Pacific Northwest Single-Family: 9 Issues Found

Summary: The arc flash and shock hazard warning label on drawing PV-7 indicates '480 VAC SHOCK HAZARD WHEN COVER IS REMOVED' with approach boundaries calculated for 480V (e.g., '42 INCH LIMITED APPROACH,' '12 INCH RESTRICTED APPROACH - 500 V CLASS 00 GLOVES'). However, the AC disconnect data label on the same sheet explicitly states 'NOMINAL OPERATING...

Why it matters: IBC Section 2701.1 requires that NFPA 70 shall govern the design, construction, erection and installation of electrical components and systems. The drawing itself cites NEC 110.16 as the basis for the arc flash label. An arc flash label with an incorrect voltage of 480V instead of the actual 240V results in inaccurate flash hazard boundaries,...

Suggested next step: Request the electrical engineer verify and correct the arc flash/shock hazard warning label to reflect the actual 240V AC system voltage, including recalculated flash hazard boundary, incident energy, and all approach distances (limited, restricted, and prohibited) appropriate for 240V rather than 480V.

RFI draft: Request the electrical engineer verify and correct the arc flash/shock hazard warning label to reflect the actual 240V AC system voltage, including recalculated flash hazard boundary, incident energy, and all approach distances (limited, restricted, and prohibited) appropriate for 240V rather...

Summary: The arc flash and shock hazard warning label on the drawing states '480 VAC SHOCK HAZARD WHEN COVER IS REMOVED' with approach boundaries and PPE requirements calculated for 480V (42 inch limited approach, 12 inch restricted approach with 500 V Class 00 gloves, 1 inch prohibited approach with 500 V Class 00 gloves). However, the system's actual...

Why it matters: This incorrect voltage on the arc flash label will result in the wrong shock hazard boundaries and PPE specifications being posted at the equipment. An electrical inspector is highly likely to flag the 480V label on a 240V residential PV system, requiring label replacement and causing an inspection delay. Additionally, the incorrect voltage and...

Suggested next step: Request the designer to revise the arc flash warning label to reflect the actual system operating voltage of 240V and to recalculate all approach boundaries (limited, restricted, and prohibited) and PPE requirements based on the correct 240 VAC rating.

RFI draft: Request the designer to revise the arc flash warning label to reflect the actual system operating voltage of 240V and to recalculate all approach boundaries (limited, restricted, and prohibited) and PPE requirements based on the correct 240 VAC rating.

Summary: The RockIt Smart Slide product specification page, included in the construction documents as a rooftop PV mounting component, explicitly lists its testing and certifications under a 'Testing & Documentation' heading: UL441 Rain Report, TAS 100(A)-95 Wind and Wind Driven Rain Resistance, Mechanical Load Test/Structural Capacity Certification,...

Why it matters: Without demonstrated UL 2703 fire classification for the PV mounting system, the rooftop solar installation may fail to meet the fire resistance requirements mandated by the IRC. This could result in plan review rejection by the building department, requiring either proof of UL 2703 listing for the specified product or substitution with a...

Suggested next step: Request the manufacturer's UL 2703 listing documentation for the RockIt Smart Slide mounting system. If UL 2703 fire classification cannot be provided for this product, confirm whether the complete PV system assembly (including the Smart Slide) has been tested and listed per UL 2703 as required by IRC Section R902.4. If no UL 2703 certification...

RFI draft: Request the manufacturer's UL 2703 listing documentation for the RockIt Smart Slide mounting system. If UL 2703 fire classification cannot be provided for this product, confirm whether the complete PV system assembly (including the Smart Slide) has been tested and listed per UL 2703 as required...

Summary: The `ATTACHMENT DETAIL` identifies `ROCKIT MOUNT`, `PV MODULE`, `ROOF MEMBRANE`, and `2 x #12 WOOD SCREW WITH 2' MIN. EMBEDMENT AND FLAT WASHER`, and its graphic shows the mount base sitting at the roof membrane with vertical fasteners extending downward. The `SOLAR PV ARRAY SECTION VIEW` likewise shows the mount fastened at the `ROOF SURFACE`...

Why it matters: If this detail is built as shown, the roof weather barrier at the PV attachment penetrations is not code-compliant and can result in permit comments, failed inspection, water intrusion, and costly roof/PV rework after installation.

Suggested next step: Revise the PV attachment detail to identify and depict the flashing or flashed attachment assembly used at each roof penetration for the `ROCKIT MOUNT`, and confirm compliance with IRC Section R903.2.

RFI draft: Revise the PV attachment detail to identify and depict the flashing or flashed attachment assembly used at each roof penetration for the `ROCKIT MOUNT`, and confirm compliance with IRC Section R903.2.

Summary: The mounting details on PV-3 (page 5) consistently specify the roof attachment fastener as a '#12 WOOD SCREW' paired with a 'FLAT WASHER' in both the Solar PV Array Section View and the Attachment Detail. However, the manufacturer's product cut sheet on page 18 for the same fastener (RI SMART SCREW #12X3' W/BW, part number 2011025) describes it...

Why it matters: A flat washer provides only load distribution, whereas a sealing washer assembly with EPDM rubber provides both load distribution and a watertight seal at the roof penetration. If the installer follows the PV-3 drawing literally and uses a flat washer instead of the manufacturer's sealing washer, the roof penetrations would lack proper water...

