Solano County

A city address is usually permitted by the city, not the county — but not always, and some authorities keep building and hand electrical to someone else. Getting this wrong costs the whole submittal, because every requirement below belongs to whoever actually holds jurisdiction. Check the overlays in the same pass: an HOA, a historic district, a windstorm certification or a system-size cap can reshape the design, and all of them are cheaper to find now than after the array is laid out.

• Is this authority the AHJ for residential solar at this address? Yes - for the UNINCORPORATED area only. Solano County Department of Resource Management, Building & Safety Services Division (675 Texas St., Suite 5500, Fairfield; 707-784-6765; building@solanocounty.gov) is the AHJ for residential solar in unincorporated Solano County. Inside the seven cities (Benicia, Dixon, Fairfield, Rio Vista, Suisun City, Vacaville, Vallejo) the city is the AHJ. 95% · department page
• What does this authority permit itself, and what does it delegate? Both, in one division. Building & Safety Services does the plan review, permit issuance and inspection for building AND electrical work - Solano County Code 6.3-02(c) defines 'building department, electrical department, plumbing department' all to mean the county 'building division'. Two other Resource Management divisions touch GROUND-mount PV only: Planning Services charges a Building Permit Plan Review for 'Structures Other than Building (includes ground mount photovoltaic systems)' and Environmental Health charges a 'Building Permit Review - ground mount photovoltaic system only'. Neither appears for roof-mount. Fire-code enforcement in the field sits with the independent fire protection districts. 85% · ordinance
• Is a permit required for a residential rooftop PV system? Yes. A building permit is required; rooftop PV is not on the county's amended CBC 105.2 exemption list (which exempts only sheds under 120 sq ft with no utilities, fences, oil derricks, low retaining walls, small water tanks, sidewalks/driveways, finish work, stage sets, small above-ground pools, shade cloth, playground equipment, small awnings, low fixtures, plus the county additions of satellite dishes, small agricultural buildings on 20+ acres and most fencing). 90% · department page
• Is there a separate electrical permit, or is it combined? Combined. One permit - 'Photovoltaic Electrical System - roof mount' - covers the installation; there is no separate solar electrical permit line anywhere in Building & Safety fee Exhibit III-C, and County Code 6.3-02(c) makes the building division the electrical department too. 70% · fee schedule
• Is a HOA or architectural approval required first? No. County Code 6.3-16.030(c) is explicit: 'Staff's approval of an application shall not be conditioned on the approval by an association, as defined in Section 4080 of the Civil Code.' Nor is county architectural approval applied to a rooftop retrofit - zoning 28.102 reaches 'the external design of all proposed new uses, dwellings, buildings or structures', and Planning Services' Building Permit Plan Review fee list has lines for new dwellings, additions, pools, accessory structures and ground-mount PV but no line for roof-mount PV, i.e. Planning does not review a rooftop system at all. 80% · ordinance
• Is there a historic-district review? No. Solano County's zoning code establishes no historic district or historic-preservation overlay - Chapter 28's special overlay districts are Park (P), Travis Reserve Area (TRA) and Policy Plan (PP). Searching the whole of Chapter 28 for 'historic' returns only a museum definition, a historical-sign provision for abandoned signs, and a rule that a secondary or junior ADU on a property listed on the California Register of Historic Places needs a Zoning Administrator determination. Nothing touches solar. 75% · ordinance
• Is a wind or windstorm certification required? No. There is no wind or windstorm certification in Solano County. What the county publishes instead is a design criterion the plans must meet: 'Wind: Basic Wind Speed 93 MPH, Exposure C', alongside Seismic Design Category D, ground snow load 0 psf and a 12-inch minimum foundation depth. The Guidebook's Structural Criteria handles uplift prescriptively through the anchor-fastener check (5/16 inch lag screw with 2.5 inch embedment, or the manufacturer's guidance). 80% · department page
• Is a Specific Use Permit or Council approval ever required? No - not for residential rooftop or accessory-scale PV. County Code 6.3-16 makes small residential rooftop solar an expedited, staff-level approval, and the parallel EV-charging section 6.3-26.040(e) confirms the county's model that 'the building official shall issue a building permit, the issuance of which is nondiscretionary'. Use permits and Board involvement attach only to a 'Commercial Solar Energy Facility' - defined in zoning 28.01 as a system 'for the primary purpose of resale or off-site use' - which must post financial assurance for decommissioning before any grading or building permit issues. A household system that 'is used solely to meet or offset on-site electric load' falls in the 'Solar Energy System' definition instead, which 28.01 calls 'incidental to the land use of the property'. 80% · ordinance
• Is there a system-size cap on residential generation? No cap on system size. The 10 kW AC (or 30 kW thermal) figure in County Code 6.3-16.020(b) is the ELIGIBILITY threshold for expedited review, not a limit - a larger system simply goes through the standard process. The real limits are dimensional and utility-side: zoning 28.93(A)(5) allows a roof-mounted solar energy system to 'exceed the height limits of the primary or accessory structure, to a maximum of five feet above the roof surface'; 6.3-16.020(b)(4) requires the array not to exceed the maximum legal building height; a ground-mount system 'shall comply with the development standards of the zoning district for accessory structures'; and generation sized for resale rather than on-site load reclassifies the project as a Commercial Solar Energy Facility needing a use permit. 80% · ordinance

Several authorities require the electrical permit to be pulled by a licensed electrician, or require the contractor to be registered with them BEFORE applying. Registration is not same-day. This is second on the list rather than fourth because it is the step most likely to stop the job before the drawings matter.

