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How to prepare for a solar inspection

The inspection is where the paper permit meets the real roof. An inspector's job is simple to state: confirm that what got installed matches what got approved, and that it's built to code. Prepare for that and you pass on the first visit; wing it and you get a re-inspection and another wait.

Rough vs final: two different visits

Many residential solar projects involve two inspections, checking different stages:

Not every project has a separate rough inspection; it depends on the install and your AHJ. Confirm which inspections apply to yours.

What the inspector verifies

Across both visits, the inspector is checking the same fundamentals that were approved on your permit set:

The single most important principle: the install must match the approved plans. If you changed something in the field, the change may need to be documented or re-approved.

The most common failure points

Re-inspections are usually caused by small, avoidable things:

FailureFix before the visit
Missing or wrong labelsInstall every label on the approved schedule
Install doesn't match plansDocument field changes; get re-approval if needed
Rapid shutdown not initiatingVerify the device and initiator function
Grounding gapsConfirm electrode, GEC, EGC, array bonding
Disconnect inaccessible/unlabeledEnsure access and correct marking

Labels alone account for a surprising share of failed finals — they're cheap to get right and easy to forget.

A pre-inspection checklist

Before the inspector arrives, have ready:

Physical access is underrated — an inspector who can't reach a disconnect or safely get to the array may not be able to complete the inspection at all.

Match plans to reality: before you install, run your design through the free Design Grader — it verifies the NEC items an inspector checks, so your approved plans and your finished work line up.

After you pass

A passed final inspection clears the AHJ side, but you're not done: the sign-off has to reach your utility so it can grant permission to operate (PTO) — the final authorization to energize. Make sure the inspection result gets to the utility promptly so your PTO isn't held up by paperwork.

Requirements vary by jurisdiction, so confirm which inspections apply and what your AHJ expects, and keep a licensed electrician involved through inspection and commissioning. Match the install to the approved plans, get the labels right, and provide clean access — that's what turns an inspection into a formality instead of a setback.

FAQ

What does a solar inspector check?

The inspector verifies the installed system matches the approved plans — wiring, overcurrent protection, grounding, rapid shutdown, labels, and mounting — and that the work is done to code. A final inspection is required before the utility grants permission to operate.

What is the difference between a rough and a final inspection?

A rough inspection checks work that will be covered up, such as mounting and rough wiring, before it's concealed. The final inspection checks the completed, energizable system, including labels and disconnects.

What causes a solar inspection to fail?

Common failures are missing or wrong labels, work that doesn't match the approved plans, missing rapid-shutdown initiation, grounding gaps, and inaccessible or unlabeled disconnects.

Related: Permits & inspections

Educational reference, reviewed 2026-07. A design aid, not a substitute for a licensed electrician or PE. Confirm the enforced NEC edition and local amendments with your AHJ.

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