The answer to 'flashing sagging' is that sagging flashing is a common roofing issue caused by improper installation, weathering, or damage. Flashing is the thin metal or plastic material used to seal joints and edges on a roof, preventing water leaks. When flashing starts to sag, it can lead to water intrusion and roof damage.
Some common causes of sagging flashing include nails or screws working loose over time, poor initial installation, or the flashing simply wearing out after years of exposure to the elements. Symptoms include visible gaps or spaces at the flashing edges, water stains, and leaks. To fix sagging flashing, the best solution is usually to remove and replace the damaged flashing, which is a job best left to professional roofers unless the homeowner has significant experience with roof repairs.