• Who is allowed to pull the electrical permit? Either. County Code 6.3-12: 'Applications are to be signed by the property owner or a duly licensed contractor, engineer, architect, or authorized agent designated by the property owner.' The department page adds 'Permits may only be issued to a licensed contractor or the property owner or their certified agent. (Contractors License and Workers Compensation Insurance verification required).' There is no separate electrician-only rule. NOTE: the SolarAPP+ fast route is restricted - 'Only licensed contractors registered with SolarAPP+ are eligible to apply'. 90% · ordinance
• Must the contractor be registered with this authority before applying? No county contractor registration. The county verifies the CSLB licence and workers' compensation insurance at issuance rather than pre-registering contractors. The ONE registration that does exist is external: to use the county's SolarAPP+ route the contractor must be registered with SolarAPP+ at solarapp.nrel.gov, not with Solano County. 80% · department page
• Is a homeowner permitted to self-install and self-permit? Yes. County Code 6.3-12 and 6.3-01 both preserve owner-builder work - 6.3-01 says 'nothing in the codes adopted in this chapter shall be construed to prevent any person from performing his own building, mechanical, plumbing or electrical work when performed with the permits in compliance with this chapter, and the California Business and Professions Code.' A homeowner cannot use the SolarAPP+ route (licensed contractors only) but can apply through the normal online portal. 85% · ordinance

Almost everywhere wants a site plan, a one-line or three-line electrical diagram, equipment cut sheets with listings, and a structural attachment detail. Build it against the published checklist rather than the last jurisdiction you worked in — the checklist is what the reviewer marks against.

• What documents make up a complete submittal? Under County Code 6.3-16.030(a) a small residential rooftop PV application 'shall include the checklist and applicable standard plan contained in the most current version of the California Solar Permitting Guidebook adopted by the Governor's Office of Planning and Research' - which the county hosts on its own Documents page. That package is: (1) completed permit application; (2) the Eligibility Checklist for Expedited Solar Photovoltaic Permitting; (3) the completed Solar PV Standard Plan (central/string inverter, or microinverter/ACM version) with its equipment, conductor, cable and conduit schedules; (4) a roof plan showing panel layout, approximate roof access point, code-compliant access pathways, PV system fire classification and the locations of all required labels and markings; (5) the completed Structural Criteria for Residential Flush-Mounted Solar Arrays sheet with racking manufacturer worksheets; and, where the standard plan is not used, an electrical plan with one-line diagram, module/string counts, inverter make and model, grounding/bonding, conductor and conduit types and sizes, equipment cut sheets, CEC Article 690/705 labelling and a site diagram with north arrow, lot dimensions and distances to property lines. Everything is uploaded to the Accela portal. 80% · adopted checklist
• How many copies, and in what format? Electronic only, one set. 'Apply online and submit all drawings electronically'; 'All plans shall be signed by the person responsible for their preparation... Electronic signatures are acceptable'; 'Project address, parcel number, project data, and scope of work shall be noted on the first sheet of plans.' County Code 6.3-16.030(b) additionally requires that applications 'be accepted through electronic submittal, and electronic signatures shall be accepted in lieu of a wet signature.' No paper-copy count is published. (The only paper survivor is fire sprinkler plans - two sets - which is irrelevant to PV.) 85% · department page
• Is a site plan required, and what must it show? Yes. For the expedited solar path the Guidebook's Standard Plan requires a site diagram 'showing the arrangement of panels on the roof or ground, north arrow, lot dimensions and the distance from property lines to adjacent buildings/structures (existing and proposed)', plus a separate roof plan showing roof layout, PV panels, approximate location of the roof access point, location of code-compliant access pathways, the PV system fire classification and the locations of all required labels and markings. The Structural Criteria sheet separately requires 'a roof plan of the module and anchor layout'. The county publishes a Sample Site Plan on its Documents page showing what a site plan should contain. 80% · adopted checklist
• Is a one-line / three-line diagram required? Yes. The Solar PV Standard Plan the ordinance adopts IS a single-line diagram form with numbered fill-in steps; where the standard plan is not used the submittal must include a 'One-line diagram of system'. PG&E separately requires a single-line diagram with the AC disconnect 'clearly marked on the submitted single-line diagram indicating the manufacturer, model type, voltage rating, current rating, and location', and requires a single-line diagram in the PTO package. 90% · adopted checklist
• Are string and conductor calculations required? Yes, in the fill-in form rather than as separate hand calculations. The Standard Plan's Conductor, Cable and Conduit Schedule must be completed for each tagged run (conductor type, conductor size, number of conductors, conduit/cable type, conduit size, EGC and GEC), and the eligibility gates require module Isc under 13 A, strings not combined ahead of the inverter, no more than two inverters and a 225 A or smaller bus bar; the plan carries the CEC 690.7/690.11 max-VOC tables and the CEC 705.12(D)(2)(3)(b) bus-bar table to be worked against. Full stand-alone string and conductor calculations are only needed for systems that fall outside the standard plan. 70% · adopted checklist
• Is a structural PE stamp required, and at what threshold? Only when the flush-mount Structural Criteria sheet fails. If every item on 'Structural Criteria for Residential Flush-Mounted Solar Arrays' is checked YES - single roof with no reroof overlay, structure sound, modules parallel to the roof plane, 2 to 10 inch gap under the module, no overhang of ridges/hips/gables/eaves, modules plus supports no more than 4 psf, array covering no more than half the total roof area, anchor spacing within Table 1 and 5/16 inch lag screws with 2.5 inch embedment or the manufacturer's fastener guidance - then 'No additional calculations are required'. If one or more items are NO: 'Attach project-specific drawings and calculations stamped and signed by a California-licensed civil or structural engineer.' There is no kW or area threshold. 85% · adopted checklist
• Is an electrical PE stamp required, and at what threshold? No. Nothing in County Code Chapter 6.3, the fee schedule or the adopted Guidebook requires an electrical PE stamp at any size for residential PV. The only stamp trigger published is structural, and only when the flush-mount criteria fail. County Code 6.3-13 requires state-licensed design only for occupancy groups A, B, E, F, H, I, L, M, R-1, S and U - R-3 dwellings are deliberately absent from that list. 75% · ordinance

Most authorities now take the whole application through a portal, and several states cap or constrain what a residential solar permit may cost. Check whether plan check is billed separately before you quote the job.

