Repairing your leaky roof

Locating the Source of Your Roof Leak

1. Inspect for cracks, splits, tears, or any visible problems. If you find any, they most likely will represent a leak.
2. Inspect all roof penetrations (skylights, chimneys, roof vents, etc.), to see if roofing cement still adheres. Run a key or pen down a vertical surface. See if cement comes away from the surface. Any separation indicates a roof leak. Remember, 8 out of 10 roof leaks occur at a vertical penetration of the roof.
3. Check all places where dissimilar materials come together – where metal meets brick, shingles meet metal, etc. These surfaces expand and contract at different rates, and therefore tend to pull away from each other. Check for tight seals. A loose seal might indicate the source of your leak.
4. If all else fails, try locating the leak from the inside. Take a strong flashlight into the attic, and try following the leak uphill. Odds are, it will originate at some roof penetration. This will indicate your leak area.