How Salem Handles Accessory Structures: A Practical Guide
Salem maintains 123 local ordinances across all categories, and 4 of those deal specifically with accessory structures. Here is a breakdown of what the city actually requires, what is prohibited, and where Salem falls on the strict-to-permissive spectrum compared to other cities.
ADU Rental Restrictions
Salem bars accessory dwelling units from operating as short-term rentals or accessory short-term rentals. The rule sits in the special-use standards at SRC 700.007(a)(6), and applies to every ADU in the city regardless of zone once the unit is designated a special use.
Key details: Governing section: SRC 700.007(a)(6). Rule: ADUs barred from short-term/accessory short-term rental use. Max ADU size: 900 sq ft or 75% of main building. Lot limit: One ADU per lot. Detached ADU height cap: 25 feet.
Renting an ADU short-term is a UDC use violation, not a permitted deviation. Because SRC 700.005(d) blocks conditional-use approval as a workaround for special-use standards, a property owner cannot apply for relief; the City's code enforcement division pursues compliance under SRC chapter 20, which can include a notice of violation, civil penalties, and an order to cease the rental use until the ADU reverts to standard occupancy.
Compared to other cities, Salem takes a harder line on adu rental restrictions. The enforcement and penalty structure reflects that.
ADU Impact Fees
Salem charges system development charges (SDCs), its impact fees for water, wastewater, stormwater, transportation, and parks capacity, on nearly every new development citywide, but SRC 41.150(a)(9) carves out a blanket exemption for 'any accessory dwelling unit.' A new ADU in Salem therefore owes no SDC at building permit issuance, unlike most other new residential construction, which pays the charge under SRC 41.110.
Key details: ADU SDC status: Fully exempt under SRC 41.150(a)(9). Standard SDC trigger: Building permit issuance (SRC 41.140(a)). SDC categories: Water, wastewater, stormwater, transportation, parks. Fee-setting authority: Set by Council resolution, adjusted annually. Appeal window: 10 days to challenge a calculation.
There is no penalty specific to the ADU exemption itself since no charge is owed. But if a permit is later found to be misclassified, for example an accessory structure that does not qualify as an accessory dwelling unit, the City may recalculate and bill the omitted system development charge, and a person who disputes that calculation must file a written challenge with the Director within ten days of receiving it (SRC 41.180(a)).
The rules around adu impact fees in Salem lean permissive, but that does not mean anything goes.
Shed & Carport Rules
In Salem's RS single family zone, a shed or other accessory structure must sit at least 5 ft from an interior side line, stay within 15 ft in height, cover no more than 25% of the rear yard, and fit under an aggregate square footage cap tied to the size of the house: 600 sq. ft. for a main building of 1,200 square feet or less.
Key details: Interior side setback: Min. 5 ft. for most accessory structures; none against a fence wall on an infill lot. Rear setback: None up to 9 ft. tall; 1 ft. per 1 ft. of height over 9 ft.. Maximum height: 15 ft. for accessory structures. Rear yard coverage: Max. 25% for single family and two family accessory structures. Total square footage: 600 sq. ft. if house is 1,200 sq. ft. or less.
Section 511.010 states development standards only and prints no fine or penalty of its own. A shed that crosses the 5 ft. side setback, exceeds 15 ft. in height, pushes rear yard coverage past 25%, or pushes the combined accessory structure total past the Table 511-5 cap fails the RS zone standards. Salem treats those standards as conditions of development approval, so the practical consequence is a denied permit or a correction order to move, shrink or remove the structure. Rebuilding a damaged noncompliant shed is allowed only in its original location under subsection (g).
ADU Rules
Salem caps an accessory dwelling unit at 900 square feet or 75 percent of the main house's gross floor area, whichever is smaller, and limits detached ADUs to 25 feet in height. Only one ADU is allowed per lot, and it cannot be split off in separate ownership from the main house under SRC 700.007.
Key details: Size cap: 900 sq ft or 75% of main building, whichever less. Height limit: 25 feet for detached ADUs. Lot coverage: 60% maximum, all buildings combined. Street setback: 12 ft local street, 20 ft collector/arterial. ADUs per lot: One accessory dwelling unit per lot.
Building an accessory dwelling unit that exceeds the 900-square-foot or 75-percent size cap, the 25-foot height limit, or the Table 700-1 setbacks violates SRC 700.007 and Salem's Unified Development Code. The City issues a correction order under SRC chapter 20J, and the enforcement officer may assess a civil penalty if the violation is not corrected by the deadline, is intentional, or repeats a prior violation, with appeal rights under SRC 20J.190.
The Bottom Line
Salem's accessory structures rules are a mixed bag. Some areas are strict, others are relaxed, and the details matter. The best approach is to check the specific rule that applies to your situation rather than assuming Salem is broadly strict or permissive.
All of the above reflects Salem's municipal code as of our last review. If you need specifics on fines, exemptions, or filing requirements, the detailed ordinance pages linked above have the full breakdown.