• Which permit portal does this authority use? Accela Citizen Access, branded 'Solano County Online Permits' / 'Solano County Citizen Portal', at aca-prod.accela.com/solano (also reached as /SOLANOCO). It carries Submit an Application, Search Records, File Complaint, My Records, Pay Fees, Schedule an Inspection and Connect to an Existing Record. For solar there is a second, upstream system: SolarAPP+ at solarapp.nrel.gov, where the automated plan review happens before the Accela application is made. 90% · portal
• Can the whole application be completed online? Yes. 'All building permit applications must be submitted online. You will be able to upload drawings and documents with your permit application.' Plans go in electronically, electronic signatures are accepted in lieu of wet signatures (Code 6.3-16.030(b)), fees are paid through the portal or the county's Link2Gov payment page, and inspections can be requested through the portal as well as by phone. For solar the plan review itself can also be done online and automatically through SolarAPP+. 90% · department page
• What does a residential solar permit cost? $194 for a roof-mount residential PV system (FY2026/27 recommended fee, effective 1 July 2026), plus a $10 micrographics/document-storage charge per permit. Ground-mount is far more: $581 to Building & Safety, plus a $282 Planning Services plan review for 'Structures Other than Building (includes ground mount photovoltaic systems)' and a $138 Environmental Health 'Building Permit Review - ground mount photovoltaic system only' - about $1,001 before micrographics. The prior-year roof-mount fee was $184. 75% · fee schedule
• How is the fee calculated? Flat. Roof-mount PV is a single listed flat fee ($194) explicitly authorised under Gov. Code 66015(a)(2) and (b)(2), not under the county's general valuation method. That matters: Solano's DEFAULT building fee is valuation-based - 'Building permit fees are those prescribed in the 2001 California Building Code, Chapter 1, Section 107.2 & Table 1-A, except buildings shall be valued per the table published by the Building Standards Journal in May 2003 applied to the... Square Foot Construction Costs table published by the International Code Council in February 2026' - and the flat PV line is what keeps solar out of that machinery, as Gov. Code 65850.55 requires. 85% · fee schedule
• Is there a separate plan-check fee? No separate plan-check fee is published for roof-mount PV - the $194 is one listed flat fee and Exhibit III-C carries no PV plan-review line. Two cautions: (a) the county's general rule is that 'the plan review fee shall be as set forth in the 2001 California Building Code, Chapter 1, Section 107.3 and Table 1-A', which would apply to anything not separately listed; and (b) the Submittal Checklists page says 'Plan check fees are due at time of submittal. Final permit fees are due at the time of permit issuance', implying the flat fee is split across the two moments rather than that a second fee exists. Ground-mount PV genuinely does attract separate reviews (Planning $282, Environmental Health $138). 55% · fee schedule

Interconnection is a separate process from the permit and usually the longer pole. Where the utility does not depend on the permit being issued, running both at once is the single biggest saving available on a residential job.

• What is the stated plan-review turnaround? For the SolarAPP+ route: automated, effectively instant - 'Licensed contractors are eligible for automated residential solar plan review using SolarAPP+'; the contractor gets an approval ID from solarapp.nrel.gov and then applies to the county with it. For the standard route the county publishes NO turnaround. The Building Permit Steps page says only 'After you submit your building permit application and pay plan review fees, we will review to make sure your plans meet minimum Building Code requirements' with no number attached, and the adopted Guidebook's template turnaround sentence ('Permits not approved over the counter should be reviewed in [ONE TO THREE] days') is left with its bracketed placeholder unfilled. California sets no statutory review deadline for solar. 60% · department page
• How long is an issued permit valid before it expires? Two years from issuance, but only if inspections keep happening: 'Your permit expires if you do not pass inspections within 12 months of the date of issue or the date of a previous inspection. As long as you pass inspections every 12 months, your permit is valid for 2 years from the issue date.' County Code 6.3-14(b) puts the same rule in the ordinance for R-3 and U occupancies - 'valid for two years from the date of their issuance, provided that the time limits of starting work or work stoppage are met'. A Permit Extension is available for $102 (FY2026/27), with a request form on the Documents page. 90% · department page
• Which utility handles interconnection here? PG&E (Pacific Gas and Electric) - it owns the distribution system in unincorporated Solano County and it is PG&E, under CPUC Electric Rule 21, that receives the interconnection application, does the engineering review, changes the meter and grants permission to operate. MCE (Marin Clean Energy) is NOT the interconnecting utility: MCE is the Community Choice Aggregator that supplies the GENERATION, and unincorporated Solano County joined MCE in 2020. In MCE's own words, MCE supplies 'the electricity that PG&E would usually provide, called generation', while 'PG&E delivers the electricity through power lines that they own'; MCE's NEM page likewise says 'PG&E will continue to charge you for all electricity delivery (non-generation) services.' Being an MCE customer changes the export compensation and the billing, not who you interconnect with. 90% · utility / CCA
• Where does the utility sit in the sequence? Parallel, with a hard dependency at the end. PG&E's sequence is: the contractor 'completes an application to connect your system to the PG&E electric grid' EARLY - 'Ensure that your contractor fills out the Interconnection Agreement application early. This way you can start generating energy shortly after your system passes local city or county inspections' - so the interconnection application runs alongside the county permit rather than after it. But PTO is gated on the county: to get permission to operate the contractor must submit 'The Interconnection Application, a single line diagram of the system, and a copy of the final building permit'. So: apply to PG&E in parallel, finish with the county, then close out with PG&E. PTO typically takes 5 to 10 business days after PG&E has the paperwork, up to a maximum of 30. 90% · utility process page

