Contra Costa County, CA Solar Energy: Expedited Solar Permitting (2026)
Key Facts
- System size cap
- 10 kW AC or 30 kW thermal
- Building type
- Detached single-family or duplex only
- Application
- May be filed electronically
- Review timeline
- Per CA Solar Permitting Guidebook
- Operation barred
- Until compliance verified in writing
Summary
Contra Costa County must process small residential rooftop solar permits through the state-mandated expedited, streamlined review created by Section 718-12.004. The county building official posts a standard application, plan form, and checklist online, deems applications complete or incomplete in writing, and reviews complete submittals on the timeline set in the California Solar Permitting Guidebook before issuing the permit.
The following expedited, streamlined permitting process applies to applications for a building permit to install a small residential rooftop solar energy system: (a)Application... An application to install a small residential rooftop solar energy system may be submitted electronically.(b)Application Review. An application will be deemed complete if the building official determines that the application includes all of the information and documents required by the standard application form, the standard plan form, and the standard checklist... the building official will perform an expedited review of the application and all submittals in substantial conformance with the timeline set forth in the then-current edition of the California Solar Permitting Guidebook published by the Governor's Office of Planning and Research.(c)Permit Issuance. A building permit will be issued following the building official's approval of an application... and after all required fees have been paid.(e)(1)The system is no larger than ten kilowatts alternating current nameplate rating, or thirty kilowatts thermal.
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: Ordinance Code: Supplement 103).
Full Breakdown
5. 004 layers a faster path on top of that for small residential rooftop systems: the county building official must publish the standard building permit application, plan form, and checklist on the county website, matching the most current California Solar Permitting Guidebook from the Governor's Office of Planning and Research, and must accept applications submitted electronically. Once an application includes everything the standard forms require, the building official deems it complete; if anything is missing, the applicant gets written notice of exactly what's needed. From there, the building official's review must substantially conform to the Guidebook's expedited timeline, and the permit issues, electronically if the application was filed that way, once approved and all fees are paid.
To qualify for this fast lane, the system can be no larger than ten kilowatts AC (or thirty kilowatts thermal), must meet all applicable fire, building, and electrical codes and Civil Code Section 714, must sit on the rooftop of a detached single-family home or duplex, and can't exceed the zoning district's building height limit. After installation, the building official inspects the system, and it cannot legally operate until the official verifies in writing that it complies with the permit; noncompliant installs get a written notice of what needs fixing before reinspection.
Violations & Fines
A small residential rooftop system that isn't installed to the approved building permit can't be operated: Section 718-12.004(d) bars operation until the building official verifies compliance in writing. If an inspection turns up noncompliance, the building official notifies the permittee of the corrective steps required and schedules additional inspections until the system passes, on top of any other permit or code enforcement the county pursues.
Frequently Asked Questions
How fast does Contra Costa County have to review a rooftop solar permit?
Can I submit my solar permit application online?
Does my system qualify for the expedited process?
Sources & Official References
Other rules in Contra Costa County
California rules heatmap·Compare Contra Costa County to another location·View the California solar energy overview
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