The answer to 'why is my flashing leaking' is that there are several common causes, including improper installation, damage from weather or age, and sealant failure. Flashing is the thin metal or plastic material used to create a waterproof seal around roof features like chimneys, skylights, and vents. When the flashing is not installed correctly or becomes damaged over time, it can allow water to leak into your home.
Some key symptoms of leaking flashing include water stains on ceilings or walls, mold or mildew growth, and visible gaps or cracks in the flashing material. To fix the problem, you may need to re-seal the flashing with a high-quality sealant, replace damaged flashing, or in some cases, have a professional roofer completely re-install the flashing.