Chimney service
Chimney Flashing Repair
The metal joint where the chimney meets the roof, resealed or replaced properly. The first place to look when water appears indoors.
If someone has already been at it with a tube of roofing tar, the repair now costs more.
Flashing is two pieces of metal doing one job. Step flashing lies under the shingles and turns up against the brick; counter-flashing is cut into a mortar joint and folds down over it, so water running down the brick is thrown out onto the roof rather than behind the metal. Both have to be right. Chimney flashing repair means restoring that two-part detail — not smearing sealant across the joint, which is what tar does and why tarred flashing leaks again within two or three seasons.
The joint that fails first
Where the roof meets the brick
Two pieces of metal doing one job: step flashing under the shingles, counter-flashing cut into the mortar above it. Both have to be right.
On this pageSigns you need this3 sections+2
Signs you need chimney flashing repair
Flashing lifted away from the brick
The counter-flashing has pulled out of its mortar joint, or the sealant bead behind it has failed. You can usually see daylight or slide a card into the gap.
Black roofing tar smeared over the joint
Someone's earlier repair. Tar shrinks and cracks as it ages, and it has to be cut and scraped off before anything proper can be done, which is why it makes the eventual job more expensive.
A stain on the ceiling near the chimney
Flashing is the first suspect for any chimney leak, because it is the most common entry point on any chimney. It is also the cheapest of the five to rule out.
The leak only appears in wind-driven rain
Failed flashing often sheds vertical rain fine and lets water past when it is being pushed sideways. That is why the leak seems to come and go with the weather.
Damaged shingles around the chimney base
Water running where it should not have been eventually rots the deck under the shingles. Once that has started, the flashing repair includes roof work.
Rust in the firebox with no other cause
Water entering at the flashing can run down inside the structure and reach the firebox. Rust in a capped chimney with a sound crown points here.
How the visit works
The same four steps every time, whatever the repair turns out to be.
- 01
Inspection first, always
A look at the crown, cap, flashing and exterior masonry, then the flue, damper and firebox — with a camera where the job calls for a level 2 scan. Whatever needs work gets shown to you, not just described.
- 02
A written estimate before anything
Scope, price and what is not included, in writing. Nothing starts until you approve it, and an emergency is not a reason to skip this step.
- 03
The work itself
Matched materials and the manufacturer's spec, not whatever is on the van. Drop cloths down, and the room left as it was found.
- 04
Verification and a report
A second scan after the work, and written findings you can keep, hand to an inspector, or send to an insurer.
The jobs this actually includes
Not every job on this list is equally urgent, so they are ordered that way. A cracked liner stops you using the fireplace tonight; waterproofing can wait for a dry week.
The job — most urgent first
What it involves
On site
Cricket or saddle fitting
StructuralA small peaked structure on the upslope side that splits water around the chimney. Code calls for one on wide chimneys, and their absence is why the back of a wide stack leaks repeatedly.
On site: 1–2 days
Full step and counter-flashing replacement
Stops waterNew step flashing woven into the shingle courses and new counter-flashing cut into a fresh reglet in the mortar joint. The proper repair, and the only one with a real lifespan.
On site: About a day
Removing a tar patch and repairing underneath
Stops waterCutting off old roofing cement to find out what is actually under it. Usually flashing that could have been reused before the tar went on and cannot now.
On site: About a day
Reglet and counter-flashing reseal
Stops waterWhere the metal is sound but has worked loose: the joint is raked out, the flashing reset and repointed, and sealed with a polyurethane made for masonry rather than a general sealant.
On site: Half a day
Flashing with a roof replacement
PreventiveFlashing gets replaced when the roof does, not reused. A new roof around old flashing is the most predictable future leak on a house, and the cheapest moment to avoid it.
On site: Half a day
Times are for the work itself, not for scheduling. Masonry needs roughly 40°F to cure properly, which is what limits this work in a northern winter rather than whether a crew is free.
Why chimney flashing repair quotes vary so much
- Whether the metal can be reused or has to be fully replaced
- Whether tar or roofing cement has to be cut off first
- Roof pitch and height, and the roof covering — slate and tile are not shingle
- Whether the deck underneath has been damaged by long-term water
- Whether a cricket is needed on the upslope side
Resetting and resealing sound counter-flashing is a half-day job at the low end of chimney work. Full replacement of step and counter-flashing is about a day. What raises it beyond that is cutting off old tar, damaged decking, or a cricket that should have been there from the start. It is still one of the cheapest ways to stop a chimney leak.
The people behind every visit
Founded by Ryan Carter in 2019. Every page you read here is reviewed by Ethan Miller, our chimney specialist. A written estimate before any work, and the findings in writing whether or not anything needs doing.
More about who we are →
The VIO Standard
- A written estimate first
- License and insurance checked
- Nothing starts without your OK
Common questions
Why does chimney flashing leak?
Because it is a moving joint between two materials that move differently. Brick and roof deck expand and contract at different rates through every temperature swing, and the metal in between takes the strain. Add freeze-thaw working at the mortar joint the counter-flashing sits in, and eventually the seal opens. It is not a defect so much as the part of a roof with the shortest natural life, which is why it is the first place anyone should look at a chimney leak.
Can I just use roofing tar on chimney flashing?
You can, and it will hold for a season or two, and it will cost you more in the end. Roofing cement shrinks as it cures and keeps shrinking as it ages, so it pulls away from the brick and cracks — usually somewhere you cannot see. Worse, it has to be cut and scraped off before a proper repair can be made, and it often ruins flashing that could otherwise have been reset. A tarred chimney is a more expensive repair than one nobody touched.
How much does chimney flashing repair cost?
Resetting and resealing counter-flashing that is still sound is a half day and one of the cheaper jobs on a roof. Full replacement of both layers is around a day. The number moves when old tar has to come off, when the deck under the shingles has rotted from long-term water, or when a cricket is needed on a wide chimney. Even at the top of that range it is far cheaper than the interior repairs a long-running leak causes.
Should flashing be replaced when the roof is replaced?
Yes, and it is worth insisting on. Reusing flashing on a new roof is a common cost-saving and it is the single most predictable future leak on the house — the new shingles will outlast the old metal by decades. The extra on a roofing quote is small, and the alternative is paying for roof work twice to reach the same joint.
What is a chimney cricket and do I need one?
A cricket is a small peaked structure built on the upslope side of a chimney, splitting water and debris around it rather than letting them pile against the back. Code generally requires one where the chimney is wider than 30 inches across the slope. If you have a wide chimney with no cricket and the back keeps leaking however many times the flashing is redone, that is the reason, and no amount of sealant will substitute for it.
let's get it on the calendar.
Tell us your ZIP code and what you need. The pro who covers it quotes the job in writing, and nothing starts until you approve the number.