Level 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.
Before
After
Before
After
Before
AfterDuraFlex Flue Liner Replacement: The Los Angeles Owner’s Guide
If your DuraFlex flue liner has cracked, corroded, or separated at a seam, we stock and install DuraFlex-compatible liner replacement throughout Los Angeles, with most jobs running $1,800 to $3,800 installed and completed in a single visit. The liner is the stainless steel tube that carries smoke, heat, and combustion gases from your fireplace or furnace up and out of the chimney; when it fails, those gases can leak into wall cavities or the living space. You usually find out about it one of three ways: a chimney inspection flags it, you smell smoke or exhaust inside the house, or you see rust flakes and white staining on the exterior brick.
Which DuraFlex Models This Applies To
DuraFlex makes two main liner families: the 316L stainless steel line for gas and oil appliances, and the heavier-gauge AL29-4C stainless for high-efficiency gas furnaces that produce corrosive condensate. The part number is printed on the liner itself, usually stamped near the bottom connector. The critical specification is the inner diameter; DuraFlex runs 3″, 4″, 5″, 6″, 7″, and 8″, and a 6″ liner is not interchangeable with a 6-5/8″ liner. If your existing liner was sized for an open fireplace and you’ve since converted to gas inserts or a direct-vent unit, we may recommend a different diameter, and that changes the hardware, the cap, and the connector plate, not just the tube. We install genuine DuraFlex components, and we also stock high-grade aftermarket stainless that meets the same UL 1777 standard at a lower price when the application allows it. Alcott Chimney Sweep is an independent contractor; we’re not a DuraFlex factory outlet, which means we’ll tell you when an aftermarket equivalent does the job and when it doesn’t.
Signs Your DuraFlex Flue Liner Replacement Is Failing
- Rust flakes or brown staining on the fireplace floor or smoke chamber. This means the stainless has begun oxidizing, usually where a previous installer’s connector or sealant failed and trapped moisture against the metal. In Los Angeles, the specific wicking effect of coastal fog condensing against cool liners in the morning accelerates this in neighborhoods from Venice up through Pacific Palisades.
- A smell like wet ash or sulfur inside the house, even when you haven’t used the fireplace. That’s combustion residue and moisture being pulled back down the flue when the liner can no longer maintain a thermal barrier. The odor is most noticeable in the early evening when outdoor temperatures drop.
- Cracking sounds from inside the chimney during the first fire of the season. Metal expands when heated, but here in LA the liner has spent six or eight months contracting through warm, dry weather. The first cold cycle causes lateral stress at the seams, and that’s where liners separated at the seam tend to make themselves known.
- White efflorescence, flaking mortar, or crumbling bricks near the top of the chimney. These are signs of water getting behind the liner and into the masonry. Once moisture is in the chase, the liner is usually compromised somewhere above the roofline.
- Carbon monoxide detector activation or visible soot streaks on walls near the chimney chase. Gas appliances vent carbon monoxide at much lower temperatures than wood, and a liner breach lets those gases take the path of least resistance, which is sideways through the wall. If this is happening, call us before using the fireplace again.
Replacement Cost & What’s Included
Installed DuraFlex flue liner replacement in Los Angeles typically runs $1,800 to $3,800, depending on chimney height, liner diameter, whether the old liner is stubborn to extract, and the condition of the chase top. A single-story Woodland Hills ranches with a straight, accessible flue sits at the lower end; a two-story Silver Lake bungalow with a partially collapsed clay tile flue sits at the upper end. Every quote includes the liner, top plate, cap, connector, and labor. We write the full price before any work begins, and that number doesn’t move unless we both agree to change scope. The work includes a written 365-Day Done Right Promise: if the liner install fails within a year, you call us and we’re back out at no charge.
DIY or Call Us?
You can safely inspect the visible parts: look at the cap with binoculars, check the firebox for rust flakes, and note any unusual odor. A full DuraFlex flue liner replacement is not a safe DIY project. Working on a roof with clean-out tools, removing a failed liner that may be secured at multiple points, and properly sealing the top plate requires someone who understands code clearances, termination height, and how a liner connects to your specific appliance. If you’d like a professional assessment before deciding, call us at (336) 863-3889 and we’ll send a technician who will show you camera images of exactly what’s going on inside your flue.
FAQs
A properly installed DuraFlex 316L liner in a wood-burning fireplace typically lasts 15 to 25 years, though gas-only systems in coastal Los Angeles neighborhoods may need replacement sooner because of acidic condensate. The stainless itself doesn’t wear out so much as the installation does: bad connections, undersized or oversized fit, and water intrusion at the cap cause most premature failures.
Small pinholes or a single failed seam can sometimes be patched with a stainless repair section, but any liner showing distortion, multiple seam separations, or corrosion across more than a quarter of its circumference should be replaced. Repairs on a structurally compromised liner buy months, not years, and they’re not something we’ll recommend if the camera inspection shows ongoing deterioration. Call (336) 863-3889 for an exact quote; estimates are free.
Most Los Angeles single-story homes are done in four to six hours, and two-story homes with longer runs or difficult extraction can take a full day. We schedule the job in one visit, and you’ll have a working fireplace by evening.
Yes, we stock 3″ through 8″ DuraFlex and compatible liners, caps, plates, and connectors on our trucks, so in most cases we can complete the replacement the same day we diagnose it. Alcott Chimney Sweep also carries HeatShield and Gelco systems if resurfacing turns out to be a better fit than a full liner swap.
If you’re seeing flakes, smelling sulfur, or your CO detector keeps going off, there’s a reason, and it’s usually a specific one we can identify with a camera inspection. Call (336) 863-3889 and we’ll send a technician called Ruben Castellano, owner of Alcott Chimney Sweep, who grew up in Boyle Heights and has spent the better part of two decades working chimneys across Los Angeles, from the Craftsman bungalows of Silver Lake to the older ranch homes out in the Valley. He learned the trade through the HVAC and building trades program at East Los Angeles College, and he’ll show you camera images of exactly what’s going on inside your flue before any work starts. You’ll know the technician’s name and see their photo before we arrive, and the written price comes before any tool leaves the truck.
Written by Ruben Castellano, Owner, Alcott Chimney Sweep at Alcott Chimney Sweep, serving Los Angeles and nearby areas.