How to inspect a solar PV installation

Step by step

1. 1

   Verify roof attachment and flashing at every penetration

   Confirm each mount, stanchion, or ballast bears as the design shows and that every roof penetration is flashed and sealed into the roofing system with the manufacturer's flashing, not just sealant. On a warranted roof, verify the roofer or an approved installer made the penetrations so the warranty holds.

2. 2

   Confirm structural loading and racking

   Verify the racking is the specified system, attached and spaced per the approved layout, and that the structural review of the added dead, live, and uplift load is complete where required. Frame this as observed against the approved design; the engineer of record governs the structural adequacy.

3. 3

   Check module mounting and grounding

   Confirm modules are the specified product, clamped at the manufacturer's points and torque, undamaged, and bonded and grounded through the listed method. Improper clamping or a broken bond path is both a performance and a safety defect.

4. 4

   Verify DC wiring, conductor management, and connectors

   Observe that DC wiring is supported off the roof, protected from abrasion and UV, that connectors are the matched, listed type fully seated, and that conductors aren't left to chafe on racking or membrane. Mismatched or loose DC connectors are a documented fire risk — flag them for the licensed electrician.

5. 5

   Confirm rapid shutdown, labeling, and disconnects

   Verify the rapid-shutdown provisions, placards, disconnects, and required labeling are installed per the design and are legible and accessible. These are life-safety features for firefighters — confirm they're present and observe function; the electrician and AHJ certify the system.

6. 6

   Check inverters, AC tie-in, and interfaces

   Confirm inverters are the specified units, mounted with the required clearances and ventilation, and that the AC tie-in, metering, and any monitoring interface are complete and coordinated. Verify the point of interconnection matches the approved plan and utility requirements.

7. 7

   Observe commissioning and the AHJ inspection

   Confirm the licensed electrical contractor commissions the array and the AHJ and, where applicable, the utility inspect and authorize the system before it's energized to grid. Record what you observe; certification and permission to operate are the electrician's, AHJ's, and utility's call.

8. 8

   Document the roof and electrical work and close out

   Photograph flashings and attachments before anything covers them, keep the electrical inspection and commissioning records in the file, and track roof-penetration or safety deficiencies to closure so neither the roof warranty nor the energization is held up.

Questions people ask

Why is the roofing part of a PV inspection so important?

Because every mount is a penetration through a roof that has to stay watertight for decades, often under warranty. If the attachments aren't flashed into the roofing system by an approved installer, you've traded a solar array for a leaking roof and a voided warranty.

Who certifies and energizes the PV system?

The licensed electrical contractor makes up and commissions the electrical work, the AHJ inspects and approves it, and the utility authorizes interconnection where it applies. Your role is to verify the building and roofing scope and to observe and document the electrical work — not to energize or certify it.