CRC · California Residential Code
Where should DC conductors, combiner boxes and pathways be located on PV roofs?
For homeowners: DC wiring for rooftop solar should be routed near roof ridges, hips or valleys and run straight to an outside wall, with combiner boxes placed to keep conduit out of required 36‑inch firefighter pathways and to minimize roof conduit length; wiring in enclosed spaces must be in metallic conduit. Key rules are in the California Residential Code at **§ R329.8.3** and the pathway/setback rules in **R329.6.1 – R329.6.2**.
Last reviewed: July 6, 2026
What the code requires — 2-4 sentences
The California Residential Code requires that DC conductors and conduit be routed so they are as close as possible to the ridge, hip or valley and run as directly as possible from those high/low roof lines to an outside wall; DC combiner boxes must be sited to minimize conduit on roof pathways and between sub‑arrays. This routing intent and the metallic conduit requirement for enclosed spaces are stated in § R329.8.3.
Keep conductors out of the middle of firefighter access routes: run conduit along ridges/hips/valleys toward an outside wall and place combiner boxes to shorten roof runs. (Plain‑English restatement of § R329.8.3.)
Requirements in detail
Key rules (plain list)
- Route PV conduit and raceways as close as possible to the ridge, hip or valley, and run from those roof features directly to an outside wall to reduce trip hazards and maximize ventilation — § R329.8.3.
- Install conduit runs between sub‑arrays and to DC combiner boxes so as to minimize total conduit on the roof — take the shortest path from array to combiner box — § R329.8.3.
- Locate DC combiner boxes so conduit runs are minimized in the pathways between arrays (i.e., avoid placing combiner boxes inside required access/ventilation pathways) — § R329.8.3.
- Where PV DC wiring is located within enclosed spaces in a building, it must be installed in metallic conduit or raceways — § R329.8.3.
- Conduit should run along the bottom of load‑bearing members where it passes along structural members — § R329.8.3.
Note: The CRC contains pathway and setback dimensions for rooftop arrays in R329.6 (pathways, ridge setbacks). Where similar requirements are stated for non‑residential occupancies, the California Fire Code also repeats the DC conductor location guidance (see the related provisions).
Decision table — decision‑relevant dimensions / values
| What you need to size or locate | Code value / threshold | Code Reference |
|---|---|---|
| Minimum roof pathway width from lowest edge to ridge (per roof plane with array) | 36 in (914 mm) | § R329.6.1 |
| Ridge setback when PV ≤ 33% of roof area | 18 in (457 mm) each side of horizontal ridge | § R329.6.2 |
| Ridge setback when PV > 33% of roof area | 36 in (914 mm) each side of horizontal ridge | § R329.6.2 |
| Alternative ridge setbacks with interior sprinklers (up to specified PV% thresholds) | 18 in / 36 in variants per § R329.6.2.1 | § R329.6.2.1 |
| Perimeter pathway (Fire Code, other occupancies) | 6 ft (1829 mm) clear perimeter; may reduce to 4 ft (1219 mm) for smaller buildings | 1205.3.1 (CFC) |
| Interior pathways and smoke ventilation options (other occupancies) | 4 ft (1219 mm) min interior pathways; smoke vent options include 8 ft clear pathway or 4 ft + vent cutouts | 1205.3.2 – 1205.3.3 (CFC) |
| Location of DC conductors / conduit routing | As close as possible to ridge/hip/valley; direct to outside wall; minimize conduit on roof | § R329.8.3 |
(Where the Fire Code provides more detailed pathway widths for non‑R‑3 occupancies, those numeric pathway rules are in Sections 1205.3.x.)
Practical application of the language in § R329.8.3
- "As close as possible to the ridge or hip or valley" — route main DC trunklines near those roof lines so they do not cross the middle of required pathways. § R329.8.3 requires that proximity.
- "Shortest path from the array to the DC combiner box" — when planning combiner box location, choose the position that yields the least roof conduit length while staying out of required pathways. § R329.8.3.
- "DC wiring shall be installed in metallic conduit or raceways when located within enclosed spaces in a building" — if routing goes through soffits, attics or enclosed chase spaces on‑site, use metallic conduit or approved raceways. § R329.8.3.
Exceptions & special cases
- Building‑integrated PV (BIPV): Where BIPV creates hidden electrical hazard areas, reflective markings to identify hazardous ladder placement areas are required; and UL‑listed BIPV per UL 3741 may be treated differently. See § R329.6.4 and R329.5.
- Roof slope exception: The roof access/pathway requirements in R329.6 do not apply to roofs with slopes of 2 in 12 (≈16.7%) or less. (CRC exception under R329.6.)
- Fire code differences for non‑R‑3 buildings: The California Fire Code contains parallel (and sometimes additional) pathway and DC conductor location language (e.g., 1205.2.4 / 1205.3.4) that applies for non‑residential occupancies; where jurisdictions enforce both, follow the authority having jurisdiction.
- Combiner box in the pathway: The code intent is to minimize combiner boxes inside pathways; if a combiner box must be in a pathway, coordinate with the enforcing agency/fire code official — the CRC text requires minimizing conduit in pathways but does not list a specific prohibition for minor equipment in every circumstance. § R329.8.3.
If you need the exact text of § R329.6.3, I could not locate R329.6.3 in the CRC excerpts returned by the files I searched. The pathway/setback specifics are in R329.6.1 and R329.6.2, which are available in the retrieved CRC.
Common mistakes
- Routing long runs of conduit across the middle of required 36 in (914 mm) pathways instead of along the ridge/hip/valley — violates the routing intent in § R329.8.3 and may block firefighter access under R329.6.1.
- Placing DC combiner boxes in a pathway without checking whether a shorter route (e.g., toward an eave/hip) would keep the box out of the pathway — § R329.8.3 requires minimizing conduit in pathways.
- Using non‑metallic conduit in enclosed attic/chase spaces when metallic conduit is required by § R329.8.3.
- Ignoring ridge setbacks (18 in / 36 in) and not providing the required pathway to the ridge — see § R329.6.2 and R329.6.1.
Worked example — concrete scenario applying the rule with numbers
Scenario: a one‑story single‑family dwelling (R‑3) with two sub‑arrays on the same roof plane. Each array is set so PV occupies 25% of the plan‑view roof area (≤33% threshold). The designer must provide required pathways and route DC conduit and combiner boxes.
