Your Flue Liner Is the Only Barrier Between Combustion Gases and Your Walls
A chimney liner contains combustion byproducts and protects your home's structure from heat transfer.
Oklahoma Chimney Sweep Pro installs and replaces chimney liners across Oklahoma City using a sizing-first process. We calculate liner diameter against appliance BTU output and flue height before a single foot of liner is ordered.
Oklahoma City's Older Neighborhoods and the Liner Problem Nobody Talks About
OKC's pre-1980 housing stock is full of original terra cotta tile liners that have never been replaced.
- Freeze-thaw chips the grout joints
- Heat stresses the tiles
- Tiles crack horizontally, joints open
- Carbon monoxide pathways form
Oklahoma City has a lot of homes built between 1940 and 1980. Many of those chimneys still have their original terra cotta tile liner - the clay tile system that was standard construction at the time. Those tiles were never designed to last a century.
Here's what most homeowners don't realize about clay tile liners: the problem isn't dramatic failure. It's slow degradation.
Oklahoma City's freeze-thaw cycles chip away at grout joints every winter. Summer heat and combustion heat combine to thermally stress the tiles themselves. Over decades, tiles crack horizontally. Mortar joints open. The flue that looked fine on the outside starts developing what technicians call carbon monoxide pathways - routes combustion gases take when a damaged liner allows migration through masonry voids rather than exiting cleanly at the flue termination.
Since 2016, our 10-person crew has assessed liner conditions in OKC homes across multiple decades of construction. The liner failures we find most often in older OKC homes aren't catastrophic collapses. They're quiet, incremental gaps that only show up under camera inspection.
How We Sized and Relined a 1960s OKC Home After an Appliance Swap
An appliance change is one of the most common reasons a liner must be replaced - and one of the most commonly overlooked.
From Oklahoma Chimney Sweep Pro's crew:I ran a liner assessment on a 1960s home in Oklahoma City a couple of years back. The homeowners had just installed a high-efficiency gas insert into what had been a wood-burning fireplace. The original terra cotta tile liner was intact - no visible cracking, no obvious damage. On paper, it looked fine.
But the liner diameter was wrong.
The original liner had been sized for an open wood-burning fireplace. Gas inserts are sealed appliances. They operate at lower flue temperatures and require a smaller liner cross-sectional area to maintain proper draft velocity. Running a gas insert through an oversized liner is what technicians call an appliance change trigger - the situation where an existing liner must be replaced because the new appliance requires a different liner diameter or material specification.
An oversized liner on a gas appliance lets flue gases cool before they exit. Cooled gases condense. Condensation creates acidic deposits inside the flue. Over a season or two, that turns into a deterioration cycle that accelerates liner failure.
We pulled the tile liner, conducted a liner sizing ratio calculation - that's the mathematical relationship between liner cross-sectional area, flue height, and BTU output - and installed a 4-inch stainless steel flexible liner with insulation wrap. The insert drafted cleanly on first burn. No condensation issues at the six-month follow-up.
- Tile liner intact, but the diameter was wrong
- Sizing ratio calculated before ordering
- Insulation wrap installed
- Clean draft, no condensation at six months
The homeowners didn't know there was a sizing problem. Most people don't. That's why we assess before we order.
Stainless Steel or Cast-in-Place - Here's How We Choose
The right liner material depends on your fuel type, flue geometry, and whether you're relining or resurfacing.
- 316 for gas appliances
- 304 for wood-burning
- Spray-applied resurfacing
- No full tear-out
We use two primary relining systems at Oklahoma Chimney Sweep Pro. For most residential jobs, a stainless steel flexible liner - corrugated metal inserted into the existing flue - is the most practical solution. We use 316-grade alloy for gas appliances and 304-grade for wood-burning applications. Material selection follows fuel type, not preference.
For flues where the tile is damaged but the flue geometry is still sound, we use HeatShield Cerfractory Liner - a spray-applied resurfacing system that restores the flue surface without a full tear-out. HeatShield is appropriate when a camera inspection confirms the surrounding masonry is intact and the tile damage is surface-level rather than structural.
We do not guess at which system to use. The camera inspection and liner sizing ratio assessment tell us which approach is correct for each specific flue.
Our Relining Standards at Oklahoma Chimney Sweep Pro
Every liner installation follows a consistent standard - no shortcuts based on job size.
