Chimney Repair Cost Calculator

Where these numbers come from

The 3-2-10 rule, applied rather than quoted

A chimney has to finish 3 feet above where it passes through the roof and 2 feet above anything within 10 feet of it horizontally. Everybody states that; almost nobody applies it, and applying it gives an answer people find backwards. On a slope, the thing within 10 feet is the roof climbing towards the ridge, so the lower down the roof a chimney sits, the taller it has to be. At a 12:12 pitch the same chimney wants 10 feet where a 3:12 wants 4. ⚠️ This is trade practice, not a standard reproduced here, and your local building department is the authority. It is published because it is one of the very few things on a chimney quote a homeowner can check with a tape measure — and because a short chimney draws badly and pushes smoke back into the room on a windy day, which people usually blame on the fireplace.

Eight jobs, one name, a factor of twenty between them

From $901 for a rain cap to $20,891 for taking the stack down and rebuilding it. In between: waterproofing, a new crown, repointing, a stainless liner, the section above the roofline, and the firebox. ⚠️ Notice the order, because it is the useful part. The cheapest item on the page — a cap at $901 — prevents the mechanism behind almost everything below it. An open flue takes rain straight down into the masonry, and water freezing inside brickwork is what cracks crowns, blows out joints and spalls brick faces. If there is no cap on yours, that is where the money goes first. And before agreeing to the top of the range, get a second opinion: a chimney that has moved at its base has a foundation problem, and rebuilding the stack without fixing what is under it buys a few years at full price.

What decides the price is getting to it

Almost nothing on a chimney repair is material. Repointing 40 square feet uses a few bags of mortar and some diamond blades; what it costs is 18.6 trade hours of a mason working on a roof, plus the platform to do it from. A mason needs both hands, somewhere level to stand and somewhere to set mortar down, and none of those exist on a ladder — which is why scaffolding is a normal line rather than an upsell, and why the two cheapest jobs here are the two that genuinely can be done off a ladder. It is also why doing several things at once is worth asking about: the scaffold goes up once. If the crown is cracked and the joints have failed and there is no cap, having all three done on the same visit costs far less than three visits.

Why any of it matters, and where the wages come from

A chimney is the wall between a fire and the timber frame of a house, and the flue is how combustion gases leave rather than staying inside. U.S. Fire Administration, Heating fire safety covers heating fires, and CDC, Carbon Monoxide Poisoning Basics covers what a blocked or failed flue can do; both retrieved 2026-08-24. If you burn wood, EPA Burn Wise is worth reading for what actually reduces both smoke and creosote. ⚠️ None of that is advice from us: this page prices masonry, and a certified sweep with a camera is what tells you the condition of a flue. Wages from BLS OEWS, May 2025, for brickmasons and sheet metal workers, retrieved 2026-08-20, with benefit load from BLS ECEC. One declared substitution: much of the lining work is done by specialist chimney firms for which the BLS publishes no occupation, so the model uses sheet metal workers and says so. The required height at your pitch is 6 feet at the default settings, and repoint the mortar joints is what the reference figure prices.

Material prices

Modelled estimates, not sourced prices. No public, machine-readable source of US residential material prices exists, and we would rather say so than pretend otherwise. Each line carries its own uncertainty band. How we estimate them.

Contractor overhead and profit applied at 33–43% over direct cost. Data last reviewed 2026-08-24.