Steps to comply:
- Pathways: Provide at least two pathways from lowest roof edge to ridge on separate roof planes or at least one on street/driveway side; each pathway must be 36 in (914 mm) wide — § R329.6.1.
- Ridge setback: Because PV ≤ 33%, keep a 18 in (457 mm) clear setback on both sides of the horizontal ridge — § R329.6.2.
- Conduit routing: Route the DC trunklines adjacent to the ridge or hip and run from the ridge as directly as possible to the outside wall — § R329.8.3. Example: if the array center is 20 ft from the outside wall and 5 ft from the ridge, route the conductor within 1–2 ft of the ridge toward the outside wall to keep run lengths short and avoid crossing the 36 in access pathway. § R329.8.3.
- Combiner box placement: Place the DC combiner box at or near a hip/valley/edge so each sub‑array’s conduit to the combiner box is the shortest practical run and not across the required 36 in pathway. If one placement reduces total roof conduit by 30 ft compared to another location that crosses a pathway, select the shorter routing consistent with § R329.8.3.
- Enclosed spaces: If any part of the DC routing must pass through an attic or enclosed chase, use metallic conduit or raceways for that portion — § R329.8.3.
Takeaway: design the array layout so the mount location + combiner box location keep conduit runs close to ridges/hips/valleys and away from the center of required 36‑inch pathways and ridge setbacks.
Related provisions
- § R329.8.3 — Locations of DC conductors (CRC).
- § R329.6.1 — Minimum roof pathways (36 in) and routing intent (CRC).
- § R329.6.2 — Ridge setbacks (18 in / 36 in) (CRC).
- § R329.6.4 — BIPV marking requirements for hidden hazards (CRC).
- 1205.2.4 / 1205.3.4 — Locations of DC conductors and related routing language in the California Fire Code (for occupancies other than R‑3).
- R329.4.1.1 / R329.4.1.2 — Roof loads and wind loads for PV support (for siting considerations).
Code references
Grounded in the retrieved California Residential Code — click a citation to read the verbatim passage:
CRC § 8.1 High relevance — show source text
R329.8 Ground-mounted photovoltaic (PV) panel systems. Ground-mounted photovoltaic (PV) panel systems shall be designed and installed in accordance with Section R301.
R329.8.1 Fire separation distances. Ground-mounted photovoltaic systems shall be subject to the fire separation distance requirements determined by the enforcing agency.
R329.8.2 Ground-mounted photovoltaic arrays. Ground mounted photovoltaic arrays shall comply with this section and the Cali- fornia Electrical Code. Setback requirements shall not apply to ground-mounted, free-standing photovoltaic arrays. A clear, brush- free area of 10 feet (3048 mm) shall be required for ground-mounted photovoltaic arrays.
R329.8.3 Locations of DC conductors. Conduit, wiring systems and raceways for photovoltaic circuits shall be located as close as possible to the ridge or hip or valley and from the hip or valley as directly as possible to an outside wall to reduce trip hazards and maximize ventilation opportunities. Conduit runs between sub arrays and to DC combiner boxes shall be installed in a manner that minimizes the total amount of conduit on the roof by taking the shortest path from the array to the DC combiner box. The DC combiner boxes shall be located such that conduit runs are minimized in the pathways between arrays. DC wiring shall be installed in metallic conduit or raceways when located within enclosed spaces in a building. Conduit shall run along the bottom of load bearing members.
SECTION R330—ENERGY STORAGE SYSTEMS
R330.1 General. Energy storage systems (ESS) shall comply with the provisions of this section.
Exceptions:
- ESS listed and labeled for use in habitable spaces, in accordance with UL 9540 and where installed in accordance with the listing, the manufacturer’s instructions and the California Electrical Code.
- ESS less than 1 kWh (3.6 megajoules).
R330.2 Equipment listings. Energy storage systems (ESS) shall be listed and labeled in accordance with UL 9540.
Exception: Where approved, repurposed unlisted battery systems from electric vehicles are allowed to be installed outdoors or in detached sheds located not less than 5 feet (1524 mm) from exterior walls, property lines and public ways.
R330.3 Installation. ESS shall be installed in accordance with the manufacturer’s instructions and their listing.
R330.3.1 Spacing. Individual units shall be separated from each other by not less than 3 feet (914 mm) except where other separation distances are specified by the ESS listing and the manufacturer’s installation instructions.
R330.4 Locations. ESS shall be installed only in the following locations:
- Detached garages and detached accessory structures.
- Attached garages separated from the dwelling unit living space in accordance with Section R302.6.
- Outdoors or on the exterior side of exterior walls located not less than 3 feet (914 mm) from doors and windows directly entering the dwelling unit, except where smaller separation distances are permitted by the UL 9540 listing and manufacturer’s installation instructions.
CRC § 3.1. High relevance — show source text
- Smoke ventilation options between array sections shall be one of the following: 3.1. A pathway not less than 8 feet (2438 mm) wide. 3.2. A pathway not less than 4 feet (1219 mm) wide bordering 4-foot by 8-foot (1219 mm by 2438 mm) venting cutouts every 20 feet (6096 mm) on alternating sides of the pathway.
1205.3.4 Locations of DC conductors in occupancies other than R-3. Conduit, wiring systems and raceways for photovoltaic circuits shall be located as close as possible to the ridge or hip or valley and from the hip or valley as directly as possible to an outside wall to reduce trip hazards and maximize ventilation opportunities. Conduit runs between sub arrays and to DC combiner boxes shall be installed in a manner that minimizes the total amount of conduit on the roof by taking the shortest path from the array to the DC combiner box. The DC combiner boxes shall be located such that conduit runs are minimized in the pathways between arrays. DC wiring shall be installed in metallic conduit or raceways when located within enclosed spaces in a building. Conduit shall run along the bottom of load bearing members.
1205.4 Buildings with rapid shutdown. Buildings with rapid shutdown solar photovoltaic systems shall have permanent labels in accordance with Sections 1205.4.1 through 1205.4.3.
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ENERGY SYSTEMS
1205.4.1 Rapid shutdown type. The type of solar photovoltaic system rapid shutdown shall be labeled with one of the following:
- For solar photovoltaic systems that shut down the array and the conductors leaving the array, a label shall be provided. The first two lines of the label shall be uppercase characters with a minimum height of [3] / 8 inch (10 mm) in black on a yellow background. The remaining characters shall be uppercase with a minimum height of [3] / 16 inch (5 mm) in black on a white background. The label shall be in accordance with Figure 1205.4.1(1) and state the following:
SOLAR PV SYSTEM EQUIPPED WITH RAPID SHUTDOWN. TURN RAPID
SHUTDOWN SWITCH TO THE “OFF”
POSITION TO SHUT DOWN PV SYSTEM
AND REDUCE SHOCK HAZARD IN ARRAY.
