Secondary Dwellings

About the Dwellings
A secondary dwelling, also commonly referred to as a granny flat, may be added to residential zoned properties to provide an additional living unit along with a primary home. The addition of the secondary unit must comply with zoning regulations that will determine allowable size, location, and design.

The exterior of secondary units must be compatible in appearance with the primary home. Exterior materials shall be high-quality wood, stucco, stone, or masonry.

Window Placement
  • A secondary unit that is 15 feet or less from a residential unit on an adjacent parcel shall not have windows that directly face windows on the other unit.
  • A detached secondary unit located closer than 10 feet to a side lot line or 20 feet from a rear lot line shall have no 2nd floor windows facing the side or rear except for obscure glass.
The placement of the secondary unit must comply with the same setbacks that apply to the primary home. The setbacks are determined by the zoning district for the parcel, except that a 2-story unit shall provide side and rear setbacks that are 3 feet more than required by the applicable zoning district. Refer the the Development Standards page for setbacks by zoning district. If you do not know the zoning designation for your property, you may complete an online Zoning Information Request Form.

Height Limit
Secondary units may be no higher than 20 feet unless the secondary unit is above a garage. If it above the garage, the maximum height is 25 feet.

Size Limitations & Requirements
The total square footage of a secondary unit is limited to no more than 60% of the square footage of the primary home with a maximum allowance of 1,200 square feet. For example, if a primary home is 1,800 square feet, including attached garage space, the second unit may be no more than 1,080 square feet (60% of 1,800 square feet).

Secondary Units With Attached Garage
If the secondary unit has its own attached garage, you may exempt no more than 400 square feet of the garage space in the calculation. There may be no internal doorways from the living unit to the attached garage.

Maximum Site Coverage
The maximum site coverage of all residential accessory structures on a parcel must comply with the following cumulative footprint of the accessory structures:
 Lot Area (In Square Feet)
 Maximum Cumulative Footprint of all Accessory Structures (In Square Feet)
 Less Than 10,000
 10,000 - 20,000
 More Than 20,000
* More square footage may be approved through a Minor Use Permit.

Accessory Structure Examples
This total includes all accessory structures on the property such as the:
  • Additional living unit
  • Detached carports
  • Detached garages
  • Detached storage units
Conversion of Existing Building
An existing building may be converted to living space if the existing building conforms to zoning requirements. It should also be noted that commonly when a garage or barn is constructed, they are built for storage not for living space so building improvements will probably be required.

On-site parking must be provided for the secondary unit as well as the required 2 parking spaces for the primary home. 1 off-street parking space must be provided for each bedroom in the secondary unit with a maximum of 2 spaces. These spaces are not required to be covered but must have an approved driveway surface and meet the minimum driveway standards.

Other Requirements
  • Secondary units may not be offered for sale apart from the principal unit.
  • Secondary units may have no more than 2 bedrooms.
  • Maximum height of a secondary unit is 20 feet except when the secondary unit is above a garage in which case it shall not exceed 25 feet.
  • Secondary units can be rented to anyone. The occupants do not have to be related to the owners of the property and do not have to be over a certain age. Also, it not required that the owners of the primary home live on the property.
  • Your project will be reviewed to make sure that the design and placement of the secondary unit works well with the primary home and fits well into the surrounding neighborhood.
  • Secondary units may be attached to the primary home providing the secondary unit has a separate entrance.
  • The design and appearance of the secondary unit shall be complimentary to the primary dwelling.
  • Windows of second units shall not face the window of a neighboring home if that home is closer than 15 feet.
  • 2-story units shall have obscure glass on the side and rear windows if secondary unit is closer than 10 feet to the side property line or 20 feet from the rear property line.
  • All secondary dwelling units require a Building Permit and must comply with applicable building, fire, health and safety codes, as well with zoning requirements.
How to Apply
Plans will need to be submitted in order to obtain a Building Permit. Pick up an application package from the Building and Safety Division for a list of plans and information that is required for your project.

Additional Information
This information is provided as a courtesy and identifies requirements for residential secondary dwellings. Additional information may be found within the Zoning Code Section 106.42.210 (PDF). Any discrepancy between this information and the Zoning Code shall control. For additional information, contact the Planning Division at 916-727-4740.