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 Cap & Crown in Denton: What to Know First
We provide independent DuraFlex chimney cap and crown service in Denton, TX, with most inspections scheduled within a few days and repairs completed on the next visit once parts are confirmed. A written price arrives before any work starts, and every job includes a camera-scan inspection with a documented photo record under Clause 4 of the Haven Standard. This page is for Denton homeowners who already know they have a DuraFlex flue system and need the cap or crown addressed by someone who understands how that specific liner interacts with what’s above the roofline. Call us at (940) 373-6912 to book.
How DuraFlex Products Fail - and How We Fix Them
- DuraFlex SW (stainless wall) liners with factory termination caps: The stamped stainless cap that ships with many SW installations uses a light-gauge retention band. In Denton, where spring wind gusts off the prairie regularly hit 50-plus mph and summer UV degrades the neoprene gasket, that band loosens and the cap tilts or blows off entirely. We replace it with a Gelco or Famco multi-flue cap in 304 or 316 stainless, secured with through-bolt mounts to the crown rather than friction-fit to the flue tile.
- DuraFlex AL (aluminum) liners in gas-venting applications: The AL series cap is aluminum-only, and when a Denton homeowner converts from gas logs back to wood burning without swapping the termination, the cap overheats and sags. We see this in the older ranch homes near Sequoia Park where original owners installed AL for a gas insert in the 2010s. The fix is a full cap upgrade to stainless, matched to a DuraFlex SW or compatible Olympia Chimney liner if the AL is no longer code-compliant for solid fuel.
- DuraFlex Pro and Pro-HT crown interface: These higher-temp liners have a wider flue collar that overhangs the clay tile crown more aggressively than standard flex liners. The overhang traps water against the crown’s edge, and in Denton’s freeze-thaw cycle - typically 20 to 30 nights below freezing each winter - that water spalls the crown face in three to five years. We cut back the overhang, seal with a silicone-modified crown coat, and install a cap with a deeper skirt to shed water past the crown edge.
- DuraFlex relining jobs where the original mason left a flush crown: A flush or negative-pitch crown was common in Denton construction from the 1970s through the early 2000s, especially in the neighborhoods north of University Drive. DuraFlex liners need a positive-pitch crown with at least a 2-inch overhang to keep water from running back toward the flue opening. We form and pour a new concrete crown with proper drip edge, or apply a sloped crown coat system when the existing concrete is structurally sound.
- Multi-flue DuraFlex installations with inadequate clearance: When two DuraFlex liners terminate side by side under a single cap, the factory spacing spec is 4 inches minimum between flue collars. We’ve found Denton jobs where the original installer squeezed them to 2 or 3 inches to fit a smaller cap. The flues overheat each other’s caps, accelerating corrosion. We measure with a feeler gauge, document the actual clearance with photos, and specify either a wider custom cap or separate single-flue caps with spark arrestor screens.
Our DuraFlex Chimney Cap & Crown Process

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Booking and arrival: You call (940) 373-6912 and reach a live person. We confirm your DuraFlex model if you know it, schedule the inspection, and text you when your technician is en route. Background-checked, uniformed crews only.
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NFPA 211 Level 2 camera inspection: We run a chimney camera down the full DuraFlex flue to Class A or B condition, documenting liner wall integrity, joint alignment, and any creosote class. The camera doesn’t guess - and neither do I. You see the footage before we discuss the cap or crown.
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Crown and cap diagnostics: Above the roofline, we probe the crown for spalling, measure pitch with a level, check cap retention and screen condition, and photograph every finding. If your DuraFlex is still under OEM warranty, we note which repairs preserve that coverage and which would void it.
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Written scope and price: Before any tool touches your chimney, you receive a written price, written scope, and written warranty. This is Haven Standard Clause 1. No exceptions. If you have a competitor’s written estimate, we’ll review it free.
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Parts selection and repair: We source DuraFlex-compatible caps through our Haven buying network, or specify HeatShield, Gelco, or Famco when aftermarket quality matches or exceeds OEM at a better price. Crown repairs use silicone-modified concrete coatings or full pour-back depending on structural need.
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Final camera verification and documentation: We run the camera again to confirm no debris entered during the repair, test draft with a manometer, and deliver your documented photo record under Haven Standard Clause 4. The 365-Day Done Right Promise applies from this moment.
Before
AfterWhat DuraFlex Chimney Cap & Crown Costs in Denton
| Service | Typical Range | What Moves the Price |
|---|---|---|
| DuraFlex cap replacement (standard single-flue) | $340 - $580 | Stainless grade (304 vs. 316), screen mesh size, whether flue collar needs re-forming |
| Multi-flue cap for dual DuraFlex liners | $620 - $940 | Width required, custom vs. stock, mounting method (crown bolts vs. flue clamp) |
| Crown coating (silicone-modified, sloped) | $480 - $720 | Crown square footage, number of flue penetrations, surface prep needed |
| Full crown replacement with pour-back | $1,400 - $2,200 | Crown dimensions, access difficulty (roof pitch, height), whether flue collars must be re-set |
| Cap + crown combo (common for aging systems) | $1,200 - $2,600 | Extent of hidden water damage revealed after cap removal |
These are Denton-market prices for DuraFlex-specific work, accounting for our material sourcing through the Haven network. The only way to know your exact number is an on-site inspection. Estimates are free. Call (940) 373-6912.
Why Denton Homeowners Call Emberly Chimney Cleaners Denton for DuraFlex Work

