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.
DuraFlex Chimney Repair in Yonkers: What to Know First
DuraFlex chimney repair in Yonkers typically runs $400 to $2,800 depending on whether we’re replacing a liner section, rebuilding a crown, or repointing a spalled stack. Most DuraFlex jobs are completed in one visit, with a written price and scope handed to you before we touch anything. As an independent DuraFlex service provider, we’re not affiliated with the manufacturer - which means we can recommend the most honest fix, not the one that moves inventory.
If you own a home with a DuraFlex liner system and you’ve noticed flaking brick, water in the firebox, or a sulfur smell after rain, this page tells you exactly what’s probably going on and what it costs to fix. Call (551) 212-3526 for a written estimate.
How DuraFlex Products Fail - and How We Fix Them
- DuraFlex Pro liner seam separation at the first flue tile offset. We see this constantly in homes along the Yonkers waterfront corridor. The Pro series single-wall corrugated liner flexes more than the smooth-wall models, and at the point where the flue tile changes direction, years of expansion and contraction work the seam crimp loose. Symptom: you smell smoke in upstairs rooms after the first fire. Fix: we cut out the failed section and splice in fresh Pro liner with a stainless steel connector, then camera-scan the full length to confirm the lap joints are seated.
- DuraFlex SW (smooth wall) ovalization from freeze-thaw cycles. Yonkers winters put a real beating on exterior chimneys. The smoother wall profile of the SW series is efficient, but in an uninsulated chase or a stack exposed on three sides, repeated ice expansion can slightly ovalize the liner. That distortion cracks the mortar crown around the flue tile. Symptom: water on the smoke shelf after rain, not after fires. Fix: repointing the crown and, when the ovalization is beyond spec, a full liner replacement with the gauge matched to the original.
- DuraFlex 316L vs 304 alloy confusion on a previous install. Here’s a parts nuance most homeowners don’t get from DuraFlex’s site: the 316L alloy is for gas, the 304 for wood. If a prior contractor used 316L liner on a wood-burning fireplace, the molybdenum in the alloy doesn’t help anything - but it doesn’t fail either. What actually matters is whether the liner was sized correctly. We regularly pull 6-inch liners out of flues that measured 7 inches before a different crew poured a surround. Symptom: poor draft and backpuffing. Fix: measure the true flue cross-section with a laser, in writing, before ordering any replacement sections.
- DuraFlex single-ply flex showing pinhole corrosion at the corrugation valleys. This is what a lazy cleaning schedule actually costs you. Class III creosote holds moisture against the corrugation folds, and the moisture eats through the thin valleys between the ridges. We use a video camera on every service call, and this failure is easy to miss from the top with a flashlight. Symptom: rust staining on the outside of the liner or fine metallic flakes in the firebox. Fix: if the corrosion is isolated to one section, we replace it. If it runs the length, we quote a full liner job with a written side-by-side comparison against HeatShield resurfacing.
- DuraFlex zero-clearance flue adapters backing off at the appliance collar. Yonkers has thousands of older pre-fab fireplaces tucked into 1990s row houses and split-levels. The twist-lock adapter between a DuraFlex liner and a factory-built firebox loosens over time from the differential movement between the metal firebox and the masonry chase. Symptom: a faint creosote smell in the wall cavity, no visible firebox damage. Fix: we re-seat the adapter with high-temp silicone rated for continuous flue temperatures and add a mechanical band clamp where the manufacturer permits. We photograph the before and after for your record.
Our DuraFlex Chimney Repair Process

