Kootenai County to revise Bolton 77 ADU policy to comply with House Bill 583; commissioners debate duplex risk and enforcement

Kootenai County staff reopened discussion of a longstanding local policy known as 'Bolton 77' that governs attached additional dwelling units (ADUs). Staff said House Bill 583, effective July 1, removed the county's ability to limit rentals in certain ADU contexts and required the county to adjust local policy.

The proposed edits would strike the county rental limitation prohibited by the state law, remove a shared HVAC/meter requirement staff described as difficult to enforce, and change the size standard for secondary attached units to either 1,000 square feet or 50% of the primary dwelling's habitable area (the board debated whether the lesser or greater should control). Staff noted the policy was intended to provide an option for property owners—particularly over the aquifer—who cannot build a duplex.

Commissioners raised concerns that removing the 1,000-square-foot cap (or the alternative drafting choices) could make the attached unit effectively a duplex in practice. Staff responded that bedroom counts and septic capacity (reviewed by the health district) and shared-utility requirements are part of how ADUs are distinguished from duplexes. Commissioners also emphasized property-rights considerations and asked staff to bring the edited policy back for formal action.

At the end of the discussion staff was directed to schedule Bolton 77 for action at the next business meeting.