Snohomish County, WA Solar Energy: Panel Permits (2026)
Key Facts
- Governing section
- SCC 30.50.103(3)(h)(ii)
- Mechanical permit exempt
- Single-family rooftop PV meeting 11 criteria
- Electrical permit
- Always required, no exception
- Panel weight limit
- 3.5 to 5 psf depending on mount/slope
- Max panel height
- 18 inches above roofing surface
- Other systems
- Construction permit under SCC 30.53A.332.44
- Unpermitted work penalty
- Investigation fee, SCC 30.50.162
Summary
Rooftop solar photovoltaic systems on detached single-family homes in unincorporated Snohomish County skip the mechanical permit if they meet the eleven-point checklist in SCC 30.50.103(3)(h)(ii): engineered mounting, roof-compliant weight limits, and proper flashing. Every system still needs an approved electrical permit, and larger or non-residential installations follow the standard construction permit process instead.
Specific to the residential code: ... (ii) Photovoltaic (PV) panels meeting all of the following criteria: (A) PV system is designed and proposed for a detached single-family house. (B) PV system is designed for the rooftop of a house in compliance with applicable codes... (E) PV system has an approved and issued electrical permit. (F) To address uplift, panels are mounted no higher than 18 inches above the surface of the roofing to which they are affixed, and except for flat roofs, no portion of the system may exceed the highest point of the roof. (G) Total dead load of panels, supports, mountings, raceways and all other appurtenances weigh no more than: (I) Three and one-half pounds per square foot (PSF)... (K) The house is code compliant with setbacks and height, or the code allows expansion of nonconformity for solar panels.
Official source re-checked September 8, 2026: no newer edition of the code had been published (publisher’s edition: current through legislation passed August 12, 2026).
Full Breakdown
103 lists work exempt from a construction permit, and subsection (3)(h)(ii) carves out rooftop photovoltaic panels on a detached single-family house from the mechanical permit only if the installation meets every listed criterion. The system must be engineered and designed for PV, mounted on a lightweight roof such as shingles, and installed with manufacturer-specified attachment and roof-penetration weatherproofing. To limit wind uplift, panels may sit no higher than 18 inches above the roofing surface and, except on flat roofs, no part of the array may exceed the roof's highest point.
Total dead load is capped at three and one-half pounds per square foot, rising to four and one-half pounds for frameless panels on a roof sloped at least three-in-twelve, and five pounds for frameless panels on at least a five-in-twelve slope, with the load spread across enough roof-framing members that no point carries more than 50 pounds. The house must also stay compliant with setback and height rules, or fall under a code allowance for expanding a nonconformity for solar. Criterion (E) requires an approved and issued electrical permit regardless of the mechanical exemption, so no PV installation in the county is entirely permit-free. 44, added by Amended Ordinance 21-031, effective July 25, 2021, which covers installing or modifying solar photovoltaic power systems.
Violations & Fines
Starting mechanical or electrical work on a solar installation before the required permit issues triggers an investigation penalty under SCC 30.50.162, billed per the hourly schedule in SCC 30.86.400(9) in addition to the standard permit fee. A rooftop system that misses even one of the eleven exemption criteria in SCC 30.50.103(3)(h)(ii), such as exceeding the weight or height limits, no longer qualifies for the mechanical-permit exemption and needs a full permit before work proceeds.
Frequently Asked Questions
Do I need a permit for rooftop solar panels in Snohomish County?
What if my solar system doesn't meet all eleven exemption criteria?
Is an electrical permit still needed if the mechanical permit is exempt?
How heavy can my solar panel system be under the exemption?
What happens if I install solar panels before getting a permit?
Sources & Official References
Other rules in Snohomish County
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