Washington County, OR Fence Regulations: Fence Permit Requirements (2026)
Key Facts
- Fence permit trigger
- Over 7 feet in height
- Retaining wall permit trigger
- Over 4 feet in height
- Wall height measured
- From bottom of footing to top
- Setback exemption
- Compliant fences/walls need no setback
- Combo structure exemption
- Only if backfill is level
Summary
A building permit is required in unincorporated Washington County for any fence over 7 feet tall, and for any retaining wall over 4 feet, under Section 419-3. Fences and retaining walls at or below those heights can go up without a building permit, though other yard and setback rules still apply.
Any fence over 7 feet in height requires a building permit. Any retaining wall over 4 feet in height requires a building permit (the height measurement of a retaining wall is from the bottom of footing to the top of the retaining wall).
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: Community Development Code: Supplement 2 | Code of Ordinances: Supplement 25).
Full Breakdown
Section 419-3 of the Community Development Code sets the permit trigger directly beneath its height limits: any fence over 7 feet in height requires a building permit, and any retaining wall over 4 feet in height requires a building permit, with the wall's height measured from the bottom of the footing to the top. Because the standard fence height cap is itself 7 feet under the same section, most residential fences never need a permit at all; the permit requirement only kicks in for a taller fence, most commonly one built to the 8-foot arterial/highway allowance, or for a retaining wall taller than 4 feet measured from the footing.
2. A combination fence-and-retaining-wall structure under Section 419-4 is treated differently: it is exempt from a structural building permit only when the backfill is level for a proportional horizontal distance to the wall's height, or as the Building Official otherwise approves.
Violations & Fines
Building a fence over 7 feet or a retaining wall over 4 feet without first obtaining a building permit violates Section 419-3 and Section 215-1's prohibition on developing land contrary to the Code. Washington County Building Services can red-tag the unpermitted structure, and the Director may deny or condition other permits on the property under Section 215-2 until it is resolved or removed.
Frequently Asked Questions
Do I need a permit to build a 6-foot backyard fence in unincorporated Washington County?
What about a retaining wall in my side yard?
Can I combine a fence and retaining wall to get more height without a permit?
Sources & Official References
Other rules in Washington County
Compare Washington County to another location·View the Oregon fence regulations overview
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