- For photovoltaic systems that only shut down conductors leaving the array, a label shall be provided. The first two lines of the label shall be uppercase characters with a minimum height of [3] / 8 inch (10 mm) in white on a red background and the remaining characters shall be capitalized with a minimum height of [3] / 16 inch (5 mm) in black on a white background. The label shall be in accordance with Figure 1205.4.1(2) and state the following:
THIS SOLAR PV SYSTEM EQUIPPED WITH RAPID SHUTDOWN. TURN RAPID
SHUTDOWN SWITCH TO THE “OFF”
POSITION TO SHUT DOWN CONDUCTORS
OUTSIDE THE ARRAY. CONDUCTORS
WITHIN ARRAY REMAIN ENERGIZED IN SUNLIGHT.
FIGURE 1205.4.1(1)—LABEL FOR SOLAR PV SYSTEMS THAT REDUCE
SHOCK HAZARD WITHIN ARRAY AND SHUT DOWN CONDUCTORS LEAVING ARRAY
CRC § 1205.2.3 High relevance — show source text
1205.2.3 Building-integrated photovoltaic (BIPV) systems. Where building-integrated photovoltaic (BIPV) systems are installed in a manner that creates areas with electrical hazards to be hidden from view, markings shall be provided to identify the hazardous areas to avoid for ladder placement. The markings shall be reflective and be visible from grade beneath the eaves or other location approved by the fire code official.
Exception: BIPV systems listed in accordance with UL 3741, where the removal or cutting away of portions of the BIPV system during firefighting operations have been determined to not expose a firefighter to electrical shock hazards.
1205.2.4 Locations of DC conductors. Conduit, wiring systems and raceways for photovoltaic circuits shall be located as close as possible to the ridge or hip or valley and from the hip or valley as directly as possible to an outside wall to reduce trip hazards and maximize ventila- tion opportunities. Conduit runs between sub arrays and to DC combiner boxes shall be installed in a manner that minimizes the total amount of conduit on the roof by taking the shortest path from the array to the DC combiner box. The DC combiner boxes shall be located such that conduit runs are minimized in the pathways between arrays. DC wiring shall be installed in metallic conduit or raceways when located within enclosed spaces in a building. Conduit shall run along the bottom of load bearing members.
1205.3 Other than Group R-3 buildings. Access to systems for buildings, other than those containing Group R-3 occupancies, shall be provided in accordance with Sections 1205.3.1 through 1205.3.3.
Exception: Where it is determined by the fire code official that the roof configuration is similar to that of a Group R-3 occupancy, the residential access and ventilation requirements in Sections 1205.2.1.1 through 1205.2.1.3 are a suitable alternative.
1205.3.1 Perimeter pathways. There shall be a minimum 6-foot-wide (1829 mm) clear perimeter around the edges of the roof.
Exception: Where either axis of the building is 250 feet (76 200 mm) or less, the clear perimeter around the edges of the roof shall be permitted to be reduced to a minimum width of 4 feet (1219 mm).
1205.3.2 Interior pathways. Interior pathways shall be provided between array sections to meet the following requirements:
- Pathways shall be provided at intervals not greater than 150 feet (45 720 mm) throughout the length and width of the roof.
- A pathway not less than 4 feet (1219 mm) wide in a straight line to roof standpipes or ventilation hatches.
- A pathway not less than 4 feet (1219 mm) wide around roof access hatches, with not fewer than one such pathway to a parapet or roof edge.
1205.3.3 Smoke ventilation. The solar installation shall be designed to meet the following requirements:
- Where nongravity-operated smoke and heat vents occur, a pathway not less than 4 feet (1219 mm) wide shall be provided bordering all sides.
- Where gravity-operated dropout smoke and heat vents occur, a pathway not less than 4 feet (1219 mm) wide on not fewer than one side.
CRC § 12-6 High relevance — show source text
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ENERGY SYSTEMS
1205.2.1.2 Setbacks at ridge. For photovoltaic arrays occupying 33 percent or less of the plan view total roof area, a setback of not less than 18 inches (457 mm) wide is required on both sides of a horizontal ridge. For photovoltaic arrays occupying more than 33 percent of the plan view total roof area, a setback of not less than 36 inches (457 mm) wide is required on both sides of a horizontal ridge.
1205.2.1.3 Alternative setbacks at ridge. Where an automatic sprinkler system is installed within the dwelling in accordance with Section 903.3.1.3, setbacks at the ridge shall conform to one of the following:
- For photovoltaic arrays occupying 66 percent or less of the plan view total roof area, a setback of not less than 18 inches (457 mm) wide is required on both sides of a horizontal ridge.
- For photovoltaic arrays occupying more than 66 percent of the plan view total roof area, a setback of not less than 36 inches (914 mm) wide is required on both sides of a horizontal ridge.
1205.2.2 Emergency escape and rescue openings. Panels and modules installed on Group R-3 buildings shall not be placed on the portion of a roof that is below an emergency escape and rescue opening. A pathway of not less than 36 inches (914 mm) wide shall be provided to the emergency escape and rescue opening.
1205.2.3 Building-integrated photovoltaic (BIPV) systems. Where building-integrated photovoltaic (BIPV) systems are installed in a manner that creates areas with electrical hazards to be hidden from view, markings shall be provided to identify the hazardous areas to avoid for ladder placement. The markings shall be reflective and be visible from grade beneath the eaves or other location approved by the fire code official.
Exception: BIPV systems listed in accordance with UL 3741, where the removal or cutting away of portions of the BIPV system during firefighting operations have been determined to not expose a firefighter to electrical shock hazards.
1205.2.4 Locations of DC conductors. Conduit, wiring systems and raceways for photovoltaic circuits shall be located as close as possible to the ridge or hip or valley and from the hip or valley as directly as possible to an outside wall to reduce trip hazards and maximize ventila- tion opportunities. Conduit runs between sub arrays and to DC combiner boxes shall be installed in a manner that minimizes the total amount of conduit on the roof by taking the shortest path from the array to the DC combiner box. The DC combiner boxes shall be located such that conduit runs are minimized in the pathways between arrays. DC wiring shall be installed in metallic conduit or raceways when located within enclosed spaces in a building. Conduit shall run along the bottom of load bearing members.