The NEC edition a jurisdiction enforces is often a cycle behind the newest one published, and local amendments sit on top of it. Rapid shutdown, conductor sizing and labelling all change between editions, so the edition in force is the first thing to establish, not the last.

• Which NEC edition is in force? 2023 NEC - adopted as the 2025 California Electrical Code (Title 24 Part 3) at County Code 6.3-03(a)(4), in force since 1 January 2026. WARNING - THE COUNTY'S OWN PAGE IS WRONG ON THIS: the General Permitting Requirements page says 'Electrical - 2025 CEC (based on the 2024 NEC)'. There is no 2024 NEC; the NFPA publishes in odd years (2020, 2023, 2026) and the 2025 CEC is built on the 2023 NEC. The county's other four entries on that same line are right (2024 IBC, 2024 IRC, 2024 UMC, 2024 UPC, 2024 IFC), so this reads as a copy-paste slip down the column rather than a claim about a different edition. The adopting ordinance says only '2025 Edition', which is correct and is what governs. 90% · adopting ordinance
• Which building code edition is in force? 2025 California Building Code and 2025 California Residential Code, adopted by reference at County Code 6.3-03(a)(2) and (a)(3) - CBC with Appendices C, F, G, I and J. The department page confirms: 'Plans shall be drawn using the 2025 California Building Code (based on the 2024 IBC)' and 'Residential - 2025 CRC (based on the 2024 IRC)'. Solano is CURRENT, not stale - the whole 2025 Title 24 family is adopted (Administrative, Building, Residential, Electrical, Mechanical, Plumbing, Energy, WUI, Historic, Fire, Existing Building, Green, Referenced Standards), together with the 1997 Uniform Code for the Abatement of Dangerous Buildings. 95% · adopting ordinance
• Which fire code edition is in force? 2025 California Fire Code - and it is adopted twice, by two different bodies. County Code 6.3-03(a)(10) adopts the 2025 CFC with Appendix Chapter 4 and Appendices B, BB, C, CC, D, E, F, G, I and J. Separately, Ordinance No. 25-01, the Solano County Consensus Fire Ordinance, adopts 'all chapters of the 2025 California Fire Code... including Appendix's B, BB, C, CC, D, E, F, G, H, I, O, and P as amended' for the Cordelia, Dixon, Montezuma, Suisun and Vacaville Fire Protection Districts, repealing Ordinance 22-01. Two internal defects worth knowing: the ordinance's amendment block is still captioned 'Amendments made in the 2022 California Fire Code', and its effective-date clause reads 'This Ordinance shall become effective on January 1, 2025' although the code it adopts took effect 1 January 2026. 85% · adopting ordinance
• Are there local amendments to any of the above? Yes - several, but none of them touch solar. County Code Chapter 6.3 amends: CBC 110.3.10 (final inspection scope, 6.3-18); CBC 1505 (roof coverings - Class B minimum countywide, Class A in Very High Fire Hazard Severity Zones and WUI areas, including reroofs over 50%, 6.3-19); CBC 105.2 (three added permit exemptions, 6.3-20); CBC 107 (standard plans, 6.3-21); commercial conduit (6.3-22); CEC 230.79(C) (200 A minimum service, 6.3-23); and adds CFC 110.4 (hazard abatement, 6.3-24). The fire districts' Ordinance 25-01 adds its own CFC amendments (fire access roads, bridge load ratings, gate operators, NFPA 13D/13R/24/72 2025 editions) - again none about PV or ESS. Chapter 6.3 also exempts the unincorporated county from the Solar Shade Control Act (6.3-80). 85% · ordinance
• What is the installation judged against? The 2025 California Electrical Code (2023 NEC) as adopted at County Code 6.3-03(a)(4), including NEC Article 690 with no California amendment, plus the county's own CEC 230.79(C) amendment at 6.3-23, plus the approved plan set. The Guidebook standard plan the county adopts works to CEC Articles 690 and 705 throughout - 690.7/690.11 max-VOC tables, 690.12 rapid shutdown, 705.12(A) supply-side and 705.12(D)(2)(3) load-side connection rules with the bus-bar table. Note the adopted Guidebook is the 2019 4th Edition and cites the older CEC numbering (690.35(F), 690.53, 690.54, 690.31(G)(3)) and CRC R324; under the 2025 code cycle solar renumbered to CRC R329 and several of those 690 sections have changed, so the installation is judged against the 2025 CEC even where the county's handout still prints 2016-era citations. 80% · ordinance

Ridge setbacks and roof access pathways are fire-service requirements and they constrain the array layout. They are the most common cause of a redesign after the fire department comments on a plan set.