Every DuraFlex job we run in Yonkers follows the same six steps. You’ll know the number before we start, and you’ll walk away with pictures of exactly what was done.
- 1
You call and we talk to a person. Our phone is answered live, 24/7. We ask what you’re seeing, not what a previous contractor told you.
- 2
We camera-scan the flue, top to smoke chamber. This is an NFPA 211 Level 2 inspection, included in every visit. Corrine Halstead runs a camera before and after every job, and that footage is yours.
- 3
We hand you a written price with a written scope. This is Clause 1 of the Haven Standard. No verbal ranges, no “we’ll see once we’re in there.” The price on the paper is the price you pay.
- 4
We repair with parts sourced from DuraFlex, HeatShield, Gelco, Olympia Chimney, Famco, and Copperfield. We spec OEM or quality aftermarket based on what’s actually better for your flue, not what’s on the truck. For DuraFlex liners, we default to DuraFlex sections unless there’s a documented reason to substitute.
- 5
We document the finished work. Post-repair camera scan, photographs of every connection and crown patch. The photo record is Clause 4 of the Haven Standard, and it’s included as standard - not an add-on charge.
- 6
We issue the 365-Day Done Right Promise. If the repair doesn’t hold, we make it right. On paper, stamped under the Haven Standard.
Before
AfterWhat DuraFlex Chimney Repair Costs in Yonkers
Here are the numbers we quote most often for DuraFlex-related repairs in Yonkers. These are written price ranges, not call-for-a-quote placeholders.
- Liner section replacement (single section, 316L or 304): $400 to $850
- Full DuraFlex liner replacement (typical 20-25 ft flue): $1,900 to $2,800
- Crown repair with waterproofing membrane: $350 to $700
- Mortar repointing near the liner collar: $300 to $600
- Flue adapter re-seat with documentation: $200 to $400
What moves the price: flue height, the condition of the existing clay tile (we may need to break out shattered sections before the fresh liner seats correctly), and whether we’re working from the roof or the firebox. A full rebuild has a different price structure and we’ll walk you through it line by line. Estimates are free and written. Call (551) 212-3526.
Why Yonkers Homeowners Call Level Two Chimney Yonkers for DuraFlex Work

We’re not the biggest chimney company in Yonkers, and we’re not trying to be. We run a camera down every flue before we quote a single dollar, because the camera doesn’t lie, and neither does the quote. Every technician who steps onto your roof is background-checked, uniformed, and licensed - the license number is on your paperwork, not just our website.
Since 2009, we’ve inspected and cleaned more than 38,000 chimneys across Westchester County. Every single one got a written price before work started and a documented photo record when it was done. That’s not our pitch; it’s Clause 4 of the Haven Standard, and it’s how we’ve always operated.
And when a DuraFlex repair turns out to need something different, we don’t stretch a recommendation to fit one brand. We carry HeatShield and Gelco options specifically so the fix matches the flue, not the sales target. If you’ve got a written estimate from another company, bring it in. We’ll give you a free second opinion on it, line by line.
FAQs
Most DuraFlex liner failures in Yonkers can be repaired by section. We splice in a new liner section when the damage is localized - typically at a seam crimp or a single corrosion point. We recommend full replacement when camera footage shows corrosion running more than one-third of the flue length or when the liner has ovalized beyond the manufacturer’s tolerance. Either way, you see the footage and the written recommendation before you approve anything. Call (551) 212-3526 for a camera-scan inspection and a written quote.
No, and here’s what actually matters. Major liner manufacturers, including DuraFlex, honor warranty claims that are documented. That means your paperwork needs to show the repair scope, the parts used, and the before-and-after condition of the flue. We provide exactly that - a written scope, photos, and camera scan footage - on every job. If your liner is still under DuraFlex warranty, our documentation supports your claim. We never tell you what to say to the manufacturer; we hand you the record.
Most section replacements and crown repairs are done the same day. A full liner replacement usually takes four to six hours depending on flue height and roof access. We show up with the parts ordered ahead of time, priced in writing, so there’s no surprise run to a supply house. You get a text when the technician is on the way, per the Haven Standard.
Stop using the fireplace. If the liner is compromised, you’re drafting smoke and carbon monoxide into wall cavities or living space. That’s not a scare tactic; it’s physics. A cracked crown or failed liner section is a fire and CO risk, not a cosmetic issue. We don’t run urgency theatre - no countdowns, no pressure - but we will tell you plainly when the fireplace should stay cold until the repair is done.
Yes. We work with HeatShield and Gelco systems as well, and we carry parts from Olympia Chimney, Famco, and Copperfield. When we repair a DuraFlex system, we default to DuraFlex sections; when a different product makes more sense for your flue, we tell you why in writing. The decision is yours.
Written by Corrine Halstead, Owner, Level Two Chimney Yonkers at Level Two Chimney Yonkers, serving Yonkers and nearby areas.





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