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

Unincorporated Coos County, Oregon requires a building permit for most new construction, additions, alterations and most repairs¹. The Coos County Building Code applies throughout the unincorporated county and incorporates Oregon specialty codes, including residential, structural, mechanical, plumbing and electrical standards². Coos County issues building permits countywide except structural and mechanical permits inside Coos Bay and North Bend, and Lakeside has its own building department¹. A structural application needs a zoning compliance letter, an onsite septic permit when applicable, building plans, the checklist and the completed application¹. A permit remains valid for 180 days from issuance or the last inspection on progressing work¹. Owner-builders get no permit waiver; Oregon law offers only a narrow exemption from specific structural-code requirements, and a building permit is still issued⁷. Qualifying agricultural buildings may be exempt from the structural specialty code, but electrical, plumbing and mechanical permits still apply, and Planning must first confirm qualifying farm or forest use¹⁰.

Coos County Community Development handles building permits, land-use planning, onsite septic and code enforcement from one office at 60 E Second St., Coquille, OR 97423¹¹. Call 541-396-7770, or email the building desk at building@co.coos.or.us¹¹. The county directs applicants to its ePermitting process, accepts applications electronically, in person or by mail, and offers staff help with account setup¹². Electrical and plumbing requests also need land-use authorization¹². Inside Coos Bay and North Bend, those cities issue structural and mechanical permits, and Lakeside runs its own building department; electrical and plumbing permits elsewhere come from the county¹. Septic permits stay with the county Onsite Septic Program regardless of which office issues the building permit¹.

Coos County's zoning and land-development ordinance covers land outside incorporated city boundaries, so zoning inside a city comes from that city³. The Planning Director enforces zoning, land use and structure location in the unincorporated area¹³. Published districts include Rural Residential RR-2 and RR-5, Controlled Development CD-5 and CD-10, Exclusive Farm Use EFU and Forest F, and overlays can add limits, so confirm the parcel's district on the zone map³. Rural Residential lots generally require 5 acres in RR-5 and 2 acres in RR-2, with exceptions for planned developments and certain older parcels⁶. Urban Residential buildings have a maximum height of 35 feet⁶. A manufactured single-family dwelling is allowed through compliance determination review in the residential, Controlled Development and Rural Center zones, which takes at least 30 days, and is not allowed in the commercial, industrial and recreation zones⁶. Coos County does not publish a general minimum dwelling size in the material we reviewed, and tiny homes are not a defined use; ask Community Development how a proposed unit will be classified.

Oregon DEQ regulates septic-system siting, design, installation, operation and maintenance, while Coos County's Onsite Septic Program provides local permitting, inspections and technical support^4,5. A construction permit is required for new systems and for covered alterations or repairs; an undeveloped site that has never been approved needs a site evaluation¹. Properties without municipal sanitation must install an onsite septic system, although city or sanitation-district requirements may govern where service exists¹. Only about 0.8% of county soils are rated free of severe limits for a conventional drain field, and difficult groundwater, space, slope or soil conditions can require an alternative system^5,14. Call Coos County Onsite Septic at 541-396-7770 for permitting or the inspection-only line at 541-266-1098 when work is ready¹¹.

Coos County allows limited RV stays, not unrestricted full-time occupancy⁶. A guest RV on a lot with a dwelling may stay up to 60 days per calendar year, while an owner or immediate family member may camp up to 45 days per year with no more than 2 RVs under that provision⁶. Oregon also permits occupancy of a camping vehicle on private land only with owner consent, adequate approved water and sewage facilities, and compliance with applicable sanitation and utility standards¹⁵. A private campground in a forest zone is a different conditional use: it is for temporary rather than residential stays and limits the same camper to 30 days in a consecutive six-month period⁶. Urban ADUs cannot be RVs, park models, yurts or similar structures not built for permanent human occupancy⁶. Coos County's general treatment of tiny homes remains unconfirmed; ask Community Development how the proposed unit and occupancy would be classified.

1. Confirm jurisdiction with Coos County Community Development; city limits can change which office issues the permit^1,11.
2. Verify the zoning district, lot-size standard, overlays and whether the proposed use is allowed before design work begins^6,13.
3. Confirm access; new development needs county driveway confirmation before zoning compliance, and state-highway access also needs ODOT approval^16,17.
4. If municipal sanitation is unavailable, obtain the county septic site evaluation and construction permit before finalizing the house location¹.
5. Allow for review time: land-use applications carry a final-action deadline of 120 or 150 days after the application is complete, and a compliance determination costs $330 under the 2026 fee schedule^18,19.
6. Submit the zoning compliance letter, septic permit if applicable, plans, checklist and structural application to Community Development¹.
7. Keep permitted work exposed for required inspections and obtain the certificate of occupancy before moving in²⁰.

Water: a landowner drilling a well needs a $550 permit and a $10,000 bond or letter of credit before work starts unless a licensed, bonded well constructor does the work⁸. Septic: only about 0.8% of county soils are rated free of severe limits for a conventional drain field, so make approval a purchase contingency¹⁴. Zoning: verify the parcel's exact district because RR-5 and RR-2 have different minimum lot sizes, and urban ADUs follow different rules from rural ADUs⁶. Flood: construction in a mapped special flood hazard area needs an approved floodplain application before work begins⁹. Access: county standards set sight-distance and grade requirements, so have the Road Department review a steep or blind approach^16,17. Rental plans: a vacation or short-term rental needs compatibility review, health licensing, compliant access and parking, a recorded deed restriction, and a new compliance determination after ownership changes⁶. Coos County's effective property-tax rate is about 0.7%, with a median annual bill near $2,243¹⁴.