Building permits, zoning and septic rules across Oregon’s counties

Oregon has a statewide building code, including a residential specialty code for houses and townhouses^1,10. The county figures below concern unincorporated land; project-specific building permits, zoning and land-use allowances must be checked with the local jurisdiction^2,11.

Residential building permits are listed as required in 34 counties and limited in 1, Yamhill County². We could not confirm the no-permit classification for Washington County; ask the local building department before relying on that exception^3,11. Use the Oregon no-building-codes comparison as a starting point, then confirm the parcel’s building-permit requirements³.

Oregon’s owner-builder exemption covers ceiling heights, room sizes and specified temperature requirements, but still requires a building permit; it is not a general permission to build without inspections or codes⁷. The owner-builder county list helps narrow the search, while eligibility follows the state’s conditions⁷.

None of Oregon’s 36 counties is listed as having no countywide zoning, and no county is listed as having neither zoning nor residential building permits². Oregon’s statewide zoning map represents local zoning; local governments remain the authorities for parcel-level determinations and ordinance administration¹².

Resource-land zoning can change the land-buying calculation: the statutory minimum parcel sizes are generally 80 acres for exclusive farm use land that is not rangeland, 160 acres for exclusive farm use rangeland and 80 acres for designated forestland, subject to statutory exceptions and qualifying smaller county standards¹³. Those resource-zone standards are not a statewide minimum for every residential lot¹³. Ask the local planning office about the parcel’s district and proposed dwelling before treating acreage alone as an answer¹².

The Oregon Department of Environmental Quality directly issues residential and small-business septic permits in Curry, Jackson and Josephine counties through its Medford office; DEQ contracts with local jurisdictions in the other 33 counties⁴. DEQ’s residential septic page links to the local permitting-authority contacts, so start there rather than assuming the building department also handles septic¹⁴.

An undeveloped site that has never received septic approval needs a site evaluation, and new septic construction requires a construction permit; alterations and repairs also fall under septic permitting¹⁵. DEQ requires an affirmative Land Use Compatibility Statement before issuing a construction permit for new construction or alterations¹⁵.

A composting toilet does not remove the need for an approved wastewater treatment system for household water, and a building within a sewer district still needs a sewer connection¹⁶. Plan the wastewater solution alongside zoning approval, rather than treating off-grid sanitation as an automatic exemption^15,16.

Oregon has county-level RV answers for 24 counties: 2 allow qualifying uses, 2 allow only temporary occupancy, 17 have limited uses and 3 prohibit the covered use; the remaining 12 have no confirmed county-level answer⁵. Umatilla County allows an RV dwelling option in its Mountain Residential zone with zoning approval, while Lincoln County allows qualifying RV uses under applicable conditional-use provisions⁵. Compare the RV-living county list, paying attention to each use’s conditions⁵.

Oregon’s rural RV rental law applies when a county elects to allow the use on qualifying property with an existing owner-occupied primary dwelling; it does not generally authorize an RV home on an empty rural parcel¹³.

Tiny-home answers cover 13 counties: 2 allowed, 9 limited and 2 prohibited; 23 remain unconfirmed⁶. Klamath County allows code-compliant small dwellings, and Curry County allows qualifying manufactured tiny homes on permanent foundations⁶. The tiny-home county list distinguishes these uses from homes on wheels⁶.

Union County leads the Bolthole Index at 71, followed by Umatilla County at 68, Jefferson County and Polk County at 65, Benton County, Klamath County and Morrow County at 63, and Baker County at 62; all of these counties require residential building permits and have zoning². A high score therefore does not mean permission to build or occupy an RV without local approval^2,5.

The median county farmland value is $4,773 per acre, with Harney County at $1,268 and Grant County at $1,324; these are farmland values, not asking prices for ready-to-build lots². Oregon’s median county effective property-tax rate is 0.8%, and the median county property-tax bill is $2,520 annually; neither figure is a quote for a particular parcel².

Oregon’s domestic groundwater-use exemption covers use up to 15,000 gallons per day, but the exemption can be limited in a Critical Groundwater Area; 17 counties overlap a special groundwater management regime⁸. An exempt water use is a different question from permission to construct a well: an owner doing well work without being a licensed and bonded well constructor needs a landowner well permit before starting⁹.

The landowner permit fee is $550, and the required bond or irrevocable letter of credit is $10,000⁹. Oregon Water Resources Department’s Well Construction and Compliance program oversees well standards and keeps well reports; ask that office about the proposed well and the local watermaster about the water source¹⁷.

For a new driveway onto an Oregon state highway, or a change in use of an existing connection, written ODOT permission is required through the highway approach permit process¹⁸. There is no application-submission fee, but design, construction, insurance, bond and other associated costs may apply¹⁸.