Does your chimney leak when it rains? If so, you might have a problem with your flashing. Chimney flashing is the material that forms a waterproof seal on your chimney, protecting it from water damage and leaks. It is found at the point where your roof meets your chimney and is usually made of metal or vinyl. If your chimney leaks when it rains, keep reading to learn more about chimney flashing repair and sealing.