A roof that will need replacing within about 10 to 15 years is often better replaced before the panels go on, or at the same time. Maryland’s 2018 consumer guide says panels on such a roof may not make financial sense, because they have to come off for the reroof. Get a written roof inspection first.1,2
How old is too old for solar?
No single age rules a roof out. The Maryland Energy Administration (MEA) guide from January 2018 says panels may not make financial sense on a roof needing replacement within 10 to 15 years, and that the roof should be “reasonably new and in good condition.” The U.S. Department of Energy (DOE) says to weigh roof age against time to replacement.1,3
Treat 10 to 15 years as a starting point for the inspection conversation, not a verdict. A young roof with storm damage fails the test. An older roof in good shape may pass.
Material matters too. A 2021 DOE article says a roof lasts anywhere from 20 to 50 years depending on materials, and that solar panels last about 25 to 30 years.4 Put those side by side and a roof with 10 to 15 years left will probably need replacing while the panels still work.
How do you find your roof’s age and remaining life?
Start with paper records, then bring in a professional. DOE says your local government should have a record of when it issued the building permit, and that a solar installer, roofing expert or structural engineer can judge whether the roof suits solar.5
- Ask your county or town permitting office for the roof’s permit history. Not every reroof leaves a record, so a blank doesn’t mean the roof is new.
- Dig out roofing invoices, warranty papers and any inspection report from when you bought the house.
- Note the shingle type if the paperwork names it, because materials age differently.4
- Hire a roofing professional to inspect the roof and write down its condition, any repairs needed and a remaining-life estimate. The MEA guide advises having the roof professionally evaluated before panels go on.1
- Hand that written report to every solar company that bids, and have each say in writing whether it agrees.
If the paperwork and the inspector disagree, go with the inspection. Records show when the roof went on. They can’t show how it has aged.
Is it cheaper to replace the roof and add solar together?
It can be, mainly because you skip paying to take panels down and put them back later. The 2018 MEA guide says that removal and reinstallation “may cost 20 percent or more of the original installation cost.”2 DOE’s 2021 article gives national averages from National Renewable Energy Laboratory (NREL) researchers, below. None is a Maryland quote.4
A 2018 NREL cost model points to one reason a combined job can cost less. In its “visionary” modeled pathway, which assumes an integrated solar-and-roofing product, combining the two kinds of work cuts truck rolls and crew-hours spent on site.6 That describes a business setup, not a price for your house.
Soleil Energy doesn’t publish prices. A quote follows a consultation that looks at your roof’s layout, age, condition and shade.7 Whoever you talk to, ask for the roof and the solar priced separately and together, then compare.
| Option | What happens | Cost exposure | Fits best when |
|---|---|---|---|
| Replace the roof, then install solar | Roofing finishes first; panels go on the new roofing | You pay for the roof up front | The roof is near the 10 to 15 year mark1 |
| Replace the roof and install solar together | One plan covers both jobs | Avoids a later remove-and-reinstall charge4 | You want both done now |
| Install solar now, reroof later | Panels come off for the reroof and go back on | Removal and reinstallation, possibly 20 percent or more of the original cost2 | The roof has long life left |
| Ground-mounted panels or community solar | Panels sit off the roof, or you join a shared array | Depends on the site or program | The roof is poor or unsuitable1 |
Leasing or buying power through a power purchase agreement changes the question. The MEA guide lists “who is responsible for removing and reinstalling the solar system if the roof needs to be repaired or replaced” as something to settle before you sign.8 For more on what to check before signing, see solar scams and red flags.
How does a combined roof and solar job run?
The roofer and solar installer need to coordinate mounts and flashing. Some mounts can go in before the finished roof covering, so the roofer can flash around them.9 The contract should spell out the sequence. Maryland’s Business Regulation Article, Section 8-501, says a home improvement contract must contain the approximate dates when the work will begin and be substantially completed.10
A combined project makes sense in this order:
- Roof inspection and a written remaining-life estimate.
- A decision on what the roof needs: repair, replacement or nothing yet.
- Permit checks for the roofing and for the solar, with the permitting office that covers your address.