• What ridge setback and access pathways are required? The state requirement, unamended: 2025 California Fire Code Chapter 12 (solar moved from CFC 1204 to 1205 in this cycle) and CRC R329 (formerly R324) as adopted at County Code 6.3-03. Solano adds nothing of its own - neither Chapter 6.3 nor the fire districts' Ordinance 25-01 amends the solar access-pathway or ridge-setback provisions. What the county DOES require is that the pathways be drawn: the adopted Guidebook makes the roof plan show 'approximate location of roof access point, location of code-compliant access pathways, PV system fire classification and the locations of all required labels and markings', and points installers to the State Fire Marshal Solar PV Installation Guide for examples of clear-path access pathways. Fire Hazard Severity Zones matter here - OSFM released updated LRA maps for Solano on 24 February 2025 and the county has enforced LRA construction requirements in unincorporated areas since July 2025. 70% · ordinance

Which rapid-shutdown rule applies follows directly from the NEC edition in force, and the initiation device has to be at a location the fire service can reach and identify. This is inspected, and it is labelled.

• Is rapid shutdown required, and to which NEC edition? Yes - to the 2023 NEC as adopted in the 2025 CEC, i.e. NEC/CEC 690.12. The adopted Guidebook spells out the county's expectations: 'The rapid shutdown initiation device shall be labeled according to CEC 690.56(C), and its location shall be shown on the site plan drawing'; a single initiation device 'shall operate all disconnecting means necessary to control conductors in compliance with CEC 690.12'; the device must be readily accessible, suitable for the environment and listed as a disconnecting means; and the voltage reduction must be either verified in the field or achieved by equipment listed to UL 1741 with rapid shutdown capability. Acceptable methods include a UL 1741-listed inverter with input and output rapid shutdown capability, or a UL 1741-listed rapid shutdown system. 80% · adopted checklist

The NEC sets a baseline for permanent markings at the service equipment and the disconnecting means. On top of that, an authority may specify its own wording, and the utility may specify more again. Where any of them writes its own text, a generic off-the-shelf label set will not pass — this is the detail most often fixed on a return visit.

• Which placards does this authority require at the service equipment? Those required by CEC Articles 690 and 705 (the Guidebook says 'CEC Articles 690 and 705 and CA Residential Code Section R324 require the following labels or markings'), which for a typical residential system are: at the inverter output overcurrent device, 'WARNING - INVERTER OUTPUT CONNECTION; DO NOT RELOCATE THIS OVERCURRENT DEVICE' (705.12(D)(2)(3)(b), not required if the panelboard is rated not less than the sum of the ampere ratings of all overcurrent devices supplying it); at the service equipment, 'WARNING - DUAL POWER SOURCES, SECOND SOURCE IS PHOTOVOLTAIC SYSTEM, RATED AC OUTPUT CURRENT __ AMPS AC, NORMAL OPERATING VOLTAGE __ VOLTS' (690.54); on a new load centre where the busbar rule is not met, 'WARNING: THIS EQUIPMENT FED BY MULTIPLE SOURCES. TOTAL RATING OF ALL OVERCURRENT DEVICES, EXCLUDING MAIN SUPPLY OVERCURRENT DEVICE, SHALL NOT EXCEED AMPACITY OF BUSBAR' (705.12(D)(2)(3)(c)); at the AC disconnect, 'PV SYSTEM AC DISCONNECT - RATED AC OUTPUT CURRENT __ AMPS, AC NORMAL OPERATING VOLTAGE __ VOLTS'; at the DC disconnect, 'PV SYSTEM DC DISCONNECT' with rated max power-point current and voltage, maximum circuit current and maximum system voltage (690.53); 'WARNING - ELECTRIC SHOCK HAZARD, DO NOT TOUCH TERMINALS... MAY BE ENERGIZED IN THE OPEN POSITION' (690.17(E)); 'PHOTOVOLTAIC SYSTEM EQUIPPED WITH RAPID SHUTDOWN' at the initiation device (690.56(C)); 'WARNING: PHOTOVOLTAIC POWER SOURCE' on junction/combiner boxes and on conduit every 10 feet (690.31(G)(3)); plus the ungrounded-system and ground-fault warnings where applicable. PG&E adds one more at the service: permanent signage on the front of the AC disconnect reading e.g. 'UTILITY AC DISCONNECT SWITCH'. 80% · adopted checklist
• Does the authority specify placard wording of its own? No. Solano County authors no placard wording of its own. Chapter 6.3's amendments cover roofing, exemptions, standard plans, conduit, service panels, final inspection and fire hazard abatement - none is a signage provision - and the fire districts' Ordinance 25-01 adds none either. The wording the county enforces is the CEC's, reproduced in the Guidebook standard plan it adopts by reference; the only non-CEC wording in play is PG&E's 'UTILITY AC DISCONNECT SWITCH', which is the utility's requirement, not the AHJ's. 80% · ordinance
• Does it specify letter height, colour or material? The county specifies none itself; the specification it adopts by reference is the Guidebook's informational note: 'ANSI Z535.4-2011 provides guidelines for the design of safety signs and labels... A phenolic plaque with contrasting colors between the text and background would meet the intent of the code for permanency. No type size is specified, but 20 point (3/8") should be considered the minimum.' PG&E is harder-edged for the AC disconnect label: 'Labels shall be permanent and suitable for the environment and shall be engraved phenolic or comply with ANSI Z535.4. Lettering shall be a minimum 3/8" high and in all capitals.' 75% · adopted checklist
• Is a site plan / facility map placard required, and what must it show? Yes, in two forms. (a) Plan-stage: the adopted Guidebook requires a roof plan showing roof layout, PV panels, approximate roof access point, code-compliant access pathways, PV system fire classification and the locations of all required labels and markings, and a separate site diagram with panel arrangement, north arrow, lot dimensions and distances from property lines to adjacent buildings/structures; the rapid-shutdown initiation device's location must be shown on the site plan drawing. (b) On-site: 'CEC 705.12 requires a permanent plaque or directory denoting all electric power sources on or in the premises or rapid fire shutdown equipment.' PG&E adds its own map obligation - 'When the disconnect switch is not grouped with the meter panel provide a map showing the location', and the same for a Net Generation Output Meter that is not grouped with the other meters and the disconnect. 80% · adopted checklist
• Does the UTILITY specify placards beyond the AHJ's? Yes - PG&E requires signage the AHJ does not. Per PG&E document 060559 Rev. 07 (25 March 2022), 'Disconnect Switch Requirements for Distributed Generation Customers', which is also part of PG&E's Distribution Interconnection Handbook: 'Permanently attached signage on the front that explains this is the ac disconnect switch for the generation. Example: UTILITY AC DISCONNECT SWITCH.' 'Labels shall be permanent and suitable for the environment and shall be engraved phenolic or comply with ANSI Z535.4. Lettering shall be a minimum 3/8" high and in all capitals.' 'When the disconnect switch is not grouped with the meter panel provide a map showing the location.' 'If a Net Generation Output Meter (NGOM) is installed provide proper labeling as described and a map showing the location if not grouped together with the other meter(s) and disconnect switch.' The switch itself must also carry marking that clearly indicates the open (off) and closed (on) positions. MCE, as the CCA, specifies nothing here - it supplies generation only. 90% · utility DG manual
• Where must the labels be placed? At the equipment each label describes, per the Guidebook's marked-up standard plan: at the inverter output overcurrent device; at the AC disconnect; at the DC disconnect; at the service equipment / point of interconnection; on junction and combiner boxes and on the DC conduit at intervals of every 10 feet; at the rapid shutdown initiation device (whose location must also be shown on the site plan). The 705.12 plaque or directory denoting all power sources goes at the premises' service. PG&E's utility disconnect label goes on the FRONT of the AC disconnect switch enclosure, which must itself be within 10 feet of and in line of sight of the PG&E meter, at the same grade level if outdoors, mounted between 48 and 75 inches from ground to the top of the enclosure - never above grade level, never on a roof, and never in a room that is not an approved electric meter room. 85% · utility DG manual

