Oregon, Multnomah County Remodeler Permit Regulations and County Ordinances for Unincorporated Areas

Oregon Remodeler and Renovation Permit Requirements for Multnomah County

Multnomah County's Building and Safety Division acts as the Authority Having Jurisdiction (AHJ) for building permits in unincorporated areas of the county. For properties within incorporated cities like Portland, the respective city's building department is the AHJ.

Unincorporated Areas

In unincorporated Multnomah County, all construction, alteration, repair, demolition, and change of occupancy require permits. This ensures work complies with the Oregon Structural Specialty Code (OSSC), Oregon Residential Specialty Code (ORSC), and other applicable local amendments and regulations. Homeowners and contractors are responsible for obtaining the necessary permits before starting work.

Demolition Work

Demolition work during a remodel in unincorporated Multnomah County generally requires a permit. This is especially true for the demolition of structural elements, load-bearing walls, or any work that affects the structural integrity of the building. Even partial demolition may trigger permit requirements depending on the scope and potential impact on safety and code compliance. It is advisable to consult with the Building and Safety Division to determine specific triggers for demolition permits.

Converting Non-Living Spaces

Converting non-living spaces such as garages, attics, or unfinished basements into habitable living areas in unincorporated Multnomah County requires a building permit. This process is considered a significant alteration and involves ensuring the space meets all current building code requirements for habitable rooms. Key areas of focus include:

Egress: Adequate emergency escape and rescue openings (windows) are mandatory.
Ventilation and Light: Sufficient natural or mechanical ventilation and light must be provided.
Insulation: Compliance with energy code requirements for insulation in walls, floors, and ceilings.
Fire Safety: Installation of smoke detectors and carbon monoxide alarms.
Structural Integrity: Ensuring the existing structure can support the intended use and any new loads.
Plumbing and Electrical: Any new plumbing or electrical work must meet code standards and be permitted.

The definition of "habitable space" typically includes areas designed for sleeping, living, or cooking. Unfinished basements, attics, and garages are generally not considered habitable until they are brought up to code through a permitted renovation process.

Resources to Learn More

Note: The following state-wide building codes and regulations apply universally to all jurisdictions within Oregon, including Multnomah County.

Oregon Remodeler Legislation, Codes, and Guidelines

Oregon Building Codes for Remodelers and Residential Renovations

In Oregon, the Department of Consumer and Business Services (DCBS), through its Building Codes Division, is responsible for adopting, administering, and enforcing a uniform, statewide building code. This code governs construction and ensures minimum safety standards across the state. Many cities and counties administer and enforce these codes locally.

The state building code is comprised of various specialty codes. For existing buildings and renovations, the primary code is the 2021 Oregon Existing Building Code, which is based on the 2018 International Existing Building Code (IEBC) with Oregon-specific amendments. Other relevant codes include the Oregon Residential Specialty Code (ORSC) and the Oregon Structural Specialty Code (OSSC).

Generally, permits and plan review are required for remodels that involve structural changes, the creation of habitable space, alterations to openings, or modifications to electrical, plumbing, or mechanical systems. Cosmetic work, such as painting, replacing cabinets, or installing new flooring, is typically exempt from permits, provided it does not affect the structure or systems. However, even exempt work must comply with local zoning and code requirements.

Converting attics or basements into habitable living spaces is considered a structural alteration and will require permits and inspections.

Demolition guidelines vary by locality, but generally involve specific notification periods for property owners and may require deconstruction for older structures. For instance, some local ordinances may require a 15-day notice before demolition begins and specify procedures for debris removal and site restoration.

Recent legislative changes in 2024 and 2025 aim to streamline permitting processes for renovations. For example, municipalities over 15,000 in population may be prohibited from requiring frontage improvements as a condition for altering existing buildings, provided certain criteria are met regarding square footage, alteration cost, and occupancy classification.

Resources to Learn More

Select a City in Multnomah County

If your project is located within incorporated city limits, you will likely need to follow municipal ordinances rather than county rules. Select your city below to view local regulations.

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