Shed Permit in Portland, OR
Permit Summary
Do You Need a Shed Permit?
Exemptions
Under the currently effective 2023 Oregon Residential Specialty Code, a nonhabitable one-story detached accessory structure does not require a building permit when its building area is 200 square feet or less and its height is 15 feet or less. On a parcel of 2.0 acres or greater, the exempt building area may be up to 400 square feet if the structure is at least 20 feet from all property lines and regulated structures. The exemption does not waive zoning, code, floodplain, or trade-permit requirements. Habitable or attached sheds do not qualify for this detached-shed building-permit exemption.
Attached Shed Rules
Portland lists a shed or other enclosed structure attached to a house as an addition that requires a building permit. The small accessory-structure exemption in ORSC R105.2 applies to detached structures, so an attached shed does not qualify for that exemption.
Shed Use Rules
Habitable structures require a building permit regardless of size. Portland allows a heated detached accessory structure within the R105.2 size and height limits to remain exempt from a structural building permit only if it has no kitchen, is not used for overnight sleeping, and is not used for a business, including licensed child care or a home-based business operating under a Home Occupation Permit. Applicable trade permits and zoning rules still apply.
Zoning & Placement Rules
Zoning Rules
All development must comply with Portland Title 33 whether or not a building permit is required. For a small detached shed below the building-permit threshold, a separate zoning permit is generally optional unless a land-use approval condition, plan district, overlay zone, or other zoning requirement makes it mandatory. In single-dwelling zones, detached accessory structures are allowed only in conjunction with a primary building, and applicable floor-area, building-coverage, setback, height, outdoor-area, and other zone standards still apply.
Setback Rules
Detached and connected covered accessory structures are generally subject to the required building setbacks of the base zone. In the R7, R5, and R2.5 zones, a detached covered accessory structure may be placed in required side and rear building setbacks only when all standards in PCC 33.110.245.C.2.b are met, including being at least 40 feet from a front lot line and, on a corner lot, at least 20 feet from a side-street lot line; a footprint no larger than 24 by 24 feet; limits on combined length along a property line; a maximum 15-foot structure height and 10-foot wall height in the setback; screening; no doors or windows in setback walls facing an adjacent lot line; no rooftop deck; and dormers at least 5 feet from applicable side and rear lot lines.
Maximum Height Rules
In Portland's single-dwelling zones, the maximum height for detached and connected covered accessory structures is 20 feet. Structures more than 15 feet high are subject to additional zoning design standards. The 15-foot level is also the height limit for the detached nonhabitable shed building-permit exemption.
Lot Coverage Rules
In single-dwelling zones, the combined building coverage of all detached and connected covered accessory structures may not exceed 20% of the total site area. The building coverage of each such accessory structure may not exceed the building coverage of the smallest primary structure or 900 square feet, whichever is greater. Overall base-zone building-coverage and floor-area limits also apply, including to sheds that are exempt from a building permit.
Special Area Rules
Additional requirements can apply in environmental overlay zones, plan districts, historic or design-review contexts, flood hazard areas, and other special site conditions; a zoning permit may be required even when the shed is exempt from a building permit. A site slope over 20% requires a geotechnical engineering report for a building-permit application. New construction and substantial improvements in flood hazard areas must satisfy applicable flood-damage-minimization requirements even when the work is otherwise exempt from a building permit.
Construction Requirements
Foundation Rules
Portland does not prescribe one foundation type for all sheds on its project page. For a permitted shed, the construction documents must show typical foundation construction and a foundation plan showing how new loads are supported, including ventilation, underfloor access, and hold-downs where applicable. The foundation and structural design must comply with the applicable residential building code.
Fire Separation Rules
For sheds that require a building permit, the current ORSC generally requires fire-resistance-rated exterior walls when the fire-separation distance is less than 3 feet and restricts projections near property lines; Portland likewise states that a permitted accessory structure within 3 feet of a shared property line must be fire-rated. However, current ORSC R302.1 expressly exempts detached nonhabitable accessory structures that are themselves exempt from permits from wall protection based on location on the lot, although projections may not extend over the lot line.
Permit & Review Path
Permit / Review Path
A qualifying detached, one-story, nonhabitable shed within the size and height exemption does not need a building permit, but it must still comply with zoning and may need a zoning permit in special circumstances. A shed that is over the exemption thresholds, attached, or habitable follows Portland's building permit process through Development Hub PDX. The City reviews building permits through intake, technical review, and pre-issuance; after issuance, required inspections must be completed. Building and applicable trade permits may be combined in a Residential Combination permit package.
Trade Permits & Professional Design
Trade Permit Rules
Electrical, plumbing, and mechanical permits are required when the shed includes work regulated by those trades. The ORSC states that trade permits may still be required for work that is exempt from a structural building permit. When a building permit is required, Portland allows structural and trade work to be submitted individually or together as a Residential Combination permit package.
Professional Design Rules
Ordinary prescriptive shed construction does not always require a design professional. Portland requires a geotechnical engineering report prepared by an Oregon-registered engineer when the site slope exceeds 20%. If an engineered lateral-load method is used, drawings, details, and calculations must be prepared and stamped by a licensed design professional. Pole buildings and pre-engineered metal buildings must also have plans and calculations prepared and stamped by a licensed design professional.
What You Need Before Applying
Requirements
Determine whether the shed is detached and nonhabitable, confirm its area and height, and verify zoning placement and site constraints. A shed that does not qualify for the detached accessory-structure exemption must follow the building permit process and applicable Oregon Residential Specialty Code and Portland Title 11, Title 24, and Title 33 requirements. All sheds must comply with zoning even when no building permit is required. Electrical, plumbing, or mechanical work can require separate trade permits.
Required Documents
For a building permit, Portland requires a completed building permit application and construction drawings including a site plan, architectural plans, and structural plans. Site-specific submittals may include a geotechnical engineering report for a site slope over 20%, an erosion-control plan or simple erosion-control form for ground disturbance, tree-preservation information where applicable, and a stormwater plan when more than 1,000 square feet of impervious area is added. A stand-alone zoning permit requires scaled plans; depending on scope, these may include a site plan, grading plan, landscape and tree plan, floor plans, and exterior elevations.