Roof Valley Leak
Valleys carry more water than any other part of the roof, so worn shingles, debris dams and failed flashing there leak in heavy rain. Valley repairs typically cost $300–$1,500, and more if the valley has sagged or cracked.
Last reviewed September 2026
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Clear the valley
Leaves and debris in the V-shaped valley where two roof slopes meet make water back up under shingles. Clear it from a ladder at the eave if safe, then watch the next rain.
Signs it's this problem
- Stains below where two roof slopes meet
- Leaks mainly during heavy or long rain
- Debris or granules collecting in the valley
- Cracked or worn shingles along the valley line
Why it happens
Two slopes funnel their water into the valley. Leaves and grit build up, shingles wear faster, and nails placed too close to the valley centre or damaged valley flashing let water under the roofing.
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Safety: Valleys are steep and slippery, and water concentrates there. This is usually a job for a roofer.
Roof Valley Leak cost
| Job | Typical cost |
|---|---|
| Typical valley repair | $300–$1,500 |
| Replace valley flashing and nearby shingles | $300–$600 |
| Sagging or cracked valley | $1,000–$2,000 |
Got a quote? Check if it's fair
Typical professional price for this job: $300–$1,500
Common questions
Why do roof valleys leak?
They carry the water from two slopes, so any weakness, like worn shingles, debris dams or damaged flashing, is tested harder there than anywhere else on the roof.
Can I seal a valley myself?
Clearing debris is a safe DIY task. Sealing or replacing valley materials is best left to a roofer, because a poor repair can channel even more water under the roof.