Where the AC disconnect must sit relative to the meter is usually the utility's rule, not the building department's. Battery storage frequently carries its own permit, its own inspection and its own fire conditions.

• Where must the AC disconnect be, relative to the meter? Within 10 feet of the PG&E meter and in line of sight of it. PG&E 060559: 'The device must be physically located for ease of access and visible to PG&E employees within 10 feet of the meter. The device must be located in close proximity, or within line of sight, of the meter.' 'The disconnect device must be installed between the PG&E meter and all generation sources' and 'must be installed to only isolate the customer generation sources and must not disconnect customer loads.' If outdoors with the meter it must be at the same grade level; it is 'Not allowed on: any floor or level above grade, on a roof, or inside a room or area that is not an approved electric meter room'; wall- or pad-mounted it sits between 48 inches minimum and 75 inches maximum from ground to the top of the enclosure. It must be manually operated, gang-operated, visible-break, lockable open with a PG&E padlock taking a 5/16 inch shaft (keyed locks not allowed), and the neutral must not be switched. Molded-case circuit breakers and pull-out disconnects are not acceptable. 90% · utility DG manual
• Must equipment be on a specific approved list? No county-maintained approved list - but three listing constraints bite. (1) The adopted Guidebook requires that 'Listed and labeled equipment shall be installed and used in accordance with any instructions included in the listing or labeling (CEC 110.3)', and requires equipment cut sheets for inverters, modules, AC and DC disconnects and combiners. (2) The SolarAPP+ route only accepts equipment SolarAPP+ recognises, so choosing that path constrains equipment selection. (3) PG&E maintains an approved list for the AC disconnect specifically: 'PG&E-approved disconnect switch models, rated up to 1200 amps, currently listed in both the Eaton and Siemens Safety Switch Cross-Reference Guides, meet all of the functional requirements', and molded-case circuit breakers and pull-out disconnects are 'not acceptable as an approved disconnect switch'. Rule 21 also requires CPUC/CEC-listed smart inverters, which I did not verify from a primary source in this run. 60% · utility DG manual
• Are batteries permitted, and under what conditions? Yes, permitted - under the 2025 California Fire Code and 2025 CRC as adopted at County Code 6.3-03, with NO local overlay. Solano's zoning BESS ordinance (28.83) deliberately does not reach a household battery: it 'shall apply to all front-of-the-meter battery energy storage systems in the unincorporated territory of Solano County that have a rated nameplate capacity equal to or greater than 1,000 kilowatt hours', and 'The requirements of this section do not apply to behind-the-meter BESS supporting residential, commercial, agricultural, manufacturing and industrial uses.' So a home battery is governed by the state code (CRC R330, CFC Chapter 12, NFPA 855, UL 9540) and nothing county-specific. One practical consequence: adding a battery DISQUALIFIES the project from the expedited solar path - the adopted eligibility checklist requires 'Solar system is utility interactive and without battery storage' and 'System does not utilize storage batteries, charge controllers, or trackers' - so a solar-plus-storage job goes through the standard process. PG&E treats storage as in scope for the disconnect standard, which covers 'customer generation and energy storage systems'. 85% · ordinance
• Is there a separate ESS permit or inspection? No separate ESS permit type or ESS inspection is published. Building & Safety fee Exhibit III-C has lines for roof-mount PV, ground-mount PV, electrical service change 'other than photovoltaic', mechanical, plumbing, demolition and reinspection - and no battery or energy-storage line at all; there is no ESS submittal checklist among the Submittal Checklists accordions; and County Code Chapter 6.3 has expedited sections for rooftop solar (6.3-16) and EV charging (6.3-26) but none for storage. What the record does show is that a battery pushes the job off the expedited path into standard review, which in practice means more than the single inspection the solar ordinance guarantees. 50% · fee schedule
• Is a ground mount treated as a structure? Yes - materially more so than a rooftop system. Zoning 28.01 provides that 'A ground mounted solar energy system shall comply with the development standards of the zoning district for accessory structures', which brings setbacks, height and coverage into play. The fee schedule makes the consequences concrete: a ground mount draws a $581 Building & Safety fee based on 3 inspections (versus $194 and 1 inspection for roof-mount), a $282 Planning Services 'Building Permit Plan Review - Structures Other than Building (includes ground mount photovoltaic systems)', and a $138 Environmental Health 'Building Permit Review - ground mount photovoltaic system only' - the last being a Liquid Waste program fee, i.e. a septic/leachfield clearance. It is also outside the expedited solar path, whose eligibility checklist requires the array be 'roof-mounted on one- or two-family dwelling or accessory structure'. 85% · ordinance
