Flue relining
Sweep & inspection
Caps & crowns
Masonry repair
Gas fireplace serviceLevel 1 sweep and inspection to the NFPA 211 annual standard - flue, crown, cap, and flashing checked and photographed
Chimney sweep logs do not sweep chimneys. They loosen some creosote - which then falls where a brush and vacuum still have to collect it.
DuraFlex Flue Liner Replacement: The Houston Owner’s Guide
We stock and install DuraFlex-compatible flue liner replacement parts across Houston, with most liner section swaps running between $350 and $900 fully installed depending on diameter and how many feet need replacing. If you call before 2 p.m. on a weekday, we can usually get a technician to your home within one to three business days, and we’ll confirm the exact DuraFlex part number before anything gets ordered. Most Houston homeowners discover a failed liner section two ways: either a Level 2 inspection with a camera finds a crack or separation at a seam, or they notice rust flakes and fine metal particles collecting in the firebox after a burn. Houston’s humidity accelerates corrosion on stainless liners that sit dormant through our damp spring and summer months, which is why we see more liner failures here than you’d expect in drier climates.
Which DuraFlex Models This Applies To
DuraFlex makes two main product lines that show up in Houston homes: the standard 316L stainless liner sections and the heavier 316Ti alloy used in their premium series. Both use the same twist-lock seam design, but the 316Ti sections have a thicker wall and hold up longer against the condensation that forms when a gas furnace vents through a chimney that was originally sized for a wood fireplace. The compatibility gotcha we run into constantly: DuraFlex changed the locking collar design around 2018, so a liner section bought before that year will not always mate cleanly with a new replacement section bought today. If your liner is older than that, we usually recommend swapping the entire run rather than trying to splice one new section into an older system. When we arrive, we check the stamped part number on the liner itself, not just the box it came in, because homeowners sometimes mix up the flex connector sections from a water heater with the actual flue liner.
For aftermarket parts, there are third-party manufacturers who claim DuraFlex compatibility, and some of them are fine. But we install genuine DuraFlex sections or, when a homeowner wants to spend less, the HeatShield or Gelco equivalents that we’ve verified fit the DuraFlex collar geometry. Hank Delano has done enough of these in Montrose and the Heights to tell you the same thing he tells every customer: the liner is the one part of your chimney you never want to cheap out on. It’s the only thing between a chimney fire and the framing around your chimney.
Styles & brands we work with





Signs Your DuraFlex Flue Liner Replacement Is Failing
- Rust scale in the firebox after burning. This usually means the inner wall of the liner has started pitting and flaking. In Houston’s humidity, a liner that sits unused from April through November can develop surface corrosion that breaks loose on the first hot fire of the season.
- A metallic rattle or ping when the chimney heats up. Stainless liners expand as they warm. If a seam has separated or a locking collar has worked loose, you’ll hear it. It’s not subtle once you know what to listen for.
- Water staining on the ceiling or wall near the chimney chase. A failed liner joint lets flue gases and condensation escape into the chase, and that moisture finds its way into drywall. By the time you see the stain, the liner has been leaking for a while.
- Smoke smell in the house after the fire is out. A liner with a crack or open seam can’t maintain proper draft, so smoke lingers and backs up into the living space. Houston’s low atmospheric pressure days make this worse than in higher-elevation cities.
- Visible damage from the top when you look down the flue. If you can see a kink, a collapsed section, or a seam that’s pulled apart, that’s not a maintenance issue. That’s a replacement.
See the difference
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After
Before
After
Before
AfterReplacement Cost & What’s Included
A DuraFlex flue liner replacement in Houston typically runs $350 to $900 for a partial section swap, and $1,800 to $3,400 when the entire liner run needs to come out and be replaced from top to bottom. The range depends on three things: how many linear feet of liner you need, whether we can access the top of the chimney from a standard extension ladder or need to set up staging, and whether the old liner comes out cleanly or fights us the whole way. Every quote includes the liner sections themselves, the top plate and rain cap if needed, removal of the old section, and a camera inspection after installation to confirm every seam is locked. We hand you a written price before any work starts, and that number doesn’t change at the door. The entire repair carries our 365-Day Done Right Promise in writing: if a seam fails or the liner shifts within a year, we come back and fix it at no charge.
DIY or Call Us?
You can safely do a visual check from the bottom: shine a flashlight up the flue and look for obvious separations, rust, or kinks. You can also check the firebox for rust flakes after a burn, which tells us something is degrading even if you can’t see it. What you should not do is get on a Houston roof in July, pull a hot liner section out of a chase, or try to muscle a twist-lock seam together from a ladder. Stainless liner edges are sharp enough to need stitches, and a liner that’s half-removed with no support can drop and pinch a hand or worse. If you’ve spotted the problem and you want to know what it costs to fix, that’s what we do. Tell me what you’re seeing, I’ll tell you what it costs to fix it. Call (325) 750-6259 and we’ll schedule a camera look at your liner, usually within one to three business days.
FAQs
A DuraFlex 316L liner in Houston typically lasts 15 to 20 years in a wood-burning fireplace, and closer to 10 to 15 years in a gas appliance that vents continuously, because gas exhaust creates more condensation and that condensation sits against the liner wall longer. Houston’s humidity shortens the lifespan compared to a dry climate like West Texas because the liner stays damp for months at a time between burns. If your liner is past the 15-year mark and showing flaking or seam separation, replacing the affected section now costs less than a full liner failure later. Call (325) 750-6259 for a camera inspection and a written quote.
A small separation at a locking collar can sometimes be re-seated and secured without buying new parts, but a crack, pinhole, or collapsed section cannot be repaired to a standard we’d stand behind. The cost difference between a repair patch and a new section is usually small enough that replacement is the honest recommendation. If Hank’s camera shows a seam that’s simply unlocked, we’ll tell you that and charge you for the labor, not a part you don’t need. Call (325) 750-6259 and we’ll show you exactly what the camera shows before you spend a dollar.
A single section swap takes two to three hours from setup to final camera check. A full liner replacement takes four to six hours, assuming the old liner comes out in one or two pieces and the chase doesn’t have surprises like a wasp nest the size of a football, which happens more often than you’d think in Houston. We’ll give you a written time window before we start, and we don’t leave until the camera confirms every seam is locked. Call (325) 750-6259 to schedule.
We keep common 4-inch, 5.5-inch, and 6-inch DuraFlex sections on the truck, along with top plates, locking collars, and rain caps. If your liner is a less common diameter or a specific 316Ti section, we order it and usually have it in hand within two to three business days. We’ll confirm the exact part number with you before ordering so you’re never paying for the wrong thing. Call (325) 750-6259 for availability on your specific part.
Written by Hank Delano, Owner, Flint Chimney Co Houston at Flint Chimney Co Houston, serving Houston and nearby areas.