Suggested next step: Request clarification on the correct fastener specification for the RockIt Smart Slide roof attachment. Specifically: (1) Should the screw be a wood screw or a self-tapping screw? (2) Should the washer be a flat washer or a sealing washer assembly with EPDM rubber as shown on the manufacturer's cut sheet? Please update PV-3 mounting details or...

RFI draft: Request clarification on the correct fastener specification for the RockIt Smart Slide roof attachment. Specifically: (1) Should the screw be a wood screw or a self-tapping screw? (2) Should the washer be a flat washer or a sealing washer assembly with EPDM rubber as shown on the manufacturer's...

Summary: The arc flash and shock hazard placard shown on PV-7 (Labels) states '480 VAC SHOCK HAZARD WHEN COVER IS REMOVED.' However, the three-line diagram on PV-4 clearly identifies the main service panel as '1PH, 120/240V 60HZ,' and the AC disconnect equipment label on the same PV-7 sheet specifies 'NOMINAL OPERATING AC VOLTAGE: 240V.' The 480 VAC...

Why it matters: Installing an arc flash label with an incorrect voltage rating of 480 VAC on a 120/240V residential system is a safety hazard. It misrepresents the shock hazard level, could lead to incorrect PPE selection, and will likely be flagged by the AHJ during inspection. The approach distances listed on the placard may also be incorrect if they were...

Suggested next step: Please confirm the correct voltage for the arc flash and shock hazard placard. The system three-line diagram shows 120/240V and the AC disconnect label shows 240V, but the arc flash placard specifies 480 VAC. Please revise the arc flash placard to reflect the actual system voltage and recalculate the flash hazard boundary, approach distances,...

RFI draft: Please confirm the correct voltage for the arc flash and shock hazard placard. The system three-line diagram shows 120/240V and the AC disconnect label shows 240V, but the arc flash placard specifies 480 VAC. Please revise the arc flash placard to reflect the actual system voltage and...

Summary: The construction note states 'THE MAIN SERVICE PANEL WILL BE EQUIPPED WITH A GROUND ROD OR UFER.' That makes a single ground rod one of the permitted grounding options on the sheet. IRC Section E3608.4 requires a single rod electrode to be supplemented by an additional electrode unless the rod qualifies for the exception, and IRC Section...

Why it matters: If the installation follows this note with only one rod, the service grounding electrode system can fail inspection and require added electrodes or field testing after installation.

Suggested next step: Revise the grounding note to identify the complete grounding electrode system at the main service. If a rod electrode is used, show the required supplemental electrode or specify documented resistance-to-earth testing of 25 ohms or less, and clarify that all electrodes present are to be bonded together.

RFI draft: Revise the grounding note to identify the complete grounding electrode system at the main service. If a rod electrode is used, show the required supplemental electrode or specify documented resistance-to-earth testing of 25 ohms or less, and clarify that all electrodes present are to be bonded...

Summary: The signage notes on PV-7 (Labels) specify 'C. ARIAL FONT' for all marking, while the notes on PV-7A (Site Placard) specify 'C. AERIAL FONT.' 'Arial' is a recognized typeface; 'Aerial' is not a standard font name. These two sheets provide conflicting font requirements for the safety signage.

Why it matters: This discrepancy could cause confusion during signage fabrication. If 'AERIAL' on PV-7A is a typographical error for 'ARIAL,' it should be corrected to maintain consistency. If a different font is intentionally specified for the site placard, the design intent should be clarified. The AHJ may question inconsistent signage specifications during...

Suggested next step: Please clarify the required font for safety signage. PV-7 Note 2C specifies 'ARIAL FONT' while PV-7A Note 2C specifies 'AERIAL FONT.' Please confirm whether 'AERIAL' is a typo for 'ARIAL' and revise accordingly to ensure consistency across the drawing set.

RFI draft: Please clarify the required font for safety signage. PV-7 Note 2C specifies 'ARIAL FONT' while PV-7A Note 2C specifies 'AERIAL FONT.' Please confirm whether 'AERIAL' is a typo for 'ARIAL' and revise accordingly to ensure consistency across the drawing set.

Summary: The three-line diagram on PV-4 labels the equipment as '(N) ENPHASE COMBINER BOX,' while the site placard on PV-7A identifies the same equipment as 'ENPHASE COMBINER PANEL.' These are two different terms for the same piece of equipment in the PV system, creating an inconsistency in the drawing set.

Why it matters: Inconsistent naming of the same equipment between the electrical diagram and the site placard could cause confusion during installation and inspection. The site placard is a safety document intended for first responders and maintenance personnel; its equipment labels must match the actual installed equipment nomenclature shown on the electrical...

Suggested next step: Please clarify the correct designation for the Enphase combiner equipment. PV-4 calls it 'ENPHASE COMBINER BOX' while PV-7A calls it 'ENPHASE COMBINER PANEL.' Please revise to use a consistent name across all sheets.

RFI draft: Please clarify the correct designation for the Enphase combiner equipment. PV-4 calls it 'ENPHASE COMBINER BOX' while PV-7A calls it 'ENPHASE COMBINER PANEL.' Please revise to use a consistent name across all sheets.