• Is there a local rule on service upgrades or busbar sizing? Yes, a service-panel rule: County Code 6.3-23 amends California Electrical Code Section 230.79(C) to add 'All new single family dwellings in excess of fifteen hundred square feet of living area will be equipped with minimum two hundred amp main service panels.' That is a new-construction rule, so it does not by itself force a service upgrade on a retrofit - but it means most newer Solano houses already present a 200 A service. There is no local busbar rule; busbar sizing is handled by CEC 705.12(D)(2)(3)(b) and the Guidebook's eligibility gate that the system interconnect to a single-phase 120/220 V panel with a bus bar rating of 225 A or less. 85% · ordinance
• Is a specific mounting system or attachment spacing required? No county-mandated brand or product, but the adopted Structural Criteria fixes the geometry for the expedited path: modules flush and parallel to the roof plane; a 2 to 10 inch gap between the underside of the module and the roof surface; no overhang of ridges, hips, gable ends or eaves; modules plus supports no more than 4 psf (5 psf for solar thermal); array covering no more than half the total roof area across all planes; anchor horizontal spacing at or below the Table 1 value for the measured roof slope and rafter spacing (16, 24 or 32 inches o.c.); and anchor fasteners that are either 5/16 inch diameter lag screws with 2.5 inch embedment into the rafter, or compliant with the manufacturer's guidelines. Racking manufacturer worksheets, tables with relevant cells circled, or web-calculator output must be attached. Miss any of it and a California-licensed civil or structural engineer must stamp project-specific drawings and calculations. A single roof with no reroof overlay is also required. 85% · adopted checklist

Booking is a portal, a phone call or an email depending on the authority, and the notice required is rarely zero. Book before the work is finished rather than after — the lead time, not the work, is usually what sets the date.

• How is an inspection booked? Phone is the published route: 'To request a building inspection, call the 24-hour building inspection request line: (707) 784-4750.' The Accela portal also carries a 'Schedule an Inspection' function, so both work, but the county's Inspections page names only the phone line. The message must give the building permit number, job site address, the type of inspection requested and a callback number. 85% · department page
• How much notice is required? Effectively one business day. 'Requests received before 3:00pm will be scheduled for the following business day and all calls received after 3:00pm will be scheduled 2 business days later.' The request line takes messages 24 hours a day, so the 3 p.m. cutoff is the only constraint. 90% · department page
• Are same-day or AM/PM windows offered? No. 'We cannot make appointments for a specific time of day.' No AM/PM window and no same-day service is offered - the earliest is next business day for a pre-3 p.m. request. The county does publish a Daily Inspection Schedule, 'updated every morning', as an Accela report, which is how you find out roughly when to expect the inspector. 90% · department page

Some authorities inspect their own solar work; some delegate it, and a few do not inspect the PV equipment itself at all. Who is coming determines what they will look at.

• Does this AHJ perform its own final solar inspection? Yes. Building & Safety Services performs its own inspections - 'Inspects construction to make sure it is safe and code-compliant' - and County Code 6.3-16.030(d) provides that for expedited small residential rooftop solar 'Only one (1) timely inspection shall be required and performed by staff... excepting a separate fire inspection if necessary.' The roof-mount PV fee is priced on exactly 1 inspection. 90% · ordinance
• If delegated, to whom? Not delegated. The one carve-out in the ordinance is fire: 6.3-16.030(d) allows 'a separate fire inspection if necessary', and fire-code enforcement in unincorporated Solano sits with the independent fire protection districts - Cordelia, Dixon, Montezuma, Suisun and Vacaville under the Consensus Fire Ordinance, plus Fairfield Fire Department and East Vallejo Fire Protection District, which the county's AB 2234 page lists as agencies that 'may require reviews of plans or the payment of fees prior to Solano County issuing the permit'. Note the wrinkle: County Code 6.3-02(d) defines the 'fire official' for the Fire Code as adopted in Chapter 6.3 to mean the building official of Solano County, so the two roles overlap on paper. 70% · department page

A rough-in or mid-roof inspection, where one is required, has to happen before the work it covers is closed up. Missing a stage means opening something back up, and it is the most expensive kind of correction.

