Solar panel warranties explained: product, workmanship, roof

A solar panel warranty is really several separate promises from different companies. The panel maker backs the product and its output over time. The installer backs the installation work. A roofer or roofing manufacturer backs the roof. Each has its own term, exclusions and claim steps, and only the signed documents decide what is covered.^1,2,3

What follows is a general explanation of how warranties work, drawn from Maryland and federal public documents. It isn’t about any one company’s terms. The two main references date from 2018, so every number below carries its year, and the one 2026 figure is labeled as a program rule.

Who owes you what under a solar warranty?

A rooftop system carries several layers of coverage, and the roof adds its own. Because different companies issue them, a claim goes to whichever company made the part or did the work. Sort your paperwork by issuer before something breaks, not after.^2,4

How long do the terms run?

Public guides give ranges, not one answer. Two 2018 documents describe typical terms: the Maryland Energy Administration (MEA) consumer guide and a report from the National Laboratory of the Rockies (NLR, formerly the National Renewable Energy Laboratory). The third column is different: minimums Maryland’s solar access program requires of its contractors in 2026.^1,4,8

Read the third column as a rulebook for one program, not as a survey of what the market sells or a trend line. Participating contractors must provide at least a 25-year manufacturer material warranty on modules, 10 years on inverters and 10 years of workmanship coverage, and the warranty terms must name the responsible party for each warranty.⁸ Outside the program, the 2018 columns show what public guides called typical, and your own paperwork controls.

If you’re buying through the Maryland Solar Access Program, MEA’s consumer protection policy sets these minimums for the program. Ask any installer whether it is on the program’s contractor list. Outside the program, the numbers in your own contract and warranty documents are the terms you can point to.

What’s the difference between a product warranty and an output warranty?

A product warranty covers defects in materials and manufacturing. An output warranty promises a minimum power level that falls on a schedule. Proving an output claim takes an inspection by a qualified professional, and the remedy might be repair, replacement, extra panels or cash. The remedy clause is where the money is.^1,5,4

Normal aging is already built into the schedule. MEA’s 2018 guide says industry standards assume an output drop of 0.5 percent per year.¹⁰ Most warranties protect against a larger decline, so ordinary aging, by itself, isn’t a claim.

The 2018 NLR report lists reasons lenders distrust manufacturer warranties. It’s written with large systems in mind, but four of its points would hit a homeowner just as hard:

• A manufacturer’s warranty might pay for a replacement panel but not the labor to remove, ship and reinstall it. A dealer’s promise to cover that labor “rarely makes it into the final contract.”⁵
• Showing that a module underperforms is difficult, and might need an expensive standardized test of each module.⁵
• The warranty often lets the manufacturer “repair, replace, or supplement.” Extra panels may not fit the rack or the electrical design, and adding capacity can trigger a new interconnection agreement and permitting.⁵
• A manufacturer can pay the cash value of the lost capacity, which may be less than the original price as panel prices fall.⁵

MEA adds that a claim for lost output normally needs a qualified professional to check electrical output and thermal images for hot spots.⁴

The trap in a “25-year warranty” is hearing it as a free panel swap. An output warranty promises a power level. Whether anyone pays the crew to climb up and replace a panel is a separate line in the document.⁵

What does an installer’s workmanship warranty cover?

A workmanship warranty is the installer’s promise about its own work. MEA says warranties should cover equipment and workmanship, plus any roof damage during installation, where that applies. The installation warranty may also require the original installer to maintain the system, so read that condition before anyone else touches the equipment.^2,6

The documents don’t agree on one standard term. MEA’s 2018 guide called at least five years generally accepted, and the 2018 NLR report said an installer warranty may be only one to five years.^2,9 The Maryland program’s 2026 policy requires 10 years from its contractors.⁸ Whatever the number, get the exact term and the start date in writing.