- Roofing work, with mounts and flashing coordinated before the panels go on.9
- Solar design, permits and installation on the finished roof.
- Final inspections and approvals.
The weak spot is the joint where a mount passes through the new roofing. Pin down in writing who flashes and seals each attachment and who stands behind it if water gets in. The MEA guide says warranties should cover equipment and workmanship, and should include warranties for any damage to the roof during installation, if applicable.8 If a leak shows up later, roof leak under solar panels explains who to call and what to document.
Which Maryland rules cover a roofing and solar contract?
Three rules shape the paperwork: contractor licensing, the contents of the contract, and a wildlife barrier on roof-mounted solar. Check each company’s license, confirm the contract states the work and the dates, and find out which permits your address needs from the local office.11,10,12
| Rule | What the law says |
|---|---|
| License requirement, Business Regulation section 8-301 | Except as the title otherwise provides, a person must have a salesperson license or a contractor license whenever the person sells a home improvement in Maryland, and the section lists exceptions. To check a company, use the Maryland Home Improvement Commission’s license search.11 |
| Contract contents, section 8-501 | Each contract shall be in writing and legible and signed by each party. Among other items, it shall contain the approximate start and substantial completion dates, a description of the work and materials, and the agreed consideration (the price).10 |
| Wildlife barrier, section 8-501(f) | A contract for solar on a building’s roof shall include a barrier against wildlife intrusion, unless the customer has waived it after being informed of the barrier’s cost and the risks of not installing it. The Commission’s notice says this took effect June 1, 2024.12 |
| Permits | Rules differ by county and town, and some roofing work needs no permit. Confirm what your office requires. Roofing and solar permits are separate checks. |
The barrier protects the roof you just paid for, so read that clause before you waive it. If a contractor says no permit is needed, get that in writing along with the name of the office that said so. For the county side, see our permit guides for Prince George’s County and Montgomery County.
Does the federal solar tax credit change the decision?
Not for a system installed now. As of October 25, 2026, section 25D doesn’t apply to expenditures made after December 31, 2025, and an expenditure counts as made when the original installation is completed. The IRS says paying by that date doesn’t help if the installation finishes later.13,14
A guide that subtracts the 25D credit from a 2026 install is out of date. Confirm your own situation with a qualified professional, and see the federal solar tax credit in 2026 for more.
When does the roof-first advice change?
The 10 to 15 year cutoff shifts when the roof, the structure or the contract changes the facts. Most of these exceptions come from the 2018 MEA guide, so read them as that guide’s cautions, not hard limits. A damaged or leaking roof comes first whatever its age.
The guide wants a roof in good condition.1 Some roofs can’t carry the weight of panels, and the guide lists ground-mounted panels as an option. DOE says a solar installer, roofing expert or structural engineer can judge suitability.1,5 Slate is a special case: the guide says panels on slate are generally not recommended because of the potential to damage the slate.1 Metal roofs typically last longer than asphalt, but the guide still says to check the roof’s condition so you know when it will need replacing.1 And with a leased or financed system, who pays to remove and reinstall depends on the agreement, so read it before anyone touches the roof.8
Only a qualified professional who inspects your roof can say how much life it has left.
What should you do before you collect solar bids?
Get the roof inspected, then hand the written report to every bidder. If the report puts replacement inside 10 to 15 years, price the combined job. If it shows long life, price solar alone and keep the report for later.
Bring the roof’s age, your inspector’s estimate and any permit records to the first conversation. What to expect at a solar consultation covers the visit itself. To talk through your plans, book a free consultation and put your roof’s age and condition in the message, or call (301) 953-4140.
Solar savings and incentive eligibility depend on your roof, your usage, your utility, and your tax situation. Incentive programs change and some have limited funding. We are not tax advisors — we will review your bill with you and tell you what you may qualify for. Confirm any tax credit with a qualified tax professional.
