Chimney Flashing Repair Cost Calculator
Flashing is the metal-and-sealant joint where the chimney meets the roof. Price a reflash of the chimney only, not the roof field around it.
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Flashing is the metal-and-sealant joint where the chimney meets the roof — a leak here shows as a stain on the ceiling near the chimney. Reflashing is about $649 here. This covers the CHIMNEY flashing only, not the roof field (that’s a roofer).
Flashing is the layered metal-and-sealant joint that waterproofs the seam where the chimney passes through the roof. Done right it is two parts: step flashing woven into the roof courses and counter-flashing let into the masonry over the top of it. When it fails, the tell-tale sign is a water stain on the ceiling or in the attic right next to the chimney after rain — not out in the field of the roof.
The important scope line: this is the chimney’s flashing only. If the leak is out in the roof field, the shingles are shot, or the whole roof is near end of life, that is a roofer’s job, not a chimney reflash — pricing them together muddies the estimate. Keep this tool to the joint at the chimney.
Formula
Materials, labor and access, with a cushion:
total = (flashing materials + labor + access) × (1 + contingency)
Reflashing is mostly labor and getting to the roof; the metal and sealant are a small material line.
Worked example
An old caulk-only “flashing” job is leaking, so a proper step-and-counter flashing is installed. Materials come to $145, labor to strip the old work and reflash is $410, and access is $165. 10% contingency for a surprise soft roof deck at the joint:
(145 + 410 + 165) × 1.10 = 720 × 1.10 = $792
If the mason finds rotted decking under the old flashing, that carpentry is extra and belongs on a separate line — this tool stays on the flashing.
Real flashing vs a caulk smear, and where the scope ends
- Insist on two-piece flashing. A bead of roofing cement over the joint (“tar-and-pray”) is a temporary patch that fails within a season. Step plus counter-flashing let into the masonry is the durable fix.
- Confirm the leak is the flashing. A stain by the chimney can also come from a cracked crown, a bad cap or porous brick. Rule those out — the leak-repair tool helps — before you pay to reflash.
- Watch for a needed cricket. A wide chimney on the up-slope side often needs a small peaked saddle (cricket) to divert water around it; without one, flashing alone keeps failing.
- Keep the roof field separate. Deteriorated shingles or decking away from the chimney are a roofing job — do not fold them into a chimney flashing quote.
Reference table
Labeled planning bands for flashing and the crown work that often accompanies a chimney water problem:
| Masonry job | Typical planning band |
|---|---|
| Chimney flashing repair | $200–$1,500 |
| Crown repair / replacement | $200–$3,500 |
These are labeled planning bands — a reality check on a written quote, never a price you should expect to pay. Chimney cost swings with roof access and scaffolding, chimney height, roof pitch, how far the damage runs and local labor. Enter the real figures from your itemized quote above, and get that quote from a CSIA-certified sweep and a licensed, insured mason.