ADU Code Amendments at a Glance



In 2007 the City first adopted zoning code language that allowed ADU’s within the city. Since that time city staff has become aware of some of the issues relating to the existing ADU code, including a restriction on homeowners and builders building an ADU above a garage. The primary reason for bringing forward the proposed code changes is to allow ADU’s above garages.  


An ADU & Infill Housing Committee was formed and workshops were held together with the Planning Department staff to discuss possible code changes regarding ADU’s. A joint workshop was also conducted with the Planning Commission to work on the proposed ADU code amendments. The following is a list of the history and prior workshops that were held:


      • January 2019              - Goal set to amend ADU Cod
      •                                   - ADU & Infill Housing Committee formed
      • February 22, 2019        - 1st   Workshop
      • March 15, 2019             - 2nd Workshop
      • April 26, 2019               - 3rd Workshop
      • May 28, 2019                - 4th Joint Workshop With Planning Commission

PUBLIC HEARING was held by Planning Commission on Tuesday, July 9, 2019, 5:30 PM and the following ADU amendments were recommended to be approved by City Council

City Council approved the ADU Code Amendments on August 20, 2019 with an effective date of Monday, August 26, 2019.

Please CLICK HERE to see the approved ADU Code Amendments.


The purpose of the proposed ADU Code amendments is to primarily address the code issue of the height restriction that did not allow for accessory dwelling units above garages in the rear yard. The ADU & Infill Housing Committee and City Staff also agreed that there should be a side and rear yard “Second Story Step Back” for detached ADU’s in order to provide air space and light between properties.

The proposed ADU code amendments addresses these issues along with others items, such as Lot Coverage, size of ADU, Design Standards, allowing existing garages to be converted to an ADU, and side and rear setback requirements.   Below is a list of the items that were discussed at the recent workshops. The full proposed ADU code amendments are attached at the end of this staff report.

The purpose of these revisions to the Zoning Code is to ensure health, safely, and welfare of the public and property owners in the City of Coeur d’Alene, while protecting property rights.


Proposed Zoning Code Amendments at a glance:


  • ADU Unit Size: Proposed Code Changes
        • No Minimum unit size.
        • Maximum up to 800 SF (finished square footage; doesn’t include unfinished basements).
        • ADU shall not exceed 75% of the total square footage of the primary dwelling unit.
  • Building Height of Detached ADU: Proposed Code Changes
        • Maximum Height 24’ for unit above garage (the roof slope requirements would be removed for new detached ADUs, but two story ADUs must meet second story step back).
        • Maximum Height 18’ for one story unit.
        • Allowable projections per existing code for such things as chimneys, antennas, etc.
        • Railings and parapets cannot exceed maximum height.
  • Owner Occupancy Requirement: Proposed Code Changes
        • Not required, unless the property has a Short Term Rental (STR).
        • If property is used for Short Term Rental (STR) then one unit must be owner occupied.
        • Affidavit would still be required for all ADU’s to acknowledge ADU status of property and compliance with code. City Code will be amended to address owner occupancy requirement for Short Term Rentals.
      1. Parking Space Size: No Change
        • Parking space size remains 9’ x 20’
      1. Design Standards: Proposed Code Changes
        • Not a requirement for new detached ADU’s.
        • Additions to an existing structure or newly constructed detached structures created for the purpose of developing an accessory dwelling unit, shall be designed consistent with the existing roof pitch, siding, and windows of the principle dwelling unit.
  • Existing garages and sheds: Proposed Code Changes
        • Allow existing garages and sheds would be allowed to be converted to an ADU provided that the structure can meet the current adopted building codes and that it is not over the property line or in the City’s right-of-way.
        • The structure could not be expanded outward or upward without triggering the Non-Conforming Code and requiring the structure to meet the current standards.
        • Existing 25’ tall garages could be converted to an ADU without having to meet the 24’ maximum height or the second story step back requirements, but they would need to meet Building Code and ADU parking requirement, affidavit, etc.
      1. Setbacks of Detached ADU: Proposed Code Changes
        • SIDE: Minimum Five foot side yard setback required.
        • All ADU’s shall be set back from the side lot line at least five feet (5'). Remove the language from the code that allows ADU’s to be three feet (3’) from the property line.  “However, an accessory structure may be set back three feet (3') from the side property line provided the roof does not slope toward the side property line.”
        • REAR with Alley: Minimum 3’
        • REAR No Alley : Minimum 5’  
  • Step Back of second story of Detached ADU from property lines: Proposed Code Changes
        • The group agreed that there should be some sideyard Step Back for the second story of detached ADU’s in order to provide air space and light between properties. NOTE: This is being required to remove the concern of the previously repealed code that allowed 25’ tall accessory structures that negatively impacted neighboring properties.
        • The upper step back would begin at 10’ height on the interior side property line and at 15’ height on the rear yard property line (see exhibit).
        • The step back would be 1:1 measurement, which equates to a 45 degree angle.
        • There would not be a second story step back requirement on the street side of a corner lot.
        • Eaves can project 2 feet into the step back air space.
        • Building permit submittals would need to show all dimensions, setbacks and step backs.
        1. Lot Coverage/Open Space & Pervious Surface Requirement - Proposed Code Changes
              • A 30% Pervious surface will be required for all lots with an ADU.
              • Pervious surfaces include such things as grass, AstroTurf, pavers, grasscrete, gravel, and decking materials (unless it has a concrete or impervious surface below it).
              • There will not be a dimensional requirement or a requirement for a certain type or quantity of landscaping/trees (other than the standard street tree requirements).
              • The permit submittal will need to show all pervious areas on the lot and calculations.        
              • Proposed ADU Code Amendments




If you have any questions, please contact Mike Behary (Planner) at [email protected] or by calling (208) 769-2271.