Guides
Solar Installer Change Order Process to Avoid Losing Money
Solar installer change order process mistakes can hide for months and drain margins. See US-tested failure cases, consequences, and prevention steps.
What to take away
- Unpaid change work is a written-contract failure, not a customer problem.
- Verbal approvals often survive until the invoice arrives, then disappear.
- The worst change order losses hide for one or two solar seasons before surfacing.
- Prevention is a one-page signed form before the crew moves.
The costly one
A homeowner asks the crew to add one more panel or move a conduit run. The lead installer says yes and does the work. No signed form, no revised price.
After the final invoice, the homeowner disputes the extra charge. The contractor eats the labor and materials or files a lien and burns a referral. A change order is a written amendment to the original construction contract. It is separate from the solar installer quotes that started the job.
Prevention: get a signed change order with a clear price, scope, and schedule delta before the crew moves.
Example: A Denver array move without a signed form
Imagine a Denver crew moves four modules from a west roof face to an east face after a homeowner texted "yes." The crew does not write a change order. The production loss from east orientation does not show until winter. The homeowner refuses to pay the four-figure adder. A signed form showing the shading impact would have stopped the work or set expectations.
The ones that look fine at first
A crew changes rail spacing or inverter location because the original spot is blocked. It seems minor, so no one writes it. Later an inspection fails because the new location violates NFPA 70 clearance rules. The repair costs more than a change order would have.
Another common one: substitute a cheaper panel model due to supply delays without a written change order. It looks identical on the roof. Months later a panel fails, and the manufacturer denies the warranty because the substituted model was not on the approved list. Use the solar installer warranty terms checklist to compare terms before signing.
Prevention: any field change that alters code-relevant installation or equipment must go through a change order and a technical review.
The ones that only show up later
An installer changes the inverter size or battery capacity after a supply issue. The system works fine for one season. Then a hot summer or cold snap exposes an undersized capacity. The owner claims misrepresentation, and the contractor has no signed scope change to show. This failure is invisible for a season or more.
Another hidden one: the crew reroutes conduit underground without documenting depth. Two winters later, frost heave damages the shallow conduit. The contractor is blamed for a defect that was not in the original contract. Prevention: record every equipment substitution and physical route change, with performance impact and an as-built sketch, on a signed change order.
What they have in common
Each failure starts as a verbal instruction treated as authorization. The crew makes a field decision because it seems faster. A construction contract requires a signed amendment to keep the original scope and price enforceable. On commercial jobs, OSHA and prevailing wage rules can change labor costs enough to require a change order. State prompt payment laws may set deadlines for approving or rejecting a change order, and missing those deadlines can waive rights.
| Change order failure | Hidden period | Consequence | Prevention |
|---|---|---|---|
| Verbal approval for extra panel | Until final invoice | Unpaid labor and materials | Signed form before work |
| Panel model substitution | Months to years | Warranty denial | List new model and warranty terms |
| Inverter size change | One season or more | Capacity shortfall complaint | Document performance impact |
| Shallow conduit reroute | Two winters | Frost damage claim | Record depth and as-built sketch |
- Get a signed change order before any field modification.
- Include a revised price or a clear zero-cost note.
- List equipment substitutions with warranty and performance impact.
- Capture a site photo or as-built sketch for physical changes.
- Send the signed change order to the homeowner within one business day.
Some owners treat change order forms as a rejection of the original quote. That framing is backwards. A clear change order keeps the original price and scope intact while isolating the new work. It also creates a paper trail for warranty claims and tax credit eligibility.
When a change order affects the federal tax credit, update the tax credit paperwork in the same approval.
Common questions
Does a text message count as a signed change order? In many states, no. A written change order with a signature or an electronic signature that complies with state law is the safer record.
How much can I charge for a change order fee? A flat fee of $150 to $500 is common for administrative time, but the real cost recovery is in the revised scope and price. Check your state prompt payment law for timing.
What if the homeowner refuses to sign a change order? Stop work on the changed scope and document the refusal. The original contract may allow you to proceed only with written approval.
Can a change order protect me from a seasonal performance complaint? Yes, if it lists the specific equipment change and its expected production or capacity impact. The written record shifts the dispute from memory to contract terms.
