Key Standards for D-ADUs*

*Refer to BCC 11.340.050 and underlying residential zone for all standards  

  • A D-ADU shall comply with the same setbacks for an accessory building in the zoning district in which the lot or parcel is located.  Regardless of size, a D-ADU cannot be created within a building or structure which has utilized the reduced side and rear setbacks allowed for small accessory buildings or structures found in BCC 11.160.260.  All structures shall also comply with the maximum lot coverage percentages for the zone in which it resides. 
  • The height of a D-ADU shall conform to the height limit specified for accessory buildings in the zoning district in which it is located.
  • Balconies on a D-ADU shall be located on the interior side of the lot and building, not adjacent to a rear or side yard shared with a neighboring residence, and:
    • Shall not exceed 80 square feet in size when located above the ground level of the building;
    • Shall be located a minimum of 20 feet from a side or rear yard lot line unless the applicable side or rear yard lot line is adjacent to an alley;
    • Rooftop decks or second-story decks are prohibited on an accessory structure used as a D-ADU.
  • Two off-street parking spaces required (not including 2 spaces for main dwelling), as shown in diagram – Refer to 11.340.040 

 Permissible ADU Parking Areas (PNG)

  • A D-ADU shall comply with all building construction and fire codes in effect at the time the D-ADU is constructed, created, or subsequently remodeled, including obtaining the required building and other permits.
  • D-ADUs shall be a permanent structure anchored to a foundation which meets the adopted building codes. Trailers, mobile homes, tiny homes with wheels, and other portable or temporary structures, or structures with wheels shall not be permitted as a D-ADU.
  • Entrance Locations. The entrance to a D-ADU shall be located:
    • Facing an alley, public street, rear or side façade of the primary dwelling, or rear yard of the single-family dwelling on the same property.
    • Facing a side or rear property line provided the entrance is located a minimum of 10 feet from the side or rear property line if at ground level or first story level or 20 feet from side or rear property line if above the first story.
    • Exterior stairs leading to an entrance shall be located a minimum of 20 feet from a side or rear property line.
  • Exterior stairways and landings shall not encroach within 20 feet of an adjacent property containing a single-family or townhome residence.


Show All Answers

1. What is an Accessory Dwelling Unit (ADU)?
2. Where are ADUs allowed?
3. How many ADUs are allowed on a property?
4. What are the benefits of getting an ADU permit?
5. Where can I find an ADU application?
6. How to apply for an ADU?
7. What are the code requirements for having an ADU?
8. Does having an ADU mean I can have a short-term rental or AirBnb?
9. Types of ADUs
10. Key Standards for all ADUs*
11. Key Standards for D-ADUs*
12. Standards for I-ADUs*