City of Lathrop (CA)

California Authority Having Jurisdiction Solar permitting requirements

NEC Code Version2023

Fire Code Version2018 Building Code

SolarAPP+ StatusAdopted

Wet Stamps RequiredDigital Structural

Fire Setback Enforced1

Codes

NEC Code Version: 2023

Fire Code Version: 2018 Building Code

Code List

2025 CALIFORNIA BUILDING CODE

2025 CALIFORNIA ELECTRICAL CODE

2025 CALIFORNIA FIRE CODE

2025 CALIFORNIA PLUMBING CODE

2025 CALIFORNIA MECHANICAL CODE

2025 CALIFORNIA ENERGY CODE

2025 CALIFORNIA RESIDENTIAL CODE

2025 CALIFORNIA ADMINISTRATIVE CODE

ASCE Code Specification: ASCE 7-16

SolarAPP+ & submittal

SolarAPP+ Status: Adopted

Date SolarAPP+ Accepted: 45131

Any SolarAPP+ Restrictions: 1

SolarAPP+ Restriction Notes: MAX SolarAPP size allowed is 10kw

SolarAPP+ Restrictions: Existing Systems,Trenching,MPU,Derate,Other

How Many Plansets Required: 1

Revision Required: 1

Rough Inspection: None

New Planset Required For Module Swap: 1

Stamps

Ee Stamp Required On SLD: No

Wet Stamps Required: Digital Structural

Structural Calculations Required: Yes

Stamp Location On Plans: Unspecified

Date On Stamps: Expiration Date

Fire setbacks

Fire Setback Enforced: 1

Setback Notes: * **R324.6.2 Setback at ridge:** For photovoltaic arrays occupying not more than 33 percent of the plan view total roof area, not less than an 18-inch clear set back is required on both sides of a horizontal ridge. For photovoltaic arrays occupying more than 33 percent of the plan view total roof area, not less than a 36inch clear set back is required on both sides of a horizontal ridge. * Existing arrays on the home count toward the 33% of roof coverage and must be accounted for when determining 18 or 36 inch setbacks at the ridge.

Structural & loads

Wind Speed: 95

Wind Notes: Exposure Category B

Snow Load: 0

Reducible Snow Load Allowed: 1

Max Attachment Spacing: 96

Structural Notes: Standard

Minimum Ground On Roof: #10

Electrical

Electrical Load Calcs Required: Derates

Allowed POI: Load Side Taps,PV Breaker,Meter Adapter,Line Side Taps

Panel Schedule Required: Partial Home Backup

Temperature Rating: 90

De Rating Ampacity: 0.96

Battery / ESS

Unique Battery Placards Needed: 0

ESS Notes

Include this note on ELD: Producer's storage device(s) will not cause the Host Load to exceed its normal peak demand. Normal peak demand is defined as the highest amount of power required from the Distribution System by Producer's complete facilities without the influence or use of the energy storage device(s).

Show a JB if required.

Please provide disconnecting means for the Battery.

If the disconnecting means is internal to the unit, please show it complies with CEC 705.20.

Provide a label on the ESS disconnect that includes the following: Nominal ESS AC voltage and maximum ESS DC Voltage. CEC 480.7(D), 706.15.

Do not waste one-quarter of the placard real estate with “CAUTION” and “POWER TO THIS BUILDING IS ALSO…”; this language is not code required.

The language required by CEC 705.10: “Caution Multiple Sources of Power”.

Identify ALL power source disconnect locations.

If the placard depicts a map of the building and site, provide a North arrow or compass rose. Make sure North is UP.

Show the location of driveways and relevant fences and gates. Show the address and street location.

Do not clutter the diagram with items irrelevant to the shutdown process. Make sure there is separation between items in the depiction. Do not let locations blob on top of each other.

Please provide a clear diagram that will quickly and accurately identify to firefighters the power sources and steps for emergency electrical shutdown initiation method since opening the utility service disconnect may not cause a complete shutdown.

E.g. (example only): POWER TO THIS BUILDING IS SUPPLIED FROM 3 SOURCES: UTILTY, ESS (battery), and PV SOLAR Two steps for Complete SHUTDOWN - 1. OPEN MAIN BREAKER in MAIN PANEL 2. TURN OFF E-stop switch labeled ESS

Make sure the ESS remote switch is marked “ESS” on its face and on the placard. Include the placard and its posted locations on the label sheet. The placard must posted at the electrical service and at ALL power production source disconnects. CEC 705.10

ESS DESIGN

Add ESS mounting details

Separate ESS Disconnect Required: ESS Disconnect

ESS Elevation Detail Required: No

Plan set

Plan Set Requirements

Production meter required. (ONLY IF UTILITY IS LATHROP AS WELL NOT FOR PG&E)
Inverter -> Production Meter -> Disco -> MSP
complete standard plan below for expedited permitting
Include the SDS (design spectral response) on the plans. To find the SDS and SD1, their structural reviewer sent this link https://hazards.atcouncil.org/ Standard Jobs
On the plans, please specify the structural design criteria required per CBC 1603.1: wind and seismic design criteria.
Plan pages not being signed/sealed by the structural engineer must contain the license holder's signature or the designer's signature. This includes the electrical pages, photos of existing electrical equipment pages, and the label/placard pages. Pages only for install use and spec sheets do not need signature.

