Spokane ADU Permit Process - City Regulations

Housing and Building Standards Washington 3 Minutes Read · published February 10, 2026 Flag of Washington

Spokane homeowners considering an accessory dwelling unit (ADU) must follow city zoning and building permit rules in Spokane, Washington to convert or add a separate dwelling on their property. Start by reviewing the City of Spokane ADU guidance and local standards to confirm eligibility, allowable size, parking and owner-occupancy rules before preparing plans and permit paperwork.[1] This article explains the permit steps, inspections, enforcement pathways, common violations, appeals, and practical action steps to get an ADU permitted and occupied legally.

What an ADU is and when permits are required

An accessory dwelling unit (ADU) is a secondary housing unit on the same lot as a primary residence, which may be attached or detached depending on zoning. A building permit is required for most new ADUs, conversions, and significant remodels that change means of egress, plumbing, or electrical systems.

Permits, reviews, and timelines

  • Pre-application: confirm zoning and lot standards, then schedule a pre-application or planning intake if recommended.
  • Building permit: submit plans, site plan, and required forms to Building Services; structural, plumbing, mechanical, and electrical permits may be needed.
  • Review time: variable depending on completeness and scope; plan for multiple review cycles.
  • Inspections: schedule required inspections during construction and obtain final approval before occupancy.
Begin by confirming zoning allowances for ADUs on your lot before paying for drawings.

Penalties & Enforcement

Enforcement is handled by city code enforcement and building officials. Where work is completed without required permits or where an ADU violates zoning or safety codes, the city may require permits be obtained retroactively, order corrections, or take enforcement action.

  • Fine amounts: not specified on the cited page.[3]
  • Escalation: first, repeat, and continuing offence procedures are not specified on the cited page.
  • Non-monetary sanctions: stop-work orders, mandatory corrective work, denial of occupancy, and court enforcement actions are tools the city uses.
  • Enforcer and complaints: Code Enforcement and Building Services receive complaints and investigate; use the city's code enforcement contact/complaint page to report violations.[3]
  • Appeals and review: appeal routes typically follow administrative appeal procedures established by the city; specific appeal time limits are not specified on the cited pages.

Applications & Forms

The primary permit application and submittal instructions are managed by City of Spokane Building Services. Specific form names and fee schedules are published on the building permits page; if a specific form number or fee is required, follow the instructions on that official permit page when applying.[2]

Common violations

  • Constructing an ADU without a building permit.
  • Failing to meet required setbacks, lot coverage, or parking conditions.
  • Inadequate egress, unsafe electrical or plumbing work, or missing inspections.
Unpermitted ADUs can result in stop-work orders and denial of legal occupancy.

Action steps for homeowners

  • Step 1: Confirm your property zoning and whether ADUs are allowed in your zone.
  • Step 2: Prepare site plan and construction drawings; consider a pre-application meeting with Planning or Building Services.
  • Step 3: Submit building permit application with required documents and pay applicable fees via the Building Services permit portal.[2]
  • Step 4: Schedule inspections during construction and obtain final inspection and certificate of occupancy before renting or occupying the ADU.
  • Step 5: If you receive an enforcement notice, follow the correction timeline or file an appeal per city instructions; contact Code Enforcement for guidance.[3]

FAQ

Do I always need a building permit for an ADU?
Yes — most new ADUs and conversions that alter structure, plumbing, electrical, or egress require building permits; check Building Services for the full submittal requirements.[2]
What size and parking rules apply to ADUs in Spokane?
Specific size limits, parking requirements, and owner-occupancy rules are governed by Spokane zoning and ADU standards; see the City ADU guidance for standards and examples.[1]
How long does permitting take?
Review times vary based on application completeness and scope; expect multiple review cycles and plan for variable timelines as noted by Building Services.

How-To

  1. Confirm zoning: verify your lot's zoning and ADU allowances with Planning.
  2. Gather documents: prepare site plan, floor plans, and technical drawings.
  3. Submit permit: apply through Building Services with required forms and fees.[2]
  4. Build and inspect: schedule inspections at each required stage.
  5. Obtain final approval: receive final inspection and certificate of occupancy before use.

Key Takeaways

  • Always check Spokane zoning and Building Services requirements before planning an ADU.
  • Permits, inspections, and final approval are required to legally occupy an ADU.

Help and Support / Resources

  1. [1] City of Spokane - Accessory Dwelling Units project page
  2. [2] City of Spokane - Building Permits and submittal instructions
  3. [3] City of Spokane - Code Enforcement and complaint reporting

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