Sources (14)
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Maryland Energy Administration and Clean Energy States Alliance, “A Maryland Consumer’s Guide to Solar,” January 2018, page 20 (roofing material, roof age and condition); PDF read October 25, 2026. https://energy.maryland.gov/residential/Documents/A%20Maryland%20Consumers%20Guide%20to%20Solar%20LR72dpi.pdf ↩ ↩2 ↩3 ↩4 ↩5 ↩6 ↩7 ↩8 ↩9 ↩10 ↩11 ↩12
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Same source as 1, page 20 (removal and reinstallation cost); read October 25, 2026. ↩ ↩2 ↩3
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U.S. Department of Energy, “Homeowner’s Guide to Solar,” published June 16, 2016; page last modified May 15, 2026; read October 25, 2026. https://www.energy.gov/cmei/systems/homeowners-guide-solar ↩ ↩2
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U.S. Department of Energy, “Replacing Your Roof? It’s a Great Time to Add Solar,” July 28, 2021; page last modified May 15, 2026; read October 25, 2026. Figures cite National Renewable Energy Laboratory researchers as national averages. https://www.energy.gov/eere/solar/articles/replacing-your-roof-its-great-time-add-solar ↩ ↩2 ↩3 ↩4 ↩5 ↩6 ↩7 ↩8 ↩9
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U.S. Department of Energy, “Walk Me Through It: A Step-By-Step Guide for Consumers Going Solar,” published August 4, 2021; page last modified May 15, 2026; read October 25, 2026. https://www.energy.gov/cmei/systems/articles/walk-me-through-it-step-step-guide-consumers-going-solar ↩ ↩2
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National Renewable Energy Laboratory, “Cost-Reduction Roadmap for Residential Solar Photovoltaics (PV), 2017-2030,” NREL/TP-6A20-70748, January 2018, page 11; PDF read October 25, 2026. The sentence describes the “visionary” modeled pathway. A modeled pathway, not a price. https://docs.nlr.gov/docs/fy18osti/70748.pdf ↩
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Soleil Energy, “Residential solar” page (FAQ section and “What will it cost?” answer) and “Frequently asked questions” page, current pages (undated), read October 25, 2026. https://soleilenergycorp.com/renewable-energy/residential-solar/ and https://soleilenergycorp.com/faq/ ↩
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Same source as 1, pages 34 and 35 (warranty and lease questions); read October 25, 2026. ↩ ↩2 ↩3
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U.S. Department of Energy, Building America Solution Center, Roof Anchor System for Solar Panels (current undated page), https://basc.pnnl.gov/resource-guides/roof-anchor-system-solar-panels; read October 26, 2026. The roof-penetrations section describes installing standoff brackets before the finished roof and coordinating roofers and solar installers. ↩ ↩2
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Maryland General Assembly, Business Regulation Article section 8-501, subsections (b) and (c), current online text read October 25, 2026. https://mgaleg.maryland.gov/mgawebsite/Laws/StatuteText?article=gbr§ion=8-501&enactments=false ↩ ↩2 ↩3
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Maryland General Assembly, Business Regulation Article section 8-301, current online text read October 25, 2026. https://mgaleg.maryland.gov/mgawebsite/Laws/StatuteText?article=gbr§ion=8-301&enactments=false ↩ ↩2
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Maryland General Assembly, Business Regulation Article section 8-501(f), current online text read October 25, 2026; and Maryland Department of Labor, “Maryland Home Improvement Commission,” notice on rooftop solar contracts effective June 1, 2024, current page (undated), read October 25, 2026. https://labor.maryland.gov/license/mhic/ ↩ ↩2
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Internal Revenue Service, “FAQs for modification of sections 25C, 25D, 25E, 30C, 30D, 45L, 45W, and 179D under Public Law 119-21,” FS-2025-05, August 21, 2025, question 7; page read October 25, 2026. https://www.irs.gov/newsroom/faqs-for-modification-of-sections-25c-25d-25e-30c-30d-45l-45w-and-179d-under-public-law-119-21-139-stat-72-july-4-2025-commonly-known-as-the-one-big-beautiful-bill-obbb ↩
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U.S. Code, 26 U.S.C. section 25D(e)(8)(A) and (h), as amended by Public Law 119-21 section 70506 (July 4, 2025), Cornell Legal Information Institute, current text (undated page), read October 25, 2026. ↩
