7 Common Roof Leak Sources

A roof leak rarely starts “in the middle of nowhere.” Water follows paths — and most leaks come from predictable locations where roofing materials connect, penetrate, or channel water.

1) Pipe boots (plumbing vents)

Those rubber collars dry out and crack. Small part, big problems.

2) Chimney flashing

Chimneys are a top leak source because brick/mortar and metal flashing expand differently with temperature changes. Gaps happen.

3) Roof valleys

Valleys carry heavy water flow. If debris collects or the valley wasn’t installed properly, water can push underneath shingles.

4) Skylights

Skylights can be fine — the leak is often the flashing system or aged seal points around it.

5) Step flashing at roof-to-wall areas

Anywhere a roof meets a vertical wall is a common weak point if flashing layers aren’t done correctly.

6) Gutters and drainage issues

Clogged gutters can cause backup and push water into fascia/soffit areas or under starter shingles.

7) Nail pops and fastener issues

A raised nail can break a seal and create a small but persistent pathway for water (especially during wind-driven rain).

What to do when you see a leak

Place a bucket, protect belongings, and take photos

• Avoid climbing on the roof (especially wet/icy)

• Call quickly — small leaks become mold, insulation damage, and rotten decking

If you’re seeing stains, drips, or damp attic insulation, Reynolds Roofing Exteriors & Coatings can pinpoint the source and recommend the best fix — repair or replacement — based on what’s actually happening.