1205.3 Other than Group R-3 buildings. Access to systems for buildings, other than those containing Group R-3 occupancies, shall be provided in accordance with Sections 1205.3.1 through 1205.3.3.
CRC § 3-75 High relevance — show source text
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BUILDING PLANNING
R329.6.4 Building-integrated photovoltaic (BIPV) systems. Where building-integrated photovoltaic (BIPV) systems are installed in a manner creating areas with electrical hazards that are hidden from view, markings shall be provided to identify the hazardous areas to avoid for ladder placement. The markings shall be reflective and be visible from grade beneath the eaves or other location approved by the fire code official.
Exception: BIPV systems listed in accordance with UL 3741, where the removal or cutting away of portions of the BIPV system during firefighting operations have been determined to not expose a firefighter to electrical shock hazards.
R329.7 Elevated photovoltaic (PV) support structures. Elevated PV support structures used as an accessory structure shall comply with either Section R329.7.1 or R329.7.2. Elevated PV support structures shall be considered a roof for the purposes of establishing the number of stories and fire separation distances.
Exception : Elevated PV support structures that are installed over agricultural use.
R329.7.1 PV panels installed over open-grid framing or noncombustible deck. Elevated PV support structures with PV panels installed over open-grid framing or over a noncombustible deck shall have PV panels tested, listed and labeled with a fire type rating in accordance with UL 1703 or with both UL 61730-1 and UL 61730-2. Photovoltaic panels marked “not fire rated” shall not be installed on elevated PV support structures.
R329.7.2 PV panels installed over a roof assembly. Elevated PV support structures with a PV panel system installed over a roof assembly shall have a fire classification in accordance with Section R902.4 and Section R329.4.
R329.8 Ground-mounted photovoltaic (PV) panel systems. Ground-mounted photovoltaic (PV) panel systems shall be designed and installed in accordance with Section R301.
R329.8.1 Fire separation distances. Ground-mounted photovoltaic systems shall be subject to the fire separation distance requirements determined by the enforcing agency.
R329.8.2 Ground-mounted photovoltaic arrays. Ground mounted photovoltaic arrays shall comply with this section and the Cali- fornia Electrical Code. Setback requirements shall not apply to ground-mounted, free-standing photovoltaic arrays. A clear, brush- free area of 10 feet (3048 mm) shall be required for ground-mounted photovoltaic arrays.
R329.8.3 Locations of DC conductors. Conduit, wiring systems and raceways for photovoltaic circuits shall be located as close as possible to the ridge or hip or valley and from the hip or valley as directly as possible to an outside wall to reduce trip hazards and maximize ventilation opportunities. Conduit runs between sub arrays and to DC combiner boxes shall be installed in a manner that minimizes the total amount of conduit on the roof by taking the shortest path from the array to the DC combiner box. The DC combiner boxes shall be located such that conduit runs are minimized in the pathways between arrays. DC wiring shall be installed in metallic conduit or raceways when located within enclosed spaces in a building. Conduit shall run along the bottom of load bearing members.
SECTION R330—ENERGY STORAGE SYSTEMS
CRC § 1205.2.1.1 High relevance — show source text
Exception: Where it is determined by the fire code official that the roof configuration is similar to that of a Group R-3 occupancy, the residential access and ventilation requirements in Sections 1205.2.1.1 through 1205.2.1.3 are a suitable alternative.
1205.3.1 Perimeter pathways. There shall be a minimum 6-foot-wide (1829 mm) clear perimeter around the edges of the roof.
Exception: Where either axis of the building is 250 feet (76 200 mm) or less, the clear perimeter around the edges of the roof shall be permitted to be reduced to a minimum width of 4 feet (1219 mm).
1205.3.2 Interior pathways. Interior pathways shall be provided between array sections to meet the following requirements:
- Pathways shall be provided at intervals not greater than 150 feet (45 720 mm) throughout the length and width of the roof.
- A pathway not less than 4 feet (1219 mm) wide in a straight line to roof standpipes or ventilation hatches.
- A pathway not less than 4 feet (1219 mm) wide around roof access hatches, with not fewer than one such pathway to a parapet or roof edge.
1205.3.3 Smoke ventilation. The solar installation shall be designed to meet the following requirements:
Where nongravity-operated smoke and heat vents occur, a pathway not less than 4 feet (1219 mm) wide shall be provided bordering all sides.
Where gravity-operated dropout smoke and heat vents occur, a pathway not less than 4 feet (1219 mm) wide on not fewer than one side.
Smoke ventilation options between array sections shall be one of the following: 3.1. A pathway not less than 8 feet (2438 mm) wide. 3.2. A pathway not less than 4 feet (1219 mm) wide bordering 4-foot by 8-foot (1219 mm by 2438 mm) venting cutouts every 20 feet (6096 mm) on alternating sides of the pathway.
1205.3.4 Locations of DC conductors in occupancies other than R-3. Conduit, wiring systems and raceways for photovoltaic circuits shall be located as close as possible to the ridge or hip or valley and from the hip or valley as directly as possible to an outside wall to reduce trip hazards and maximize ventilation opportunities. Conduit runs between sub arrays and to DC combiner boxes shall be installed in a manner that minimizes the total amount of conduit on the roof by taking the shortest path from the array to the DC combiner box. The DC combiner boxes shall be located such that conduit runs are minimized in the pathways between arrays. DC wiring shall be installed in metallic conduit or raceways when located within enclosed spaces in a building. Conduit shall run along the bottom of load bearing members.
1205.4 Buildings with rapid shutdown. Buildings with rapid shutdown solar photovoltaic systems shall have permanent labels in accordance with Sections 1205.4.1 through 1205.4.3.
2025 CALIFORNIA FIRE CODE 12-7
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ENERGY SYSTEMS
CRC § 1204.6 High relevance — show source text
1204.6 Cords and wiring. Extension cords and temporary wiring used to connect portable generators shall be in accordance with Section 603 and shall be provided with GFCI protection.
1204.7 Connections to premise wiring. Connections to a premise wiring system shall comply with all of the following:
Power shall not be provided in a manner that “back-feeds” receptacles or the premise wiring system.
Connection to a premise served by commercial power shall be made through a listed transfer switch installed, used and maintained in accordance with the California Electrical Code .
Connections to buildings not served by commercial power shall comply with the California Electrical Code .