Our relining work holds to the same standard on a small gas insert as it does on a full wood-burning overhaul.
- Liner sizing is calculated using actual flue height and appliance BTU output - not approximated from a chart
- Grade selection follows fuel type 316 stainless for gas, 304 for wood
- Insulation wrapping is standard where the flue runs through an exterior wall or unheated space
- Top termination fittings are stainless steel, correctly sized to the liner diameter
- All connections are sealed at the appliance and at the termination before any burn test
- Post-installation camera verification confirms liner seating and connection integrity
Oklahoma City building code compliance is confirmed before project close on every liner installation.
How We Size and Install Your New Liner
Our liner installation follows a four-step sequence - assessment, selection, installation, and verification.
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Step 1: Camera Inspection and Liner Sizing Assessment
We run a closed-circuit camera through the full length of the flue before any other work begins. We document tile condition, identify any carbon monoxide pathway risks, and confirm the flue dimensions. Then we calculate the liner sizing ratio - cross-sectional area against flue height and appliance BTU output. This step determines liner diameter and material grade.
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Step 2: Liner Selection and Procurement
Based on the assessment, we select the correct liner system - flexible stainless steel or HeatShield resurfacing - and order to the confirmed diameter. We don't pull a generic liner from stock and adjust on site.
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Step 3: Installation
For flexible stainless steel liners: we lower the liner from the crown, connect it to the appliance adapter at the firebox, seal both ends, and add insulation wrap where the design requires it. For HeatShield applications, we prep the flue surface and apply the system in accordance with manufacturer specifications.
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Step 4: Post-Installation Verification
We run a camera pass after installation to confirm seating, connection integrity, and clearance at the termination. Then we conduct a draft test with the appliance running. The job is closed only when the liner passes both the camera check and the live draft test.
1Camera passSeating, connections, termination clearance2Live draft testWith the appliance running
Oklahoma City Neighborhoods We Serve
Oklahoma Chimney Sweep Pro serves chimney relining customers across the Oklahoma City metro.
Our 10-person crew is based in Oklahoma City and handles liner installation and replacement projects throughout the OKC area. We work in established neighborhoods across the metro - including older residential areas where pre-1980 terra cotta tile liners are common - and in newer developments where gas insert conversions are driving appliance change upgrades.
Call us to confirm service availability at your address.
Chimney relining questions
How much does chimney relining cost in Oklahoma City?
Chimney relining costs vary based on liner type, flue length, and appliance configuration. Stainless steel flexible liner installations generally run less than cast-in-place systems. Insulation wrapping and termination fittings affect the final number. We provide written pricing after the camera inspection and liner sizing assessment - not before, because diameter determines material cost on every job.
What's the difference between a 304 and 316 stainless steel liner - and does it actually matter?
Yes, it matters. Grade 316 stainless resists acidic condensation from gas appliances better than 304. Grade 304 handles wood-burning heat better at lower cost. We select the alloy grade based on your fuel type - not personal preference. Using the wrong grade accelerates liner corrosion and shortens service life.
How long does chimney relining take from the first visit to a finished, tested liner?
Most residential relining jobs complete in one day. The camera inspection and sizing calculation happen first - sometimes on a separate visit. Installation, insulation wrapping, and post-installation camera verification follow. We don't close the job until the liner passes a live draft test with the appliance running.
Can my existing liner just be repaired instead of replaced?
Sometimes. HeatShield Cerfractory resurfacing works when tile damage is surface-level and the surrounding masonry is still structurally intact. Full liner replacement is required when tiles are fractured, geometry is compromised, or an appliance change demands a different diameter. The camera inspection determines which path is correct - we don't recommend replacement when resurfacing is appropriate.
Why does liner sizing matter - isn't standard diameter just standard diameter?
An incorrect liner diameter causes real problems. Undersized liners restrict draft and increase backdraft risk. Oversized liners let gases cool mid-flue, creating condensation and accelerating creosote buildup. We calculate the liner sizing ratio - cross-sectional area against flue height and BTU output - for every job. Sizing is math, not estimation.
My chimney tile looks intact - why would I need relining at all?
Cracked tiles often aren't visible without a camera. Oklahoma City's freeze-thaw cycles open mortar joints gradually over decades. A liner can look intact from the firebox opening while housing hairline fractures that create carbon monoxide pathways into wall cavities. Camera inspection is the only way to confirm liner condition - surface appearance is not reliable.
