Seattle City – Solar Permit Requirements

Seattle has developed a comprehensive guide to assist homeowners and businesses in installing solar electric systems. This guide provides crucial advice and outlines key steps for installing a solar PV (photovoltaic) system.

Key points in the guide include requirements for electrical, building, land use, and setback yards. Electrical permits are mandatory for any solar electric project and must be obtained by an electrical contractor. The fee for an electrical permit is roughly $239 (3/4 base + $65.65 admin fee) for systems smaller than 7.7 kW.

Building permits are not necessary if:

1. The solar electric system is planned for a single-family house rooftop.
2. The mounting system is specifically engineered for solar electric installations.
3. The roof is constructed of lightweight materials like shingles.
4. Panels do not extend over 18 inches above the roof’s surface.
5. The system does not surpass the highest point of a pitched roof.
6. The total weight (dead load) of panels, supports, mountings, and accessories does not exceed 5 pounds per square foot.
7. Supports are distributed across multiple roof framing sections to avoid exceeding 50 pounds of load on any section.
8. The mounting system’s specifications for attaching to the roof are followed.
9. Weatherproofing for roof penetrations is adequately addressed.
10. The structure complies with land use regulations including setbacks and height.
11. Fire code requirements are adhered to.

Building permits may be required for:

1. Residential rooftop solar electric systems that do not meet all the above criteria.
2. Commercial or industrial solar electric installations.
3. Non-rooftop solar electric systems needing standalone support structures.
4. Solar electric systems included in building alterations or additions valued over $6,000 (excluding the solar equipment value).

Land use rules specify that in certain zones, solar panels can extend up to 4 feet above the height limit or the ridge of the roof, without exceeding a total of 9 feet above the height limit.

Regarding setback yards, ground or pole-mounted PV systems must not be placed in front yards and should maintain a 15-foot distance from the property line and 3 feet from the side property line.

For a comprehensive understanding of all requirements, refer to the Seattle Guide.