We’ve inspected and cleaned more than 38,000 chimneys since 2009, and a growing share of our Denton work involves DuraFlex systems installed during the relining boom of the last decade. Corrine Halstead and our crew know the difference between a DuraFlex AL termination that just needs a cap swap and one that’s telling you the liner itself is mis-specified. Our 365-Day Done Right Promise means if the cap leaks or the crown coating cracks, we return and make it right. We also service HeatShield and Gelco systems, so when a DuraFlex job reveals a compatible component from another brand, we don’t force an unnecessary full replacement. Every technician is background-checked, uniformed, and named before arrival. License information is on every page we publish.
FAQs
It depends on what we do and which DuraFlex series you own. Cap replacement with DuraFlex OEM parts preserves warranty coverage on the liner itself. Using quality aftermarket caps from Gelco or Famco - which we often do for better wind resistance in Denton - does not void the liner warranty unless the cap physically alters the flue collar or liner termination. We document which approach we’re taking on your written scope before starting, so there’s no ambiguity. Call (940) 373-6912 and we’ll check your specific installation.
The cap is metal and sits on top; the crown is concrete and forms the roof of your chimney structure. If the cap is missing, corroded, or improperly screened, that’s a cap job. If the concrete crown is cracked, spalled, or sloped back toward the flue, water is getting into the masonry and the crown needs coating or replacement. During our inspection, we show you camera footage of the flue interior and photos of the crown surface so you can see which problem is active. Many Denton jobs need both. Estimates are free - call (940) 373-6912.
We stock common DuraFlex-compatible caps and crown materials through our Haven buying network, and we source directly from Olympia Chimney and Famco for faster turnaround than ordering through general distributors. Most standard cap replacements in Denton are completed within a week of inspection. Custom caps or rare DuraFlex Pro-HT termination components may take 10 to 14 days. We tell you the lead time in writing before you commit. Call (940) 373-6912 to check current availability.
New liners often vent hotter, faster flue gases than the old clay tile they replaced. That thermal cycling stresses the crown concrete, especially if the original crown was thin or poorly pitched. DuraFlex Pro and Pro-HT liners run particularly hot. In Denton’s climate, where hard freezes follow warm days, the stress accelerates. The liner isn’t the problem; the crown was likely marginal before the relining. We assess this with a hammer test and moisture meter during inspection. Call (940) 373-6912 for a camera scan and crown evaluation.
A quality stainless cap in 304 grade lasts 15 to 20 years in Denton’s conditions; 316 grade extends that significantly. Our silicone-modified crown coatings carry a 10-year performance expectation when applied to sound concrete. Full crown replacements, properly formed and cured, should outlast the cap. The 365-Day Done Right Promise covers workmanship regardless. For a specific projection on your chimney, we need to see the crown condition and cap spec. Call (940) 373-6912 for a free estimate.
Written by Corrine Halstead, Owner, Emberly Chimney Cleaners Denton at Emberly Chimney Cleaners Denton, serving Denton and nearby areas.





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