1204.8 Refueling. Portable generators shall not be refueled while operating.
1204.9 Storage and repair. Storage and repair of fuel-fired portable generators shall comply with Section 313.
1204.10 Fire extinguisher. A listed portable fire extinguisher complying with Section 906 with a minimum rating of 2-A:20-B:C shall be provided not more than 50 feet (15 240 mm) from the portable generator.
SECTION 1205—SOLAR PHOTOVOLTAIC POWER SYSTEMS
1205.1 General. Solar photovoltaic (PV) systems shall be installed in accordance with the California Building Code or California Resi- dential Code . The electrical portion of solar PV systems shall be installed in accordance with the California Electrical Code . Rooftopmounted solar photovoltaic systems shall be installed in accordance with Sections 1205.2 through 1205.4.3. Ground-mounted solar photovoltaic systems shall comply with Section 1205.5.
1205.2 Access and pathways. Roof access, pathways and spacing requirements shall be provided in accordance with Sections 1205.2.1 through 1205.3.3. Pathways shall be over areas capable of supporting firefighters accessing the roof. Pathways shall be located in areas with minimal obstructions, such as vent pipes, conduit or mechanical equipment.
Exceptions:
- Detached, nonhabitable Group U structures including, but not limited to, detached garages serving Group R-3 buildings, parking shade structures, carports, solar trellises and similar structures.
- Roof access, pathways and spacing requirements need not be provided where the fire code official has determined that rooftop operations will not be employed.
- Building-integrated photovoltaic (BIPV) systems where the BIPV systems are approved, integrated into the finished roof surface and are listed in accordance with UL 3741. The removal or cutting away of portions of the BIPV system during firefighting operations shall not expose a firefighter to electrical shock hazards.
1205.2.1 Solar photovoltaic (PV) systems for Group R-3 buildings. Solar photovoltaic (PV) systems for Group R-3 buildings shall comply with Sections 1205.2.1.1 through 1205.2.3.
Exceptions:
These requirements shall not apply to structures designed and constructed in accordance with the California Residen- tial Code .
These requirements shall not apply to roofs with slopes of 2 units vertical in 12 units horizontal (16.7-percent slope) or less.
CRC § 2.2 Medium relevance — show source text
Design criteria R301.1, R301.2.2, R301.3
Service Utilities R111
Shakes
Wood R702.6, R703.6, R905.8 Shingle Asphalt shingles R905.2 Metal R905.4
Slate R905.6
Wood R905.7 Ship’s Ladders (see Ladders) R318.7.13 Shower R326.1, R327 Compartment R327.2 Finishes R327.2 Glazing R324.3.1, R324.4.5 Space required R327.1 Shutoff Valve (see Valves) Siding Exterior coverings R703 Sinks (see also Lavatories) R326.2 Site
Address R308
Preparation R408.5, R504.2, R506.3 Size
Of rooms R312 Skylights R324.6
Slate Shingles R905.6 Sleeping Lofts R315 Smoke Alarms R310
Smoke-Developed Index R302.10, R302.9 Snow Loads R301.1, Figure R301.2(3) Decks R507.1, R507.5, R507.6 Floors R502.3.3, R505.1.1 Foundation R403.1
Roof R301.6, R329.4.1.1, R802.10.2.1, R802.4.1, R804.3.2.1 Walls R602.3.1, R602.7, R603.3.2 Soffit R704
Fiber-cement R704.2.2, R704.3.2 Hardboard R704.2.3, R704.3.3 Vinyl R704.2.1, R704.3.1 Wood R704.2.4, R704.3.4 Solar Energy Systems R329 Building-integrated photovoltaic systems R329.5 Ground-mounted photovoltaic systems R329.8 Photovoltaic systems R329.3 Roof access and pathways R329.6 Rooftop-mounted photovoltaic systems R329.3 Sound Transmission Appendix BG Spans Steel (allowable) R505.3.2, R804.3.2.1 Wood (allowable) R502.3, R802.5 Sprinkler (see Automatic Sprinkler System) Stairways R318.7 Alternating tread devices R318.7.12 Bulkhead enclosure R318.7.11.2 Glazing R324.4.6 Guards R321
Handrails R318.7.8, R320 Headroom R318.7.2
Illumination R318.7.10, R325.6, R325.7 Landings for R318.7.6 Nosings R318.7.5.3 Ship’s ladders R318.7.13 Sleeping lofts R315.5.2 Spiral R318.7.11 Treads and risers R318.7.5, R318.7.5.4 Vertical egress R318.4 Vertical rise R318.7.3 Walking surface slope R318.7.7 Walkline R318.7.4
Width R318.7.1
CRC § 1205.2 Medium relevance — show source text
1205.2 Access and pathways. Roof access, pathways and spacing requirements shall be provided in accordance with Sections 1205.2.1 through 1205.3.3. Pathways shall be over areas capable of supporting firefighters accessing the roof. Pathways shall be located in areas with minimal obstructions, such as vent pipes, conduit or mechanical equipment.
Exceptions:
- Detached, nonhabitable Group U structures including, but not limited to, detached garages serving Group R-3 buildings, parking shade structures, carports, solar trellises and similar structures.
- Roof access, pathways and spacing requirements need not be provided where the fire code official has determined that rooftop operations will not be employed.
- Building-integrated photovoltaic (BIPV) systems where the BIPV systems are approved, integrated into the finished roof surface and are listed in accordance with UL 3741. The removal or cutting away of portions of the BIPV system during firefighting operations shall not expose a firefighter to electrical shock hazards.
1205.2.1 Solar photovoltaic (PV) systems for Group R-3 buildings. Solar photovoltaic (PV) systems for Group R-3 buildings shall comply with Sections 1205.2.1.1 through 1205.2.3.
Exceptions:
These requirements shall not apply to structures designed and constructed in accordance with the California Residen- tial Code .
These requirements shall not apply to roofs with slopes of 2 units vertical in 12 units horizontal (16.7-percent slope) or less.
1205.2.1.1 Pathways to ridge. Not fewer than two 36-inch-wide (914 mm) pathways on separate roof planes, from lowest roof edge to ridge, shall be provided on all buildings. Not fewer than one pathway shall be provided on the street or driveway side of the roof. For each roof plane with a photovoltaic array, not fewer than one 36-inch-wide (914 mm) pathway from lowest roof edge to ridge shall be provided on the same roof plane as the photovoltaic array, on an adjacent roof plane or straddling the same and adjacent roof planes.