• Which inspections are required, and in what order? One. For an expedited small residential rooftop system the ordinance guarantees a single inspection: 'Only one (1) timely inspection shall be required and performed by staff for small residential rooftop solar energy systems eligible for expedited review, excepting a separate fire inspection if necessary. If the system fails inspection, a subsequent inspection is authorized but need not conform to the requirements of this section.' The fee schedule prices roof-mount PV on 1 inspection and ground-mount on 3. For anything else the sequence is not published online - the Inspections page says 'Please follow the back of the building permit job card for the sequence of inspections', and the permit card is delivered by the inspector at the first inspection and 'is not available online'. 80% · ordinance
• Is a rough-in or mid-roof inspection required? No, not for an expedited rooftop system - the ordinance allows only one inspection, so there is no rough-in or mid-roof stage. That does not extend to a ground-mount (priced on 3 inspections) or to a system that loses expedited eligibility by including battery storage. The general rule of thumb the county publishes still applies to anything staged: 'Don't cover it until the inspector sees it.' 75% · ordinance

The approved plan set, the permit, and the equipment listings should be on site and reachable. Inspectors routinely verify that installed equipment matches what was approved, and that the labels are the ones the plan set promised.

• Is there a published inspection checklist? The county publishes none of its own - but it does publish one by adoption. Building & Safety Services' Documents page carries six items (Sample Site Plan, EV Charging Stations Checklist, Agent Authorization Form, Permit Extension Request, California Solar Permitting Guidebook, Special Inspection & Testing Agreement) and the Inspections page has no checklist; the only inspection checklist reachable from county pages is the one inside the Guidebook it hosts (Part 3, section 5). Notably the county DOES publish a bespoke residential EV-charger checklist but no bespoke solar one. 75% · department page
• What must be on site at inspection? The approved plans and the permit, plus a posted address. 'The approved set of plans and the building permit must be available to the inspector at the time of inspection. No inspection can be conducted without the plans and permit on site.' 'In most cases the building inspector will deliver the permit card at the first inspection. The permit card is not available online.' 'Please keep the approved set of drawings on site. In most cases, the approved drawings shall be downloaded and printed by the applicant.' 'The site address must be clearly posted prior to any inspection.' The Guidebook adds that permit holders 'must be prepared to show conformance with all technical requirements in the field', which in practice means equipment spec sheets. 90% · department page
• Does the inspector verify labels and listings? Yes. The inspection checklist in the Guidebook the county adopts lists, among the common checks: 'Number of PV modules and model number match plans and specification sheets'; 'Appropriate signs are properly constructed, installed and displayed, including... Sign identifying PV power source system attributes at DC disconnect, Sign identifying AC point of connection, Sign identifying switch for alternative power system'; and 'Equipment ratings are consistent with application and installed signs on the installation' - inverter rating against the max voltage on the PV power source sign, DC-side OCPD ratings, inverter AC voltage against the AC point of connection sign, the 125% OCPD rule and the 120% busbar rule. 'The inspector will verify that the installation is in conformance with applicable code requirements and with the approved plans.' 75% · adopted checklist

Passing gives you a final or an equivalent sign-off. That is not the same as permission to operate: PTO comes from the utility, and who tells the utility the inspection passed varies. A system left switched off for weeks is usually waiting on this handover.

• What is issued on pass? Final - a passed final inspection on the permit, recorded against the Accela record; the physical evidence is the signed job card the inspector delivers at first inspection. A Certificate of Occupancy is NOT issued for a solar retrofit: County Code 6.3-17 attaches the CO to using or occupying a building or structure, and 6.3-18 defines final inspection for a dwelling as coming 'after final grading and the building is completed and ready for occupancy'. Neither describes a PV permit, which finals on its own. The document PG&E then wants is 'a copy of the final building permit'. 75% · ordinance
• Who notifies the utility for PTO? Installer. PG&E: 'To get permission to operate your system, your contractor submits all required paperwork to PG&E. The paperwork includes: The Interconnection Application, A single line diagram of the system, A copy of the final building permit. After PG&E approves the documents, we'll upgrade your meter and send you official written permission to operate.' Solano County does not notify PG&E - the county's role ends at the final inspection, and the contractor carries the county's sign-off across. Timeline: 'permission to operate your system typically takes 5 to 10 business days, up to a maximum of 30 business days' after PG&E has the paperwork, faster by email if an email address is on the application. MCE has no role in PTO. 90% · utility process page
• Is there a re-inspection fee? $194 (FY2026/27 recommended; $184 previously) - the schedule's 'Net Per Trip & Reinspection Fee', which equals the hourly service rate with a one-hour minimum. The same rate is what applies when a permit needs more inspections than its fee covers: 'Inspections exceeding the number of units included in fees will be charged at an hourly rate with a minimum of one hour per inspection service.' Since a roof-mount PV fee buys exactly 1 inspection, a second visit is a chargeable event. Separately, County Code 6.3-16.030(d) provides that if an expedited system fails, 'a subsequent inspection is authorized but need not conform to the requirements of this section'. 75% · fee schedule
• How are corrections issued and cleared? Not published for building inspections. There is a published incentive on the county's side - 'Pursuant to California Government Code Section 17951(d), the permittee may be entitled to reimbursement of permit fees in the event that Solano County fails to conduct a final inspection within 60 days of receiving notice by the permittee' - and the parallel EV-charging ordinance describes a written correction notice at PLAN stage ('the building official shall issue a written correction notice to the applicant detailing all deficiencies'), but nothing states how field corrections are issued or cleared for a solar job. 40% · department page