The distance shall be measured from the common property line to the building or structure's eve line.
2. 
Garage and carports accessory to residential uses with vehicle entrances facing a side street shall be set back a minimum of 20 feet from the property line.
3. 
Rear yard or side yard setbacks for garage/carports on alleys may be waived per the following:
a. 
Garage/carports opening onto alleys with established 20-foot rights-of-way may be set back zero feet from the right-of-way.
b. 
Garage/carports opening onto alleys with less than a 20-foot right-of-way shall be set back to a minimum building line located 10 feet from the center of the alley right-of-way.
4. 
No rear yard setback is required for detached accessory buildings if the rear yard abuts an alley that has at least a 20-foot right-of-way. If the alley right-of-way is less than 20 feet in width, detached accessory structures that may be located up to 10 feet from the center line of the right-of-way.
D. 
Height. The height of accessory structures shall not exceed 80% of the primary structure's height, or 18 feet, whichever is higher.
(Ord. 19-1373; Ord. 20-1379)
Accessory dwelling units (ADU) are allowed in certain situations to:
A. 
Create new housing units while respecting the look and scale of a single-family development;
B. 
Increase the housing stock of existing neighborhoods in a manner that is less intense than alternatives;
C. 
Allow more efficient use of existing housing stock and infrastructure;
D. 
Provide a means for residents, particularly seniors, single parents, and families with grown children, to remain in their homes and neighborhoods, and obtain extra income, security, companionship and services; and
E. 
Provide a broader range of accessible and more affordable housing.
(Ord. 20-1379)
An ADU may be located in a detached accessory structure, an attached addition to a primary dwelling, or within a space internal to a primary dwelling, such as a converted basement. A garage may be converted to an ADU provided that the off-street parking requirement for the primary dwelling unit continues to be met. ADUs are permitted subject to the following provisions:
A. 
In the RL zone, one ADU is permitted outright as an accessory use to a permitted single-family dwelling.
B. 
In the RM, RH, NC, and CBC zones, ADUs are permitted as follows:
1. 
One ADU may be permitted outright as an accessory use to a permitted single-family attached or detached dwelling.
2. 
Two ADUs may be permitted on the same lot as a permitted single-family attached or detached dwelling if one ADU is in a detached accessory structure and the other ADU is either internal to the house, or in an addition attached to the house, and the lot has a minimum area of 5,000 square feet. An application for a second ADU on a single lot must be reviewed as an Administrative Action.
3. 
Duplex. One detached ADU is permitted outright as an accessory use to a duplex if the lot has a minimum area of 5,000 square feet. An application for an ADU on a lot with an existing duplex must be reviewed as an Administrative Action.
C. 
In the CG and CLI zones, one ADU is permitted outright as an accessory use to an existing nonconforming single-family dwelling.
D. 
Density. See Section 10.6.170.040(C) for minimum required and maximum allowed density standards for accessory dwelling units.
(Ord. 20-1379; Ord. 23-1395)
In addition to the applicable standards in the zoning district, ADUs must meet the following development standards:
A. 
Drainage, Sanitary Sewer and Water. Adequate provision shall be made for drainage, water and sewage waste.
B. 
City Ordinances. The ADU shall meet all applicable City Ordinances.
C. 
Lot Requirements. The lot requirements (width, depth, area, coverage, etc.) on which the primary dwelling and ADU are located shall be met.
D. 
Front Setbacks. Detached ADUs must be located behind a line established parallel with the front building line of the primary dwelling.
E. 
Rear Setbacks. The minimum rear setback for an ADU may be reduced to 0 feet (zero lot line) if the structure is less than 20 feet in height or the rear lot line abuts an alley.
F. 
Privacy Standards. The following standards are intended to protect the privacy of adjacent properties. Privacy standards are required along wall(s) of a detached ADU, or portions thereof, that are within 20 feet of a side or rear lot line that faces a residential property. A detached ADU meets the privacy standard if either of the following standards is met.
1. 
All windows on a wall are placed in the upper third of the distance between a floor and ceiling. This standard applies to windows on exterior doors.
2. 
Visual screening is provided along the portion of a property line that faces the wall of the ADU, plus an additional 10 linear feet beyond the corner of the wall. The screening shall be opaque; shall be at least 6 feet high; and may consist of a fence, wall, or evergreen shrubs. Newly planted shrubs shall be no less than 5 feet above grade at time of planting, and they shall reach 6 feet high within 1 year. Existing features on the site may be used to comply with this standard.
G. 
Maximum Size. The gross floor area of the ADU shall not exceed 75% of the gross floor area of the primary dwelling (exclusive of garage[s] and unfinished basements) up to a maximum floor area of 800 square feet. All areas being used as living space shall be counted toward the maximum allowance of 800 square feet, whether or not those areas were originally built or intended to be used for habitation. In the case of a duplex, the size of the accessory dwelling unit may be no more than 75% of the living area of the smaller of the 2 primary units or 800 square feet, whichever is less. Two exceptions to this maximum size are permitted:
1. 
Basement ADUs. The total floor area of a basement of the primary dwelling may be used as the ADU, provided the basement area does not exceed the size of the primary dwelling.
2. 
Large Lots. On lots zoned RL that are at least 10,000 square feet and include an existing primary dwelling, the gross floor area of the ADU may be up to 1,000 square feet or 60% of the living area of the primary dwelling, whichever is less.
H. 
Parking. No off-street parking needs to be provided for one ADU on a single lot, so long as the parking requirements for the primary dwelling units are met. A second ADU on a single lot must provide one off-street parking space in addition to the spaces required for the primary dwelling unit. If off-street parking is provided, the parking area shall not be located within any required front and side yard setback, other than existing and/or approved driveways.
I. 
Addressing. The ADU shall be legally addressed with the street address of the primary dwelling plus the designation "Suite B."
(Ord. 19-1373; Ord. 20-1379; Ord. 21-1384)