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Washington · C2b Sub-state (city) facts · 4 min read

ADU, Duplex Conversion, and Off-Street Parking Rules for Landlords in Bellevue, Washington

Direct statutory answer

Landlords in Bellevue must adhere to specific zoning, lease, and parking regulations when converting properties into ADUs or duplexes.

WASHINGTON STATUTORY RECORDMunicipal Zoning Standard ADU, Duplex Conversion, and Off-StreetParking Rules for Landlords in Bellevue, PRIMARY UNITADU SUITESetback & Height RestrictionsBlueprint & Unit Sizing• Size cap: max 25% of multifamily footprint• Minimum dwelling unit dimensions apply• Independent exterior ingress requiredMUNICIPAL BUILDING DEPTPermitting & Safety DivisionCERTIFICATE OF OCCUPANCYCOO REQUIRED PRIOR TO LEASEZoning & Permit Mandate• Formal plans review before conversion• Mandatory pre-occupancy safety walk• Unpermitted rentals face code citationsP1Primary UnitDedicated StallP2ADU TenantOff-Street ReqParking Minimum Rules• Minimum 1 designated off-street space• Street parking cannot satisfy ADU ratio• Paved driveway / carport required

ADU, Duplex Conversion, and Off-Street Parking Rules for Landlords in Bellevue, Washington

Landlords in Bellevue must adhere to specific zoning, lease, and parking regulations when converting properties into ADUs or duplexes. This guide provides a comprehensive overview of the rules and requirements to ensure compliance.

Permitting, Zoning, or Statutory Basis

Bellevue’s zoning laws are governed by the City of Bellevue Code, specifically Chapter 18.02 (Zoning). Under this chapter, landlords must obtain the necessary permits and adhere to specific zoning requirements when converting a residential property into an ADU or duplex. The conversion must also comply with the City’s multifamily district share requirements, which limit the number of ADUs or duplexes that can be converted within a specified area.

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Lease Clauses, Notice Periods, and Timing Requirements

When leasing an ADU or duplex in Bellevue, landlords must include specific clauses in the lease agreement to ensure compliance with zoning and parking regulations. These clauses should address:

  1. Zoning Compliance: The lease must state that the property is being used in compliance with zoning laws.
  2. Parking Requirements: The lease should outline the parking requirements, including off-street parking spaces if applicable.
  3. Notice Periods: The lease should include notice periods for modifications or conversions, allowing tenants sufficient time to adjust to any changes.
  4. Timing Requirements: The lease should specify the timeline for converting the property into an ADU or duplex, ensuring compliance with zoning deadlines.

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Defensible Record-Keeping & Compliance Checklist

To ensure compliance with ADU, duplex conversion, and off-street parking rules in Bellevue, landlords must maintain thorough records of all transactions, permits, and compliance documentation. The following checklist can help landlords stay organized and compliant:

  1. Permits and Approvals: Keep copies of all permits, approvals, and compliance certificates.
  2. Lease Agreements: Maintain a copy of each lease agreement, including any amendments or modifications.
  3. Parking Records: Document all off-street parking spaces and their usage.
  4. Zoning Compliance: Keep records of any zoning violations or compliance issues.
  5. Notice Periods: Document all notice periods sent to tenants regarding modifications or conversions.

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By following these guidelines and maintaining thorough records, landlords in Bellevue can ensure compliance with ADU, duplex conversion, and off-street parking regulations.

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