Four more points shape this layer:

• Subcontractors. MEA says the contract should identify who does each part of the job and who answers for warranties on work done by subcontractors.⁶
• Racking. MEA says that if the installation is done incorrectly, fixing it should be the installer’s responsibility, not the racking manufacturer’s.⁴
• Claims. MEA says your installer should handle equipment warranty claims.⁶
• The contract. Maryland’s home improvement law (section 8-501) says each home improvement contract shall be in writing and legible, and signed by each party. The contents it lists include a description of the work and the materials, and the agreed price. Warranty terms aren’t among the listed items, so put the warranty in the contract or attach the documents it names.¹¹

Does a roof warranty still apply with panels on top?

That comes down to the roof warranty’s own text. The 2018 NLR report says roofs under warranty need annual preventive maintenance, and that an “overburden waiver,” often required to keep a roof warranty, means agreeing to remove the array whenever the roofer needs access. Get written confirmation from the roof warranty’s issuer before panels go on.³

One caution about that report: its roof chapter prices repairs on a scale “typical of commercial-scale rooftop PV.” The cost figures don’t transfer to a house, so none are used here. The logic does transfer, and two current documents back it up. The Maryland program’s FY27 policy requires contractors to disclose roof inspections, repairs and warranties, and to disclose the condition of the roof and the chance the array will need to come off for roof work. The Federal Trade Commission (FTC) lists “what happens if you need to repair your roof after the system is installed” among the points to compare when you weigh bids for a lease or a power purchase agreement (PPA).^12,7

Leave roof access to professionals. Our guide on replacing your roof before going solar covers the sequencing question.

What happens if the installer or manufacturer closes?

Each warranty is only as good as the company behind it. When a manufacturer closes, its coverage may end. When an installer closes, nobody is left to perform its workmanship promise. In Maryland, the Home Improvement Guaranty Fund may reimburse some losses from a licensed contractor’s poor or abandoned work, but it’s a limited remedy and separate from any warranty.^2,13

As of October 2026, the Maryland Home Improvement Commission (MHIC) says solar panel systems must be mounted by a licensed home improvement contractor.¹⁵ Maryland law defines the “actual loss” the Guaranty Fund covers as the costs of restoration, repair, replacement or completion that arise from an unworkmanlike, inadequate or incomplete home improvement, and MHIC’s FAQ adds abandoned jobs.^16,13 The limits that matter most:

• An award can’t exceed $30,000 per claimant, or the amount the owner paid the contractor, whichever is less, according to MHIC.¹³
• MHIC says the most the Fund will pay for one contractor is $250,000 across all claimants.¹³ If approved claims exceed that, MHIC says it prorates them, which matters when a closed installer left many customers behind.¹³
• An owner can claim only if the owner lives in the home or owns no more than three residences.¹³
• MHIC says a claim must be brought within three years after the owner discovered, or should have discovered, the loss.¹³
• MHIC’s FAQ says the Home Improvement Law requires a homeowner to comply with a written agreement to arbitrate before recovering from the Fund, and describes it as a good-faith effort to arbitrate first.¹³
• MHIC says the Fund doesn’t cover attorney fees or court costs, and won’t reimburse money paid to an unlicensed contractor to fix the work.¹³
• MHIC reports a large backlog of claims waiting for hearings, even where the contractor is out of business.¹³

The Fund addresses poor or incomplete installation work. It doesn’t replace a manufacturer’s output warranty. It’s a Maryland remedy for work by Maryland-licensed contractors, so owners in the District of Columbia or Virginia should ask their own consumer or licensing office what recovery options exist. The limits come from statute and can change, so confirm them with MHIC before relying on them. Our guide on what to do when a solar installer goes out of business goes further.

Here’s a hypothetical example, not a real property. A leak appears near a roof mount, a separate roofer did the roof, and the installer’s contract names a workmanship warranty from a company that has since closed. Work through three questions in order. Who issued the roof warranty, and does it need written notice before anyone works on the mount? Who issued the workmanship warranty, and is that company still operating? If not, was the contractor licensed by MHIC, and is the loss within three years of when you found it?¹³ It shows an order of questions, not who is responsible.

