Flashing is thin metal (or sometimes rubber or other materials) installed where the roof meets another surface, to direct water away from the joint. Flashing repair means resetting, resealing or replacing it where it has lifted, rusted, cracked or pulled away. It’s one of the most common leak repairs there is.
Where flashing lives on a house
Every spot where water could sneak behind the roofing needs flashing. Knowing the names helps when a roofer explains what they found.
| Type | Where it is | How it commonly fails |
|---|---|---|
| Step flashing | Where a sloped roof meets a vertical wall, one piece per shingle course | Bent or lifted pieces; siding or sealant failure above |
| Counter-flashing | Embedded in a chimney or wall and lapping over base flashing | Mortar crumbling; sealant gone; rust |
| Valley flashing | Where two roof slopes meet in a V | Corrosion, punctures, debris buildup that backs water up |
| Chimney flashing | All four sides of a chimney, with a cricket on the high side if present | Cracked sealant, pulled-away sections, missing cricket |
| Vent and pipe flashing | Around plumbing vents, exhaust fans and other penetrations | Cracked rubber collars, loose bases |
| Drip edge | Along the eaves and rakes | Rust, gaps, shingles overhanging wrong |
Why flashing fails
Several things go wrong over time, and they often combine.
- Movement. Different materials expand and contract at different rates with heat. Over years that stress breaks sealants and pulls fasteners.
- Sealant aging. Caulk and roofing cement dry out and crack. Many “flashing leaks” are really failed sealant, not failed metal.
- Corrosion. Metal rusts or, where dissimilar metals touch, corrodes.
- Poor original installation. Missing counter-flashing, shortcuts at the chimney and unsealed fasteners can cause leaks within a few years of construction.
- Storm damage. Wind can lift or bend flashing, and falling branches can dent it.
Signs the flashing might be the problem
- Stains on the ceiling or wall right next to a chimney, wall or skylight
- Leaks that only occur with wind-driven rain
- Visible gaps, lifted edges or rust on metal pieces
- Cracked or missing sealant along a joint
- Staining on the exterior wall or siding where roof meets wall
Because water follows the flashing path, the stain can show up some distance from the damage. If you’re not sure, leak detection will confirm the source before any repair.
What repair looks like
Repair depends on what failed. It generally falls into one of three levels.
- Reseal.If the metal is sound and only the sealant has failed, the old material is removed, the joint cleaned, and new sealant applied. This is the quickest and cheapest fix, but it’s not forever. Sealant is a maintenance item.
- Reset or re-flash a section.Loose or bent pieces are removed and reinstalled, sometimes with new counter-flashing cut into the mortar of a chimney.
- Replace.Where the flashing is corroded or was installed wrong, a roofer may pull it and install new metal, which can mean lifting nearby shingles to weave the new pieces in correctly.
When shingles around the flashing are also worn, a roofer may recommend replacing those shingles at the same time, since the area has to be opened up anyway.
Be cautious of the caulk-and-go repair
Some quick fixes are just a bead of sealant over a failing joint. It can look like a repair and hold for a season, but if the underlying flashing is rusted or incorrectly built, the leak comes back. Ask the roofer whether they’re resealing or rebuilding, and why. If it’s a temporary measure, that’s fine, just call it what it is. See temporary leak sealing for when a stopgap makes sense.
Cost factors
We don’t set prices. Factors that influence them: how many flashing points are involved, whether it’s a chimney (which takes more work than a vent), roof pitch and height, how much of the surrounding roofing has to be lifted, and whether masonry work is involved. A single vent boot is a smaller job than rebuilding chimney flashing on a steep roof.
If you’re comparing options for roof leak repair near Cibolo, ask each roofer to describe exactly which pieces they’re resealing, resetting or replacing. Vague quotes make comparison impossible.
Questions people ask
Can flashing be repaired, or does it have to be replaced?
Either, depending on its condition. Sound metal with failed sealant can be resealed. Corroded, bent or wrongly installed flashing is better replaced.
Why does my roof leak around the chimney?
Chimneys are one of the most leak-prone parts of a roof. Common causes are failed sealant, loose counter-flashing, crumbling mortar and a missing cricket. A roofer can see which applies.
Is flashing leak repair covered by insurance?
Often it’s considered wear and tear, but storm damage may be treated differently. Your policy and insurer decide, and no roofer can decide that for you.
How long does flashing last?
The metal itself can last many years, while sealants wear out sooner. It varies a lot with materials, exposure and workmanship, so we won’t give a figure.
Can I fix flashing myself?
Resealing involves working on the roof, which is risky, and getting it wrong can make leaks worse. We recommend leaving it to a roofer.
Have a leak right now? Talk to a roofer.
One call connects you with an independent local roofing company. Tell them what you’re seeing and they’ll tell you what comes next.
Cibolo Peak Roofing is a referral service, not a roofing contractor. Roofing work is performed by independent local roofing companies, and any license, insurance, rating or warranty belongs to that company.