Will Solar Panels Put Holes in My Commercial Roof?
If you’re thinking about putting solar on your building, you’re probably excited about the savings… and a little nervous about what it does to your roof.
That makes sense. A commercial roof is not the place you want “surprises,” and the first question most property owners ask is the most practical one:
“Are you going to poke holes in my roof?”
I’m Cody. Before I worked at Weather Shield Roofing Systems, I sold solar for about five years. Now I sell roofs and help building owners think through solar the right way, especially when the roof is part of the equation. Weather Shield has been protecting commercial buildings for over 45 years, so we’ve seen what works, what fails, and what costs people real money later.
Let’s answer the big question.
Direct answer: It depends on your roof type and mounting system
Solar panels do not always require roof penetrations.
- On many commercial flat roofs (like TPO and EPDM), solar is often installed using a ballasted system, which can avoid penetrations entirely.
- On other roof types — especially some metal roofs — penetrations may be required unless you have the right kind of metal roof (like standing seam).
Here’s the simple breakdown.
Do solar panels penetrate a TPO or EPDM roof?
Usually, no — not if the system is designed as a ballasted array.
A ballasted solar array is a racking system that sits on the roof and is held down using weight (often concrete blocks). Instead of drilling into the roof, the system relies on engineering, wind-load calculations, and ballast weight to keep it secure.
Why building owners like ballasted solar on flat roofs
- No (or minimal) penetrations through the membrane
- Faster installation in many cases
- Reduced leak risk compared to traditional anchored systems
Important truth: “No penetrations” doesn’t automatically mean “no roof risk”
Even without fasteners through the roof, solar still changes what your roof deals with day to day:
- Added foot traffic during install and service
- Concentrated weight in specific areas
- More components sitting directly on top of the membrane
That’s why roof inspection and long-term roof maintenance matter even more after solar goes on.
What about solar panels on a metal roof?
Metal roofs are where the conversation gets interesting.
Yes, solar can penetrate a metal roof — unless it’s standing seam.
If you’ve got a standing seam metal roof, many solar systems can use specialized clamps that grip the seams. That means:
- No drilling through panels
- No fasteners directly into the roof surface
- A cleaner install (when done correctly)
If it’s not standing seam, roof penetrations may be part of the design.
If solar doesn’t penetrate, can it still cause leaks?
It can, but not because solar is “bad.” It’s because roofs are systems, and systems don’t love surprises.
Even without penetrations, solar can increase leak risk because:
- More people are walking on the roof
- The membrane can get scuffed or damaged during install
- Rooftop drainage can be affected (especially if racking blocks water flow)
- Service techs may not treat the roof like a roof (they treat it like a platform)
This is one reason Weather Shield often recommends planned roof maintenance (like Max Life Roof Care) even more strongly when solar enters the picture.
How long do solar panels last?
In most cases, 25+ years is a fair expectation, and often closer to 30–35 years depending on the product, maintenance, and environment.
That matters because your roof needs to “play nice” with solar for decades.
If your roof has 8–10 good years left, but the solar system is meant to stay 25–30 years, you’ve got a mismatch. And mismatches are where budgets go to die.
Do I need a new roof before putting solar on?
This is where most people want a comforting answer — but here’s the honest one:
If your roof isn’t relatively new, it’s very likely you’ll need a reroof (or at least a serious roof plan) before solar goes on.
Here’s why:
- Roofs don’t stay “okay” forever
- Even if it looks fine from the ground, deterioration adds up
- Solar can make future roof replacement more expensive (because panels often must be removed and reinstalled)
A practical rule of thumb:
If your roof is within the last 5 years, you may be in great shape.
If it’s older than that, you should assume solar will force a more serious roof conversation.
If the roof may need replacement within 10 years, it’s usually smarter to address it now before solar locks you in.
That doesn’t mean “you must buy a roof.” It means you should avoid paying twice.
What should I do first if I’m considering solar on my roof?
Start with a roof inspection and an honest roof-life conversation.
If the roof truly has 20–30 years left, great — then solar becomes a cleaner conversation.
If the roof has less runway, the smartest path is usually:
1.) Roof assessment
2.) Roof replacement plan (if needed)
3.) Solar partner selection + design
4.) Install with the roof system in mind
5.) Ongoing roof maintenance (especially after solar)
Final thought
Solar can be a great investment — but the roof is the foundation of the whole deal. If you don’t treat the roof like part of the system, you can end up with unnecessary leak risk, premature replacement costs, and a solar project that becomes a headache instead of a win.
If you’re thinking about solar, start with the roof first. That’s the cleanest way to protect the building and protect the ROI.
If you want an honest evaluation of whether your roof is a good solar candidate (or whether you should reroof first),reach out to our team today!
Cody Bumbalough
Cody has served as an Account Manager since May 2025, playing a key role in delivering the high-level service that Weather Shield is known for. Based in Nashville, he guides commercial and residential clients through complex roofing projects with a consultative, solution-focused approach that prioritizes long-term value. Known for his attention to detail and clear communication, Cody ensures every project meets strict quality standards while keeping clients informed and confident. Whether coordinating inspections, managing maintenance programs, or resolving urgent leaks, he treats every roof as if it were our own—building trust and lasting partnerships along the way.