What happens to the warranties when you sell the house?

Warranties don’t follow the house automatically. MEA says to complete any change-of-ownership forms so the warranty transfers to the new owners. The NLR report adds that a manufacturer may refuse a warranty once the original purchaser no longer owns the equipment, though many offer a transfer process.^2,17

That process is described as paperwork, a small fee and a finalization period, usually 30 days after the sale. Start it alongside the closing, not after it.¹⁷ Buyers should ask the seller for the existing warranties and check that the paperwork is in order. If a third party owns the system, the buyer may have to take over the contract.¹⁴ Our guide on buying a house with solar panels walks through the buyer’s side.

What should you get in writing before you sign?

Collect every warranty document, the exact name of each issuer, each term and start date, the exclusions and the claim steps. Then settle who removes and reinstalls panels for repairs, who covers roof damage, whether the warranty transfers and what happens if a company closes. Put the answers in the contract or attach the documents it names.^6,7

Use this list when you compare bids:

1. Collect the documents. Your contractor should hand you copies of the warranties. Get the panel, inverter, mounting and installation documents separately.⁶
2. Name every issuer. Match each layer to a company, and mark which are manufacturers and which is the installer.⁴
3. Check the labor. Find out who pays to remove, ship and reinstall a panel under a claim, and get that in the contract, not in a proposal.⁵
4. Read the remedy. Does the output warranty pay in repair, replacement, extra panels or cash?⁵
5. Settle the roof. Get roof-damage coverage during installation in writing, and have the roof warranty’s issuer confirm the mounting plan.^6,3
6. Find the upkeep conditions. What maintenance, or which service provider, keeps each warranty valid?^9,2
7. Pin down any output promise. If the seller states a minimum energy amount, how is it measured and how does the company pay if the system falls short?^7,9
8. Plan for transfer and closure. Get the ownership-change forms, and a named party behind each layer if a company closes.^17,2
9. Check the license. MHIC licenses home improvement contractors, and the Fund applies only to licensed contractors’ work.^13,15 Our guide on checking a solar contractor’s license in Maryland shows how.

When the general rules bend

The sections above mostly assume you own the system outright. Five situations change the picture, so read your own contract first.

• Leased or PPA systems. The FTC’s consumer page (April 2022) says a lease or PPA customer doesn’t own the system. Check who maintains and repairs it, what minimum energy the contract promises, which warranties and repairs it includes, and what happens if the roof needs work.⁷
• Batteries. The NLR report says running batteries outside the manufacturer’s temperature range can shorten battery life and possibly void product warranties. The battery’s own document controls.⁹
• Commercial roofs. NLR notes that some roofing manufacturers offer 25-year warranties, but those typically apply to commercial projects and require certain installation procedures.³
• Insurance. MEA says homeowner’s insurance often covers storm damage that a manufacturer’s warranty doesn’t, and that you normally must tell your insurer about the system first.⁶
• Unlicensed work. MHIC says the Guaranty Fund won’t reimburse money paid to an unlicensed contractor to correct work.¹³

How do you start if you already own a system?

If you already own a system, start by gathering the contract, warranty documents, equipment makes and models, and monitoring history. Then get each company to put its terms in writing. Soleil Energy’s monitoring and maintenance page says it services systems it didn’t install, so you can ask about an existing system even if you didn’t buy from the company.¹⁸

To talk through an existing system, request a system assessment or call (301) 953-4140. You can read more about the monitoring and maintenance service first. If your purchase involves the Maryland Solar Access Program, ask any installer whether it is on the program’s contractor list.

This guide is general information, not legal, tax, or financial advice.

