Seattle City - Solar Permit Requirements

Seattle has created a guide to help home and business owners install a solar electric system. The guide gives advice and outlines important steps to take to install a solar PV (photovoltaic) system.

The guide includes electrical, building, land use, and set-back yard permit requirements. Any solar electric project must obtain an electrical permit secured by an electrical contractor. An electrical permit fee is approximately $239 (3/4 base + $65.65 admin fee) if you system size is less than 7.7 kW.

A building permit is not required under the following conditions:

• The solar electric (photovoltaic) system is designed and proposed for a rooftop of a single-family house.
• The mounting system is engineered and designed for solar electric systems.
• The rooftop is made from lightweight material such as shingle.
  „ Panels aren't mounted higher than 18” above the surface of the roof where they will be attached.
• None of the system may exceed the highest point of a pitched roof.
• The total (dead load) weight of the panels, supports, mountings, raceways, and all other accessories isn't more than 5 pounds per square foot.
• The supports for the solar panels are installed to spread the weight across as many roof framing sections as needed to ensure that at no point are loads in excess of 50 pounds exerted on a single section.
• The attachment to the roof is specified by the mounting system manufacturer.
• The method and type of weatherproofing roof penetrations, such as grommets or flashing, are provided.
• The structure meets land use regulations, such as
  setbacks and height.
• Fire code requirements are met.

A building permit may be required under the following conditions:

• Residential rooftop solar electric systems do not meet all of the above.
• The solar electric system is for a commercial or industrial application.
• The solar electric systems are not on a rooftop and require standalone support structures on the ground.
• The solar electric system is part of building alterations or additions, valued over $6,000 (not including the value of the solar equipment)
  

The land use requirements for single family, multi-family and residential small lot zones are solar panels may be mounted to extend up to 4 feet above the zone’s height limit, or up to 4 feet above the ridge of the pitched roof. The total height may not extend more than 9 feet above the zone’s height limit.

The set-back yard requirements are that ground or pole mounted PV systems cannot be located in front yards. They must be 15 back from the property line and 3 feet from the side property line.

For a full list of requirements and further details see the published Seattle Guide.