What are common failure patterns at roofing edges?

• A. Cracking due to UV exposure.
• B. Flow separation, turbulence, and pressure amplification.
• C. Dome formations.
• D. Enhanced wind uplift.

Answer: (B)

At roofing edges, abrupt geometry disrupts wind flow, causing flow separation and the formation of vortices and turbulence around parapets, eaves, and edge details. This turbulent flow creates local pressure variations—suction on the membrane and flashing, with pressure amplification in certain zones—that drive uplift and edge-related failures. This aerodynamic pattern directly explains why edge areas are common failure sites, such as membrane pull-out and flashing displacement leading to leaks. Other options describe phenomena that aren’t the primary edge failure mechanism—UV cracking is material aging, dome formations aren’t typical edge patterns, and simply stating enhanced wind uplift doesn’t capture the underlying flow-induced pressures at edges.