Spokane Municipal Code §17C.300.100 permits attached and detached ADUs in the RA through RHD zones, including planned unit developments, subject to the code’s conditions. The current code section was amended by Ordinance C36696, effective July 11, 2025.
Check the zone and unit count
The code allows two ADUs per lot in the RA, R1, R2, RMF, and RHD zones, subject to the underlying district’s development standards. Check the parcel’s exact zone and any planned unit development conditions rather than assuming that the citywide label settles the result.
Decide whether the additional unit is an ADU or principal dwelling
Where a proposed unit meets the criteria for both an ADU and an additional principal dwelling, the code allows the applicant to choose which classification to use. The City gives examples such as a second unit of a duplex or a second single-unit residential building on a lot. This choice can change which rules to apply, so identify the intended route before relying on the ADU count.
Use the current consolidated code and confirm the parcel, zone, PUD standards, and project details with Spokane. A two-unit allowance is not a finding that two ADUs can physically or legally be built on every qualifying lot.