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1205.2.1.2 Setbacks at ridge. For photovoltaic arrays occupying 33 percent or less of the plan view total roof area, a setback of not less than 18 inches (457 mm) wide is required on both sides of a horizontal ridge. For photovoltaic arrays occupying more than 33 percent of the plan view total roof area, a setback of not less than 36 inches (457 mm) wide is required on both sides of a horizontal ridge.
1205.2.1.3 Alternative setbacks at ridge. Where an automatic sprinkler system is installed within the dwelling in accordance with Section 903.3.1.3, setbacks at the ridge shall conform to one of the following:
- For photovoltaic arrays occupying 66 percent or less of the plan view total roof area, a setback of not less than 18 inches (457 mm) wide is required on both sides of a horizontal ridge.
- For photovoltaic arrays occupying more than 66 percent of the plan view total roof area, a setback of not less than 36 inches (914 mm) wide is required on both sides of a horizontal ridge.
CRC § 4.1 Medium relevance — show source text
SECTION R907—ROOFTOP-MOUNTED PHOTOVOLTAIC PANEL SYSTEMS
R907.1 Rooftop-mounted (PV) photovoltaic panel systems. Rooftop-mounted photovoltaic panel systems shall be designed and installed in accordance with Section R329 and the California Electrical Code .
R907.2 Fire classification. Rooftop-mounted photovoltaic panel systems shall have the fire classification as required by Section R902.4.
R907.3 Installation. Rooftop-mounted photovoltaic panel systems shall be installed in accordance with the manufacturer’s installation instructions.
R907.4 Photovoltaic panels and modules. Photovoltaic panel systems mounted on top of a roof shall be listed and labeled in accor- dance with UL 2703 and shall be installed in accordance with the manufacturer’s installation instructions.
R907.5 Fire safety provisions for photovoltaic panel system. Solar photovoltaic panel systems installed upon a roof or as an integral part of a roof assembly shall comply with the requirements of this code and the California Fire Code.
SECTION R908—REROOFING
R908.1 General. Materials and methods of application used for recovering or replacing an existing roof covering shall comply with the requirements of this chapter.
Exceptions:
- Reroofing shall not be required to meet the minimum design slope requirement of one-quarter unit vertical in 12 units horizontal (2-percent slope) in Section R905 for roofs that provide positive roof drainage.
- For roofs that provide positive drainage, recovering or replacing an existing roof covering shall not require the secondary (emergency overflow) drains or scuppers of Section R903.4.1 to be added to an existing roof.
R908.2 Structural and construction loads. The structural roof components shall be capable of supporting the roof covering system and the material and equipment loads that will be encountered during installation of the roof covering system.
R908.3 Roof replacement. Roof replacement shall include the removal of existing layers of roof coverings down to the roof deck.
Exceptions:
- Where the existing roof assembly includes an ice barrier membrane that is adhered to the roof deck and the existing sheathing is not water soaked or deteriorated to the point that it is not adequate as a base for additional roofing, the existing ice barrier membrane shall be permitted to remain in place and covered with an additional layer of ice barrier membrane in accordance with Section R905 where permitted by the roof covering manufacturer and new ice barrier underlayment manufacturer.
- Where the existing roof includes a self-adhered underlayment and the existing sheathing is not water soaked or deteriorated to the point that it is not adequate as a base for additional roofing, the existing self-adhered underlayment shall be
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permitted to remain in place and covered with an underlayment complying with Table R905.1.1(1), Table R905.1.1(2) and Table R905.1.1(3). 3.
CRC § 1511.10. Medium relevance — show source text
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A. SARA includes the area of the building’s roof space capable of structurally supporting a PV system, and the area of all roof space on covered parking areas, carports and all other newly constructed structures on the site that are compatible with supporting a PV system per Title 24, Part 2, Section 1511.10.
B. SARA does NOT include:
i. Any roof area that has less than 70 percent annual solar access. Annual solar access is determined by dividing the total annual solar insolation, accounting for shading obstructions, by the total annual solar insolation if the same areas were unshaded by obstructions. For steep slope roofs, only shading from existing permanent natural or manmade obstructions that are external to the dwelling, including but not limited to trees, hills, and adjacent structures, shall be considered for annual solar access calculations. For low slope roofs, all obstructions, including those that are external to the dwelling unit, and obstructions that are part of the building design and elevation features shall be considered for the annual solar access calculations. ii. Occupied roof areas as specified by CBC Section 503.1.4. iii. Roof area that is otherwise not available due to compliance with: a. Other state building code requirements, or b. Local building code requirements if local building code requirements are confirmed by the Executive Director .
EQUATION 150.1-C—ANNUAL PHOTOVOLTAIC ELECTRICAL OUTPUT kW PV = (CFA × A)/1000 +(N DU × B)
where:
kW PV = kW dc size of the PV system.
CFA = Conditioned floor area.
N DU = Number of dwelling units. A = CFA adjustment factor from Table 150.1-C. B = Dwelling unit adjustment factor from Table 150.1-C. Exception 1 to Section 150.1(c)14: For steep slope roofs, SARA shall not consider roof areas with a northerly azimuth that lies between 300 degrees and 90 degrees from true north. No PV system is required if the SARA is less than 80 contiguous square feet. Exception 2 to Section 150.1(c)14: No PV system is required when the minimum PV system size specified by Section 150.1(c)14 is less than 1.8 kW dc . Exception 3 to Section 150.1(c)14: Buildings with enforcement-authority-approved roof designs, where the enforcement authority determines it is not possible for the PV system, including panels, modules and components and supports and attachments to the roof structure, to meet the requirements of the American Society of Civil Engineers (ASCE), Standard 7-16, Chapter 7, Snow Loads. Exception 4 to Section 150.1(c)14: For buildings that are approved by the local planning department prior to January 1, 2020 with mandatory conditions for approval: a. Shading from roof designs and configurations for steep-sloped roofs, which are required by the mandatory conditions for approval, shall be considered for the annual solar access calculations; and b. Roof areas that are not allowed by the mandatory conditions for approval to have PVs shall not be considered in determining the SARA.
CRC § 170.2 Medium relevance — show source text
The PV capacity in kW dc shall not be less than the smaller of the minimum rated PV system capacity determined by Equation 170.2-D, or the total of all available solar access roof areas (SARA) multiplied by 18 for steep-sloped roofs or multiplied by 14 for low-sloped roofs. In mixed occupancy buildings, the minimum rated PV system capacity for the building shall be determined by applying Equation 170.2-D to the conditioned floor area of each of the listed building types and summing the capacities determined for each.