Existing Systems

Note the complete kWdc rating for the existing and new systems on the cover sheet.
Note on the cover sheet the size of the existing solar system.

Cover Page

Indicate building data on the title sheet:

Type of Construction for the building
Occupancy classification
Square footage of arrays. (Include the existing)
Percentage of roof covers by the arrays. (Include the existing panels)
If the building is sprinklered or not.

Cover Page Notes: All Jobs [Contractor is to verify the dwelling unit's smoke and carbon monoxide alarms per CRC sections R314 and R315, prior to the final inspection.]

Roof Plan

ALL PROJECTS:

Indicate on plans the point of access to the fire pathways on the front and back of the house.
Provide wind speed and seismic design criteria

Existing systems:

For buildings that have PV systems with both rapid shutdown types or a PV system with a rapid shutdown type and a PV system with no rapid shutdown, a detailed plan view diagram of the roof shall be provided showing each different PV system and a dotted line around areas that remain energized after the rapid shutdown switch is operated.

Roof Plan Notes: All Jobs [The point of access will not be over any doors, windows, or other obstructions.]

Attachment Detail

Specify the lag screws edge distance (laterally loaded and withdrawal)
The AHJ strictly follows the 4D rule for Lag diameter. Ex. a 2x4 must not have a lag larger than 1/4 in diameter.
Provide span tables showing the required spacing of anchors at different roof zones.

Electrical Diagram: Clarify the grounding electrode conductor shall be sized per CEC 250.66. Show that the PV breaker shall be located at the opposite end of the busbar from the primary power source

Electrical Diagram Notes: All Jobs [All equipment shall be listed and labeled by a Nationally Recognized Testing Laboratory (NRTL) // The PV breaker shall be located at the opposite end of the busbar from the primary power source // New electrical shall be located at least three (3) feet from gas meter or gas shut-off valves. CPC1208.7.1; CEC 110.26 // The wire size and type of the service feeding conductor for the main service panel shall be determined by the utility provider. // Grounding electrode conductor shall be sized per CEC 250.66] Existing Systems [The new PV system has equal or greater AIC rating to the existing electrical system. CEC 690.13(E) // Both the new and existing solar breakers are located at the opposite end of the busbar from the primary power source.]

Label Page

The “Warning Photovoltaic Power Source” label(s) should be placed only on conduit and enclosures containing always-energized DC conductors per CEC 690.31(G)(3), not on conduits/enclosures containing AC conductors.
IE: If project is a microinverter system, there will be no such conduit or enclosures, so remove the label from the plan sheet.
Required placard: "CAUTION: MULTIPLE SOURCES OF POWER".

Existing systems:

For buildings that have PV systems with both rapid shutdown types or a PV system with a rapid shutdown type and a PV system with no rapid shutdown, a detailed plan view diagram of the roof shall be provided showing each different PV system and a dotted line around areas that remain energized after the rapid shutdown switch is operated.

Custom Placards Required: 1

Ground mount

Ground Mount Fencing Required: Mesh/Scrim

Ground Mount Notes

8/1/24 - scrim is allowed per AHJ in lieu of fence

5/16/24 - Nuance DQ in this area due to third party inspector requirement

Provide 48-inch-high fence, wall or other barrier that isolates the GM system from access to the public. **Enclosure Requirements:** See attachment (GM fence requirements) 1\. The top of the enclosure shall be at least 48 inches above the grade. the maximum vertical clearance between the grade and the bottom of the enclosed fence/wall/barrier shall be 2inches. 2\. The horizontal distance from the enclosure to the GM and all other equipment inside the enclosure shall be a minimum of 36 inches. 3\. Maximum mesh size for chain link fences shall be 1-1/2 inch square, unless the fence has slats fastened at the top or the bottom which reduce the openings to not more than 1-3/4 inches. 4\. Access gates shall be equipped to accommodate a locking device. Show the PV Solar rail system and module frames are bonded to ground, typically with a bare Cu EGC, minimum #6 AWG unless protected. Please show details of attachment of the electrical enclosures to the ground mount structure. Show that any exposed PVC conduit at the structure or building subject to damage is schedule 80. GM requirements are on a lot by lot basis. Reach out to Assistant Planner TRENT DADALT to find out the setback requirements and other standards at or _