Roof Flashing Repair
Roof flashing is the thin metal that seals the joints where the roof meets a chimney, wall, vent or skylight. When it lifts, rusts or its sealant cracks, water runs behind it and shows up as ceiling stains. Most flashing repairs cost about $200 to $1,000; re-flashing a chimney is often $500 to $1,800.
Typical pro cost
$200 to $1,800
- Urgency
- Fix this week
- DIY difficulty
- Hard
- Time to fix
- 2 to 6 hours (pro)
- Prices
- US typical range
Last reviewed October 2026
Signs it's this problem
- Ceiling stains near a chimney, skylight or wall
- Rust, gaps or bent metal around roof joints
- Cracked or missing sealant along flashing edges
- Water marks on attic rafters near a chimney or vent
- Leaks that appear only in wind-driven rain
Common causes
Dried-out sealant
Caulk and roofing cement crack after a few years in the sun and let water in.
Loose or lifted metal
Wind and thermal movement pull nails loose and lift flashing edges.
Rust and corrosion
Old galvanized steel flashing rusts through, especially where debris sits.
Poor installation
Missing step flashing or face-nailed flashing is a common cause of leaks.
Chimney movement
Settling chimneys pull away from the roof and open the joint.
How to fix it, step by step
- 1
From inside, find the highest point of the stain and check the attic above it with a flashlight.
- 2
From the ground, use binoculars to look at the flashing around chimneys, walls, vents and skylights.
- 3
If you can work safely on a low-slope roof, reseal small gaps with roofing sealant rated for your flashing metal.
- 4
Refasten loose flashing with roofing nails or screws and cover the heads with sealant.
- 5
If metal is rusted through or step flashing is missing, have a roofer replace the flashing and nearby shingles.
- 6
After the repair, watch the stain through a few storms before repainting the ceiling.
Tools and materials
- Binoculars
- Flashlight
- Roofing sealant and caulk gun
- Roofing nails or screws
Approximate DIY cost: $20 to $60
Call a pro when
- Chimney or skylight flashing that needs replacing
- Steep or two-story roofs
- Wet or soft roof decking near the leak
Roof Flashing Repair cost
| Job | Typical cost |
|---|---|
| Reseal flashing (small repair) | $200–$500 |
| Replace step flashing along a wall | $300–$1,000 |
| Re-flash a chimney | $500–$1,800 |
| Replace a pipe vent boot | $150–$400 |
| Skylight flashing kit, installed | $300–$900 |
Ranges are typical US prices compiled by FixHomeCost. Prices vary by region, home and contractor, so compare 2–3 local quotes.
Common questions
How long does roof flashing last?
Metal flashing often lasts as long as the roof, 20 to 30 years or more, but the sealant around it may need attention every few years.
Can I just caulk roof flashing?
Caulk can stop a small leak for a while, but it is a temporary fix. Rusted or missing flashing needs to be replaced.
Is flashing replaced with a new roof?
It should be. Ask any roofing contractor whether new flashing is included in the quote.
Does insurance cover flashing repair?
Storm damage that tears flashing loose is usually covered. Worn sealant and rust are usually treated as maintenance.
Related guides
This is general information, not a professional inspection. See how we research costs.