SARA include the area of the building’s roof space capable of structurally supporting a PV system, and the area of all roof space on covered parking areas, carports and all other newly constructed structures on the site that are compatible with supporting a PV system per Title 24, Part 2, Section 1511.10.
SARA does not include:
A. Any area that has less than 70 percent annual solar access. Annual solar access is determined by dividing the total annual solar insolation (accounting for shading obstructions) by the total annual solar insolation if the same areas were unshaded by those obstructions. For all roofs, all obstructions including those that are external to the building,
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and obstructions that are part of the building design and elevation features, may be considered for the annual solar access calculations.
B. Occupied roofs as specified by CBC Section 503.1.4. C. Roof area that is otherwise not available due to compliance with: i. Other state building code requirements, or ii. Local building code requirements if the local building code requirements are confirmed by the Executive Director.
EQUATION 170.2-D—PHOTOVOLTAIC DIRECT CURRENT CAPACITY
kW PVdc = (CFA × A)/1000
where:
kW PVdc = Minimum rated PV system capacity in kW.
CFA = Conditioned floor area in square feet.
A = PV capacity factor in W/square foot as specified in Table 170.2-U for the building type.
Exception 1 to Section 170.2(g): No PV system is required where the total of all available SARA is less than 3 percent of the conditioned floor area.
Exception 2 to Section 170.2(g): No PV system is required where the required PV system capacity is less than 4 kW dc .
Exception 3 to Section 170.2(g): No PV system is required if the SARA contains less than 80 contiguous square feet.
Exception 4 to Section 170.2(g): Buildings with enforcement-authority-approved roof designs, where the enforcement authority determines it is not possible for the PV system, including panels, modules, components, supports and attachments to the roof structure, to meet ASCE 7-16, Chapter 7, Snow Loads.
CRC § 5.1 Medium relevance — show source text
R329.5.1 BIPV roofing systems. BIPV roofing systems shall comply with Section R905.15. BIPV roof panels shall comply with Section R905.16.
R329.5.1.1 Fire classification. Building-integrated photovoltaic systems shall have a fire classification in accordance with Section R902.3.
R329.5.2 BIPV exterior wall coverings and fenestration. BIPV exterior wall coverings and fenestration shall comply with Section R705.
R329.6 Roof access and pathways. Roof access, pathways and setback requirements shall be provided in accordance with Sections R329.6.1 through R329.6.2.1. Access and minimum spacing shall be required to provide emergency access to the roof, to provide pathways to specific areas of the roof, provide for smoke ventilation opportunity areas, and to provide emergency egress from the roof.
Exceptions:
- Detached, nonhabitable structures, including but not limited to detached garages, parking shade structures, carports, solar trellises and similar structures, shall not be required to provide roof access.
- Roof access, pathways and setbacks need not be provided where the enforcing agency has determined that rooftop operations will not be employed.
- These requirements shall not apply to roofs with slopes of 2 units vertical in 12 units horizontal (17-percent slope) or less.
- BIPV systems listed in accordance with UL 3741, where the removal or cutting away of portions of the BIPV system during firefighting operations has been determined to not expose a firefighter to electrical shock hazards.
R329.6.1 Pathways. Not fewer than two pathways, on separate roof planes from lowest roof edge to ridge and not less than 36 inches (914 mm) wide, shall be provided on all buildings. Not fewer than one pathway shall be provided on the street or driveway side of the roof. For each roof plane with a photovoltaic array, a pathway not less than 36 inches wide (914 mm) shall be provided from the lowest roof edge to ridge on the same roof plane as the photovoltaic array, on an adjacent roof plane, or straddling the same and adjacent roof planes. Pathways shall be over areas capable of supporting firefighters accessing the roof. Pathways shall be located in areas with minimal obstructions such as vent pipes, conduit, or mechanical equipment.
R329.6.2 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 (457 mm) clear setback 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 36-inch (914 mm) clear setback is required on both sides of a horizontal ridge.
R329.6.2.1 Alternative setback at ridge. Where an automatic sprinkler system is installed within the dwelling or townhouse in accordance with NFPA 13D or Section R309, setbacks at ridges shall comply with one of the following:
- For photovoltaic arrays occupying not more than 66 percent of the plan view total roof area, not less than an 18-inch (457 mm) clear setback is required on both sides of a horizontal ridge.
- For photovoltaic arrays occupying more than 66 percent of the plan view total roof area, not less than a 36-inch (914 mm) clear setback is required on both sides of a horizontal ridge.
CRC § 150.1 Medium relevance — show source text
where:
kW PV = kW dc size of the PV system.
CFA = Conditioned floor area.
N DU = Number of dwelling units. A = CFA adjustment factor from Table 150.1-C. B = Dwelling unit adjustment factor from Table 150.1-C. Exception 1 to Section 150.1(c)14: For steep slope roofs, SARA shall not consider roof areas with a northerly azimuth that lies between 300 degrees and 90 degrees from true north. No PV system is required if the SARA is less than 80 contiguous square feet. Exception 2 to Section 150.1(c)14: No PV system is required when the minimum PV system size specified by Section 150.1(c)14 is less than 1.8 kW dc . Exception 3 to Section 150.1(c)14: Buildings with enforcement-authority-approved roof designs, where the enforcement authority determines it is not possible for the PV system, including panels, modules and components and supports and attachments to the roof structure, to meet the requirements of the American Society of Civil Engineers (ASCE), Standard 7-16, Chapter 7, Snow Loads. Exception 4 to Section 150.1(c)14: For buildings that are approved by the local planning department prior to January 1, 2020 with mandatory conditions for approval: a. Shading from roof designs and configurations for steep-sloped roofs, which are required by the mandatory conditions for approval, shall be considered for the annual solar access calculations; and b. Roof areas that are not allowed by the mandatory conditions for approval to have PVs shall not be considered in determining the SARA. Exception 5 to Section 150.1(c)14: PV system sizes determined using Equation 150.1-C may be reduced by 25 percent if installed in conjunction with a BESS. The BESS shall meet the qualification requirements specified in Joint Appendix JA12 and have a minimum cycling capacity of 7.5 kWh as defined in Joint Appendix JA12. 15. Ventilation system fault indicator display (FID): All HRV/ERV systems serving individual dwelling units shall have a fault indicator display (FID) that is ECC-Rater field verified as specified in Joint Appendix JA17.
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|TABLE 150.
