Severe storms are a regular part of life in Missouri and Illinois. High winds, hail, and heavy rain can place enormous stress on commercial roofing systems. While a roof may appear solid from a distance, certain areas are naturally more vulnerable during extreme weather.
Understanding where damage tends to occur can help building owners and property managers identify problems early and prevent more serious issues later.
Here are the areas of a commercial roof that storms tend to target first.
Roof Edges and Perimeter Metal
The edges of a commercial roof experience the strongest wind forces during a storm. As wind moves across a building, pressure changes along the perimeter can create uplift that stresses edge metal, coping, and termination bars.
If edge components loosen or fail, wind can begin to lift sections of the roofing membrane itself. Once this process starts, damage can escalate quickly.
After a major storm, it is common to find:
Loose or bent edge metal
Fasteners pulled away from the roof deck
Separation where the membrane meets the roof edge
Because the perimeter is the first line of defense, maintaining these components is critical to overall roof performance.
Flashing Around Roof Penetrations
Commercial roofs contain numerous penetrations for equipment and building systems, including:
HVAC units
Vent pipes
Exhaust fans
Electrical conduits
Each penetration requires flashing to keep water from entering the roofing system. During storms, wind-driven rain and debris can stress these sealed areas.
Over time, flashing may crack, loosen, or separate, allowing water to enter around the base of the penetration.
These are often the first places leaks develop after a severe weather event.
Parapet Walls and Coping
Many commercial buildings use parapet walls to extend the roofline above the surface of the roof. While these structures provide architectural benefits, they can also become points of vulnerability during storms.
High winds can loosen coping caps and metal coverings, creating openings where water can enter behind the roofing system.
Once water penetrates these areas, it can travel into wall assemblies or roofing insulation, making the damage harder to detect.
Drains, Scuppers, and Low Areas
Heavy rainfall during storms can overwhelm roof drainage systems. Leaves, debris, and storm material often collect near drains and scuppers, preventing water from flowing properly off the roof.
When drainage becomes blocked, water begins to pond in low areas.
Standing water places additional stress on the roofing membrane and can accelerate deterioration, particularly if moisture begins working its way into the insulation layer below.
Small Weak Points Become Big Problems
Storm damage rarely begins with a catastrophic failure. In many cases, the process starts with a small weakness in one of these vulnerable areas.
A loose fastener, a slightly lifted flashing edge, or a blocked drain may not seem significant at first. But under the pressure of wind and heavy rain, those small issues can quickly turn into larger roofing problems.
Routine inspections help identify these vulnerable points before severe weather exposes them.
A Proactive Approach to Storm Season
Commercial roofs are designed to withstand challenging weather conditions, but they perform best when small issues are addressed early.
Regular inspections — especially before and after major storms — allow building owners to identify potential vulnerabilities and protect the long-term performance of their roofing systems.
At Jewett Roofing, we work with commercial property owners throughout Missouri and Illinois to assess roof conditions and address storm-related damage before it leads to costly repairs.
Reliable commercial roofing inspections and repairs when you need them most.
