What is a chimney liner and what does it do?
A chimney liner is the inner channel of a chimney — clay tile, stainless steel, or cast-in-place — that contains the exhaust, shields the surrounding masonry and framing from heat, and gives the flue the correct size to draft properly. It does three jobs at once. Every gas or wood insert we install gets a correctly sized liner, because the appliance depends on it.
Three jobs, one component
A liner keeps the byproducts of combustion inside the flue instead of letting them seep through masonry into your walls; it protects brick, mortar, and nearby wood framing from the heat of the exhaust; and it sizes the passage so the appliance drafts the way its maker intended.
Take any one of those away and you've got a problem — a fire risk, a carbon-monoxide risk, or a smoky, poor-drafting fireplace. Clay tile is the traditional masonry liner; stainless steel is what we run for inserts and relines.
Why inserts can't skip it
An open masonry flue is far too big for a sealed gas or wood insert. The oversized cavity never heats up enough to draft cleanly, exhaust stalls, and acidic condensate attacks the brick from the inside.
A properly sized stainless liner solves all of it — it gives the insert the tight, direct path it needs to breathe and vent. That's why a correctly sized chimney liner is part of how we do every insert, gas, wood, or pellet.
When an existing liner is the problem
In older Asheville and Canton homes we regularly find clay liners that are cracked, spalled, or missing entirely — sometimes an unlined chimney that never should have passed. A damaged liner leaks heat and gases where they don't belong.
Before we install or convert anything, we inspect the liner and reline it if it's compromised, then pull the permit and have the inspector confirm it. If your chimney's age worries you, call (828) 545-0525.
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