CRC § 4.1.1 Medium relevance — show source text
R329.4.1.1 Roof load. Portions of roof structures not covered with photovoltaic panel systems shall be designed for dead loads and roof loads in accordance with Sections R301.4 and R301.6. Portions of roof structures covered with photovoltaic panel systems shall be designed for the following load cases:
- Dead load (including photovoltaic panel weight) plus snow load in accordance with Table R301.2.
- Dead load (excluding photovoltaic panel weight) plus roof live load or snow load, whichever is greater, in accordance with Section R301.6.
R329.4.1.2 Wind load. Rooftop-mounted photovoltaic panel or module systems and their supports shall be designed and installed to resist the component and cladding loads specified in Table R301.2.1(1), adjusted for height and exposure in accordance with Table R301.2.1(2).
R329.4.2 Fire classification. Rooftop-mounted photovoltaic panel systems shall have the same fire classification as the roof assembly required in Section R902.
R329.4.3 Roof penetrations. Roof penetrations shall be flashed and sealed in accordance with Chapter 9.
R329.5 Building-integrated photovoltaic systems. Building-integrated photovoltaic (BIPV) systems shall be designed and installed in accordance with Sections R329.5.1 through R329.5.2.
R329.5.1 BIPV roofing systems. BIPV roofing systems shall comply with Section R905.15. BIPV roof panels shall comply with Section R905.16.
R329.5.1.1 Fire classification. Building-integrated photovoltaic systems shall have a fire classification in accordance with Section R902.3.
R329.5.2 BIPV exterior wall coverings and fenestration. BIPV exterior wall coverings and fenestration shall comply with Section R705.
R329.6 Roof access and pathways. Roof access, pathways and setback requirements shall be provided in accordance with Sections R329.6.1 through R329.6.2.1. Access and minimum spacing shall be required to provide emergency access to the roof, to provide pathways to specific areas of the roof, provide for smoke ventilation opportunity areas, and to provide emergency egress from the roof.
Exceptions:
- Detached, nonhabitable structures, including but not limited to detached garages, parking shade structures, carports, solar trellises and similar structures, shall not be required to provide roof access.
- Roof access, pathways and setbacks need not be provided where the enforcing agency has determined that rooftop operations will not be employed.
- These requirements shall not apply to roofs with slopes of 2 units vertical in 12 units horizontal (17-percent slope) or less.
- BIPV systems listed in accordance with UL 3741, where the removal or cutting away of portions of the BIPV system during firefighting operations has been determined to not expose a firefighter to electrical shock hazards.
CRC § 2303.2.6.1 Medium relevance — show source text
2303.2.6.1
D5643/D5643M—2006(2018): Specification for Coal Tar Roof Cement, Asbestos-Free
Table 1507.10.2
D5664—2017: Test Methods for Evaluating the Effects of Fire-Retardant Treatments and Elevated Temperatures on Strength Properties of Fire-Retardant-Treated Lumber
2303.2.6.2
D5665/D5665M—99a(2021): Specification for Thermoplastic Fabrics Used in Cold-Applied Roofing and Waterproofing
Table 1507.10.2
D5726—98(2020): Specification for Thermoplastic Fabrics Used in Hot-Applied Roofing and Waterproofing
Table 1507.10.2
D5778—20: Standard Test Method for Electronic Friction Cone and Piezocone Penetration Testing of Soils
1813, 1813A.2
D5878—19: Standard Guides for Using Rock-Mass Classification Systems for Engineering Purposes
1803.5.1
D5882—16: Standard Test Method for Low Strain Impact Integrity Testing of Deep Foundations
1705.10
D6083/D6083M—21: Specification for Liquid Applied Acrylic Coating Used in Roofing Table 1507.10.2, Table 1507.13.3
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REFERENCED STANDARDS
D6162/D6162M—2016: Specification for Styrene Butadiene Styrene (SBS) Modified Bituminous Sheet Materials Using a Combination of Polyester and Glass Fiber Reinforcements
1507.11.2
D6163/D6163M—2016: Specification for Styrene Butadiene Styrene (SBS) Modified Bituminous Sheet Materials Using Glass Fiber Reinforcements
1507.11.2
D6164/D6164M—2016: Specification for Styrene Butadiene Styrene (SBS) Modified Bituminous Sheet Materials Using Polyester Reinforcements
1507.11.2
D6222/D6222M—2016: Specification for Atactic Polypropylene (APP) Modified Bituminous Sheet Materials Using Polyester Reinforcements
1507.11.2
D6223/D6223M—2016: Specification for Atactic Polypropylene (APP) Modified Bituminous Sheet Materials Using a Combination of Polyester and Glass Fiber Reinforcements
1507.11.2
D6298—2016: Specification for Fiberglass Reinforced Styrene-Butadiene-Styrene (SBS) Modified Bituminous Sheets with a Factory Applied Metal Surface
1507.11.2
D6305—21: Practice for Calculating Bending Strength Design Adjustment Factors for Fire-Retardant-Treated Plywood Roof Sheathing
2303.2.6.1
D6380/D6380M—2003(2018): Standard Specification for Asphalt Roll Roofing (Organic Felt) 1507.1.1, Table 1507.1.1(1), 1507.2.8.2, 1507.3.3, 1507.6.5
Frequently asked questions
Where exactly should the DC combiner box be placed relative to the array?
Place the combiner box where it produces the shortest practical conduit runs from the sub‑arrays while staying out of required 36‑inch pathways and close to a ridge/hip/valley or outside wall, per § R329.8.3.
Do DC conductors have to be in metallic conduit everywhere on the roof?
No — metallic conduit or raceways are specifically required when the DC wiring is located within enclosed spaces in a building; the code directs routing near ridges/hips/valleys but does not mandate metallic conduit across all exposed roof runs in § R329.8.3.
What pathway width must I keep clear for firefighter access on a residential roof?
Provide 36 in (914 mm) pathways from lowest roof edge to ridge as described in § R329.6.1.
Are there exceptions for very low‑slope roofs?
Yes — the roof access/pathway rules in R329.6 do not apply to roofs with slopes of 2 in 12 (≈16.7%) or less (CRC exception under R329.6).
I can’t keep conduit out of a pathway — what should I do?
You should first attempt to relocate the combiner box or reroute near the ridge/hip/valley to shorten runs per § R329.8.3. If not feasible, coordinate with the enforcing agency / fire code official because pathway obstruction and equipment placement can be subject to local approval.
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