Building permits, zoning and land rules in Clatsop County, Oregon

Yes. An owner or authorized agent must obtain the required permit before constructing, enlarging, altering, repairing, moving or changing the occupancy of a residential building or structure regulated by the Oregon Residential Specialty Code¹. Clatsop County Building Codes administers adopted codes in unincorporated areas and administers electrical codes across both incorporated and unincorporated parts of its jurisdiction¹². In unincorporated Clatsop County, a development permit is required to build a new home, and the Building Codes Division then determines which building permits Oregon law requires⁴. Permit exemptions can apply to particular work, so the safest first question for the Building Codes Division is whether the exact scope needs structural, mechanical, plumbing or electrical approval¹. A qualifying agricultural building may be exempt from the structural code, but the exemption does not cover a dwelling and does not erase electrical, plumbing or mechanical permit requirements¹³. Clatsop County building fees vary by permit type and project valuation, which the Building Official determines, and every county application carries a 3% technology fee on top of the 12% state surcharge, so ask the Building Codes Division for an estimate before you budget^14,15.

The Clatsop County Building Codes Division is the permit office for adopted building codes in unincorporated Clatsop County¹². Reach the division at 503-338-3697 or buildingdivision@clatsopcounty.gov, or visit 800 Exchange Street, Suite 100, Astoria, Oregon 97103⁶. The county directs applicants to Oregon ePermitting to view development and building applications and supporting documents, apply for available permits, and schedule inspections⁶. Land-use applications do not follow that same online path, so contact the Land Use Planning Division at 503-325-8611 or comdev@clatsopcounty.gov before treating a building application as zoning approval^5,6. Inside a city, the relevant city handles its own land-use questions; county planning staff handles potential uses of property in unincorporated Clatsop County⁵.

Yes. Clatsop County Land Use Planning applies the Land and Water Development and Use Code to unincorporated land and reviews development permits, conditional uses, map amendments, variances, partitions, subdivisions, and permits in geologic-hazard and flood-hazard zones². A parcel inside an incorporated city is governed by that city's land-use rules, so county zoning advice should not be carried across a city boundary¹⁶. Setbacks are not countywide constants: in the reviewed residential district, front yards vary with road classification, side and rear yards vary with lot or housing type, and all structures have a specific aquatic-area setback¹⁷. Dividing land outside city limits or urban growth boundaries into three or more new parcels requires a subdivision request and compliance with zoning, parcel-size, access, hazard and sanitation standards¹⁰. The county's Web Maps show zoning for properties outside urban growth boundaries and city limits, and its Zoning Guide lists setbacks and permitted uses by district¹⁸. District lot sizes differ widely: in the Rural Service Area-Multi-Family Residential zone, a detached dwelling needs 5,000 square feet with state-approved sewer and 15,000 square feet without it¹⁷. Ask Land Use Planning to identify the parcel's district before relying on a setback or division plan⁵.

Clatsop County's Onsite Septic Program issues permits for households that are not served by public sewer³. A parcel relying on onsite sanitation must be large enough to meet Oregon DEQ requirements for a septic tank and drain field or another approved system and to continue using that disposal method¹⁹. For a new home system with projected flow below 2,500 gallons per day, obtain a favorable site evaluation before applying for the construction-installation permit; the issued permit is valid for one year²⁰. A pre-cover inspection is required unless the local onsite agent waives it, and the system may be covered only after a satisfactory inspection²⁰. Only about 0.8% of county land is rated without severe limitations for a conventional drain field, so soil, water-table, surface-water and well conditions can materially affect feasibility and budget^19,21. Septic permits are separate from development and building permits and come from the county's septic program³. Reach Clatsop County Onsite Septic at (503) 338-3687 or septic@clatsopcounty.gov⁷.

Do not assume that owning rural land creates an unrestricted right to occupy an RV. Oregon allows temporary occupancy of a camping vehicle on private land only with the owner's consent, adequate space for approved water and sewage facilities, and compliance with applicable sanitation, plumbing, electrical and sewer rules⁸. In a county-regulated recreation vehicle park, permanent occupancy is prohibited and an RV may remain no more than 30 days in any 60-day period⁹. The park rule does not establish the limits for an ordinary private parcel, so ask Land Use Planning about the parcel, zoning district and proposed duration⁵. Clatsop County has no separate tiny-home category that we could confirm, so a tiny home is treated like any new home: it needs a county development permit, a use permitted in the zoning district, and documentation of water, septic feasibility and legal access¹⁰. A dwelling of 400 square feet or less must also meet the state Small Home Specialty Code¹. We could not confirm a countywide minimum dwelling floor area. Manufactured dwellings are allowed only where the applicable zoning and placement standards permit them, with water, sewage, electrical, setback, space and access requirements⁹.

1. Ask Land Use Planning to confirm the parcel's jurisdiction, zoning, allowed dwelling type, district-specific setbacks and any geologic- or flood-hazard review^5,17. Apply for the county development permit, which comes before building plan review⁴.

1. If the project includes a land division, resolve subdivision review, parcel size, access, hazards and sanitation before designing the home¹⁰.

1. Determine water and wastewater service early; where public sewer is unavailable, obtain the county septic site evaluation before applying for a new-system construction permit^19,20.

1. Apply for a county approach-road permit before building or altering a driveway onto a public or county road, and a floodplain development permit before any work if the property is in the 100-year Special Flood Hazard Area^22,23.

1. If a landowner will construct a well, secure the required state landowner permit, fee and financial security before work unless a licensed and bonded Water Supply Well Constructor performs it¹¹.

1. Submit the required building application before regulated residential work begins, then complete required building and septic inspections before covering work or occupying the home^1,6,20.

Confirm the boundary between unincorporated county land and a city first, because Clatsop County administers rural zoning while each city answers for property within its limits¹⁶. Ask Land Use Planning for the zoning district, allowed dwelling type, setbacks, access constraints and any geologic- or flood-hazard review tied to the parcel⁵. Treat wastewater feasibility as a purchase condition: only about 0.8% of county land is rated without severe limitations for a conventional septic drain field²¹. The county receives about 88.8 inches of precipitation annually, only about 17.5% of its land has a slope of 15% or less, and about 86.8% is wooded, which makes drainage, slope and clearing questions especially practical²¹. We could not confirm a countywide rule requiring every parcel to connect to a public or private water or sewer utility, so ask planning and the relevant service provider about the specific address⁵.