Sources (18)

1. National Laboratory of the Rockies (formerly National Renewable Energy Laboratory) and partners, Best Practices for Operation and Maintenance of Photovoltaic and Energy Storage Systems, third edition, published December 2018, section 6.7.1 (product and output warranties), https://docs.nlr.gov/docs/fy19osti/73822.pdf; read October 25, 2026. ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰ ↩¹¹ ↩¹²

2. Maryland Energy Administration (with Clean Energy States Alliance), A Maryland Consumer’s Guide to Solar, published January 2018, “Warranties,” printed page 43, https://energy.maryland.gov/residential/Documents/A%20Maryland%20Consumers%20Guide%20to%20Solar%20LR72dpi.pdf; read October 25, 2026. ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰ ↩¹¹ ↩¹² ↩¹³ ↩¹⁴ ↩¹⁵

3. Same source as ¹, section 5.3 (roof maintenance related to the solar system, roof warranty issues, overburden waiver). ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸

4. Same source as ², printed page 43 (panel, inverter and racking warranty ranges, installer responsibility for incorrect installation, claim inspection). ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰ ↩¹¹ ↩¹²

5. Same source as ¹, section 6.7.1 (reasons financiers distrust manufacturer warranties: voiding, closures, proof, labor, remedy options, cash value). ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰ ↩¹¹

6. Same source as ², printed pages 34, 35 and 38 (contract warranties, subcontractors, lease questions, claims and insurance). ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸

7. Federal Trade Commission, Solar Power for Your Home, https://consumer.ftc.gov/articles/solar-power-your-home; page dated April 2022; archived copy captured October 15, 2026 by the Internet Archive (https://web.archive.org/web/20261015121826/https://consumer.ftc.gov/articles/solar-power-your-home), which is the copy read on October 25, 2026. ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶

8. Maryland Energy Administration, FY27 Consumer Protection Policy for the Maryland Solar Access Program (Funding Opportunity Announcement Attachment A), section 3.3 “Warranty and Maintenance,” issued July 29, 2026, https://energy.maryland.gov/residential/SiteAssets/Pages/incentives/Maryland-Solar-Access-Program/FOA%20Attachment%20A%20-%20FY27%20MSAP%20Consumer%20Protection%20Policy%20-%20Issued%207.29.26.pdf; read October 25, 2026. ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸

9. Same source as ¹, section 10.1 (installer and equipment warranty terms, upkeep conditions, how output terms are defined) and section 5.9.6 (battery warranty temperature conditions). ↩ ↩² ↩³ ↩⁴ ↩⁵

10. Same source as ², printed page 40 (natural degradation). ↩

11. Maryland General Assembly, Business Regulation Article, section 8-501(b) and (c) (home improvement contract requirements), https://mgaleg.maryland.gov/mgawebsite/Laws/StatuteText?article=gbr&section=8-501&enactments=false; current statute text, read October 25, 2026. ↩

12. Same source as ⁸, section 3.5 “Roof Condition.” ↩ ↩²

13. Maryland Department of Labor, Home Improvement Commission, Guaranty Fund frequently asked questions, https://labor.maryland.gov/license/mhic/mhicfaqgf.shtml; undated, current page read October 25, 2026. ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰ ↩¹¹ ↩¹² ↩¹³ ↩¹⁴

14. U.S. Department of Energy, A Consumer’s Guide to Buying a House with Solar Panels, https://www.energy.gov/cmei/systems/consumers-guide-buying-house-solar-panels; undated, current page read October 25, 2026. ↩ ↩²

15. Maryland Department of Labor, Home Improvement Commission, Understanding Maryland’s Licensing Requirements for Green Technology, https://labor.maryland.gov/license/mhic/mhicgreen.shtml; undated, current page read October 25, 2026. ↩ ↩²

16. Maryland General Assembly, Business Regulation Article, section 8-401 (“actual loss”), https://mgaleg.maryland.gov/mgawebsite/Laws/StatuteText?article=gbr&section=8-401&enactments=false; current statute text, read October 25, 2026. ↩

17. Same source as ¹, section 6.10 (warranty transfer on a change of ownership). ↩ ↩² ↩³

18. Soleil Energy, Monitoring & O&M, https://soleilenergycorp.com/renewable-energy/monitoring-and-om/; undated, current page read October 25, 2026. ↩