Why Are Skylights So Dangerous on Flat Commercial Roofs?
If you’re managing or investing in a commercial building, you might already know that skylights can be both a blessing and a hidden danger. While they let in natural light and help reduce energy costs, skylights on flat commercial roofs can be surprisingly dangerous—especially when it comes to safety, leaks, and long-term roof integrity.
At Weather Shield Roofing Systems, we’ve been helping businesses protect their buildings for over 40 years. So let’s break down why skylights pose risks, how you can manage them, and what you need to know to keep your people and your property safe.
What Makes Skylights So Risky on Flat Roofs?
Flat roofs present a unique set of challenges. Unlike sloped roofs that shed water quickly, flat commercial roofs tend to collect standing water, snow, and debris. Skylights are often installed as raised domes or flat lenses, but they create vulnerable points on your roof system.
Here’s why that’s a problem:
- Skylights are fall hazards: Unlike the roof membrane, skylights are not designed to support the weight of a person. Many look solid but are not impact-resistant. If a contractor, employee, or inspector accidentally steps on or trips near one, they could fall through.
- They age faster than the rest of your roof: UV exposure, hail, and temperature swings can crack or weaken skylight lenses over time, making them brittle and more prone to leaks or structural failure.
- Improperly sealed skylights cause roof leaks: The flashing around skylights is a common area for water intrusion, especially if the skylight was not installed properly or the sealant has deteriorated.
- They compromise the roof’s waterproofing: Every penetration in a flat roofing system increases the risk of failure. A skylight is a sizable opening, and if the roof membrane isn’t integrated perfectly with the skylight curb and flashing, it opens the door to water damage, insulation deterioration, and mold.
Can People Really Fall Through Skylights?
Yes, and sadly, it happens more often than you might think. One of the most dangerous aspects of skylights is that they can appear to be walkable, especially when they’re covered in snow, leaves, or dirt.
In fact, OSHA classifies skylights as “holes in the roof” for a reason. Without proper safety precautions like guardrails or protective screens, a skylight is a serious fall hazard. For facility managers, that means if someone is working on the roof—whether it’s a roofer, HVAC tech, or maintenance staff—you are liable for their safety.
Tip: If your building has skylights and no fall protection in place, this is an urgent safety issue. Consider installing skylight screens or rails that meet OSHA fall protection standards.
How Do Skylights Affect Roof Leaks and Maintenance?
Skylights are one of the most common sources of roof leaks on commercial flat roofs. Over time, flashing can pull away, gaskets can dry out, or cracks can form in the lens itself.
In our 40+ years of roof inspections, we often find that small, unnoticed skylight issues eventually lead to:
- Interior water damage and stained ceiling tiles
- Compromised insulation
- Mold growth in the roofing system
- Accelerated roof deterioration around the skylight opening
These problems don’t just affect your roof; they affect the value of your building and the health of the people inside. That’s why routine roof inspections—especially around roof penetrations like skylights—are so important.
Are There Safer Alternatives to Skylights on Commercial Roofs?
Natural light is valuable, and we understand the appeal of skylights. But if safety and longevity are top priorities, there are other ways to achieve similar benefits:
- Solar tubes or light wells: These provide natural light without large, vulnerable openings in the roof.
- Daylighting systems: Advanced systems with integrated flashing and dome designs may offer better leak protection but still require maintenance.
- Interior lighting upgrades: Modern LED systems with daylight simulation can mimic natural light without altering the roof structure.
If you already have skylights, proactive maintenance and inspections are key. And if you’re considering adding skylights to an existing roof, make sure you involve a commercial roofing expert to assess the risks and waterproofing details before making a decision.
What Can I Do to Make My Roof Safer if I Already Have Skylights?
Great question. If your building already has skylights, here are practical steps you can take today:
- Schedule a professional roof inspection focused on all skylight areas.
- Install OSHA-compliant fall protection like skylight cages or guardrails.
- Check flashing and seals regularly for signs of deterioration.
- Clean skylights frequently so their condition is visible, and they’re not mistaken for walkable areas.
- Educate your maintenance teams on the dangers of skylights and proper safety practices when accessing the roof.
At Weather Shield, we also offer Max Life™ Roof Care, a proactive maintenance program designed to extend roof lifespan and catch small issues—like skylight leaks—before they turn into big problems. Skylights don’t have to be a liability, but they do need consistent attention.
How Much Does It Cost to Fix Skylight Problems on Commercial Roofs?
It depends on the issue. Small repairs like resealing flashing may cost a few hundred dollars. Replacing a skylight, especially on an older roof, can cost significantly more—especially if surrounding roofing material has been damaged by leaks.
A full roof inspection can help you understand whether skylights are still safe and if it makes more sense to repair, replace, or remove them entirely. Sometimes, eliminating unnecessary skylights during a roof restoration project can actually reduce long-term costs and improve roof integrity.
Skylights may seem harmless, but on flat commercial roofs, they bring hidden dangers that can affect your roof’s performance, safety, and lifespan. At Weather Shield Roofing Systems, we’re here to help you navigate these challenges with honesty and expertise. If you’re unsure about the condition of your skylights or just want a professional opinion, let’s talk. We’ve spent over four decades helping businesses like yours protect their investments—and we’re always here to help.
Reach out to us here for a roof inspection or safety consultation.
Jordan Hester
Digital Marketing Strategist
Jordan Hester is a marketing and digital media professional with over five years of experience in strategy, visual media, and web design. A 2019 graduate of Hanover College, Jordan studied Art + Design and Business, blending creative vision with strategic thinking. In addition to expertise in marketing and digital strategy, Jordan brings extensive hands-on experience in photography, videography, and content creation—crafting compelling visuals and campaigns that engage and inspire.
