Solar Installer Warranty Terms Checklist for New Contracts

What to take away

• Panel product warranties in the US commonly run 25 years, while string and hybrid inverters often carry 10 to 12 years. Those are the manufacturer terms, not the installer's.
• The installer's own workmanship warranty is the term most buyers never read. Ask for its length in writing, and ask who pays labor when a part fails in year 12.
• Ask the questions below verbatim. Vague answers to any of them are a reason to slow down, not a reason to sign.
• Three answers should end the conversation: no written workmanship term, no named manufacturer, and no answer on who files the claim.
• Every promise belongs in the contract. A brochure is not a warranty document.

Panel and inverter warranties are separate products

A solar panel warranty comparison usually starts with the module datasheet. Most tier-one manufacturers offer a 25-year product warranty against defects and a separate 25-year performance warranty guaranteeing a stated percentage of original output. Those two numbers are different promises, and the second one is the one that matters in year 20.

Inverters are the shorter-lived component. Ten years is a common US term, with extensions sold separately. Ask whether the extension is priced into the quote or offered later at a markup. The DOE homeowner guide on going solar explains how equipment and financing terms get bundled, which is why the inverter line is easy to bury.

Workmanship is a third warranty, and it belongs to the contractor. It covers the roof penetrations, the racking torque, the conduit runs and the flashing. A 25-year panel warranty does nothing if water enters through a poorly sealed mount in year three.

Questions to ask before signing

Ask these as written and write down the answers.

1. "What is the length of your workmanship warranty, in years, and what does it exclude?"
2. "If a panel fails in year 12, who files the manufacturer claim, and who pays the labor to remove and reinstall it?"
3. "Which manufacturer and model number will be installed, and can I see the warranty document before I sign?"
4. "What is your state contractor license number, and is it current?"
5. "If you subcontract the roof work, does your warranty still cover that crew's work?"

Question two is the one that separates a competent supplier from a confident one. Labor is often excluded from manufacturer coverage. Removal and reinstallation on a pitched roof can run into four figures, so the answer decides whether the warranty has real value.

Evidence to request

Ask for documents, not assurances.

• The state contractor license number, which you can verify on the state licensing board website.
• The manufacturer warranty PDFs for the exact model numbers quoted.
• A certificate of insurance naming general liability limits.
• The signed contract with the workmanship term written into the body.
• The names of the installation crew, or the subcontractor's license number.

Licensing varies by state: some license solar work under a general electrical contractor license, while others use a dedicated classification. NABCEP certification is a voluntary credential, not a license, and it does not replace state registration.

NABCEP certification and what it changes for American solar hiring and insurance explains where the credential fits and where it does not.

A warranty is only as good as the company that has to honor it. Check how long the installer has operated under the current business name, and whether that entity will still exist in year 15.

Answers that should end the conversation

Three replies are disqualifying on their own.

"Our warranty matches the manufacturer's." This means there is no workmanship term. The installer is passing the panel maker's promise off as their own, and roof leaks will not be covered.

"We handle claims, you do not need to worry about it." Refusing to name the process, the timeline or the responsible party is a sign the claim path is not documented. Ask for it in the contract instead.

"The crew is whoever is available that week." Unnamed subcontractors break the warranty chain. If the installer cannot say who is on the roof, no one owns the workmanship term. Subcontractor liability concepts are worth reading before you accept this answer, and the subcontractor overview covers how responsibility shifts in construction contracts.

A fourth soft signal: any answer that quotes a warranty length but cannot produce the document.

What the contract must say

Know the workmanship term in years, exclusions, and manufacturer model numbers for panels, inverters, and racking. Understand the claim process, including who files and who pays labor.

Review transfer terms if you sell the house, because many US workmanship warranties transfer only once or not at all. Review the change order process, since a scope change can void coverage.

Our sample solar installer quotes and the template behind them shows how these terms normally sit beside pricing lines.

State consumer protection law matters here. Many states give homeowners a right to cancel within three business days on a home solicitation sale, and some require written warranty disclosures. The general warranty law overview covers how express and implied warranties interact, which helps when a contract tries to disclaim everything except the manufacturer terms.

If your project sits in a hurricane or hail zone, the equipment warranty is a different conversation. Our piece on Miami hurricane codes and salt air covers what coastal conditions do to coverage.

Common questions

Does a 25-year panel warranty cover labor? Usually not. Most manufacturer product warranties cover the replacement module only. Labor, shipping and roof access are commonly excluded, which is why the installer's workmanship term matters.

How long should a workmanship warranty be? Terms in the US commonly run from 5 to 10 years, with some installers offering longer. Anything under 5 years is thin for roof penetrations that take years to leak.

Can I lose warranty coverage by adding a battery later? Possibly. Adding equipment can change the system design and the inverter load. Ask the installer in writing whether a future battery addition affects coverage, and check the change order process before approving any modification.

What if the installer goes out of business? Manufacturer warranties usually survive because they attach to the equipment, but workmanship coverage does not. Ask whether the manufacturer backs a labor allowance, and keep the original contract and serial numbers.

A final check: read the warranty before the crew arrives, not after. Fixing terms after installation is far harder than negotiating them before the deposit.