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.
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AfterDuraFlex Chimney Cap & Crown in Boulder: What to Know First
We provide independent DuraFlex chimney cap and crown service in Boulder, with most jobs quoted in writing during the first visit and completed within one to two business days. A standard DuraFlex cap replacement runs $340-$620; crown repair or coating typically falls between $480-$1,100 depending on accessibility and flue count. We are not affiliated with or authorized by DuraFlex; we source parts through our Haven buying network and install to manufacturer specifications without voiding your existing warranty coverage.
This page is for Boulder homeowners who know they’ve got DuraFlex components on their chimney and need straight answers on what’s failing, what it costs, and who can fix it without the runaround. Corrine Halstead and our crew have worked DuraFlex systems from Mapleton Hill’s older masonry to the newer builds up near Chautauqua. Call (970) 598-0453 for a free estimate, or read on for the details.
How DuraFlex Products Fail - and How We Fix Them
- DuraFlex SW (stainless wall) cap separation at the storm collar. The SW series uses a lighter-gauge storm collar than competing all-fuel liners, and Boulder’s freeze-thaw cycles from November through March work the seal loose. We find the collar lifted or the sealant cracked, letting water track down between the liner and the masonry. Our fix: remove the cap, reseat the collar with high-temp silicone rated to 600°F, and install a Gelco or Famco replacement cap with a deeper overhang than the OEM spec.
- DuraFlex AL (aluminum) cap corrosion at the mesh screen. The AL series is rated for gas and oil only, but Boulder homeowners sometimes inherit these on wood-burning conversions. The 304 stainless mesh on the OEM cap isn’t matched to the aluminum body, and galvanic corrosion eats the screen welds within 4-6 years. We replace with an Olympia Chimney aluminum-body cap or, if you’ve converted to wood, upsell to a full stainless cap and liner evaluation.
- DuraFlex Pro multi-flue cap water intrusion at the partition joints. The Pro series multi-flue caps ship with silicone gaskets at the partition walls that degrade faster at altitude; Boulder’s UV index runs 25-30% higher than sea level, and the gasket hardens in 18-24 months. Water crosses between flues, staining the smoke chamber below. We pull the cap, replace with copper or stainless partition flashing, and reseal with a product rated for 7,000+ foot exposure.
- DuraFlex crown coating failure on poured concrete crowns. When a DuraFlex liner is retrofitted through an existing crown, the coring leaves a gap that gets packed with mortar. That mortar shrinks differently than the DuraFlex termination seal, and Boulder’s dry winters pull moisture out fast. The crown cracks radially from the penetration. We grind back to sound concrete, apply HeatShield CrownCoat in two passes, and install a cap with a minimum 3-inch overhang to shed snow load off the Flatirons.
- DuraFlex telescoping cap collapse on steep-pitch roofs. The telescoping section on DuraFlex factory-built caps uses a friction fit that loosens with thermal cycling; in Boulder, that’s 40°F+ swings in a single March afternoon. The cap tilts, the mesh gaps, and squirrels get in. We replace with a fixed-height Famco cap sized to the exact flue projection, or fabricate a custom cricket-supported assembly for pitches over 8/12.
Our DuraFlex Chimney Cap & Crown Process
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Call and schedule. A live person answers, checks availability, and notes your DuraFlex model if you know it. We pull your address for roof pitch and access notes from satellite imagery before we arrive.
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NFPA 211 Level 2 inspection with camera. Corrine or a named technician runs the camera down the flue, documents the liner condition, and checks the crown with a moisture meter. The camera doesn’t guess. Neither do I.
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Written price and scope. Before any work starts, you get a written price, a written scope, and a written warranty - Haven Standard Clause 1. No exceptions. If the cap is OEM-available, we quote both OEM and our recommended aftermarket option with the trade-offs explained.
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Parts procurement and installation. We source DuraFlex-compatible caps and crowns through our Haven buying network; most common sizes are in our Boulder warehouse, custom orders take 24-48 hours. Installation includes new fasteners, sealant, and a water test with the hose.
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Final camera run and photo record. Haven Standard Clause 4 requires it: we camera the flue again, photograph the completed crown and cap from roof level, and upload everything to your job record. You get the link before we leave.
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365-Day Done Right Promise. If the cap leaks, the crown cracks, or anything isn’t right, we make it right. The promise is stamped on every job.
BeforeAfterWhat DuraFlex Chimney Cap & Crown Costs in Boulder
| Service | Typical Range | What Moves the Price |
|---|---|---|
| DuraFlex single-flue cap replacement (standard height) | $340-$480 | Roof pitch, flue diameter, stainless vs. galvanized |
| DuraFlex multi-flue cap replacement | $520-$780 | Flue count, partition wall condition, custom sizing |
| Crown repair with HeatShield CrownCoat | $480-$850 | Crown square footage, crack depth, coring repair around liner |
| Crown rebuild (partial, above roofline) | $1,100-$1,800 | Scaffolding need, rebar exposure, liner support bracket rework |
| Telescoping cap conversion to fixed-height | $420-$650 | Flue projection measurement, cricket fabrication for steep pitch |
These are real Boulder prices for real DuraFlex jobs we’ve completed in the last 18 months, from homes near Baseline to the canyons west of town. Every estimate is free, and we honor our Free Second Opinion on any competitor’s written quote. Call (970) 598-0453 for your exact number.
Why Boulder Homeowners Call Emberly Chimney Cleaners Boulder for DuraFlex Work
We’ve inspected and cleaned more than 38,000 chimneys since 2009, and a growing share of Boulder’s housing stock runs DuraFlex liners from the 2010-2020 retrofit boom. Corrine knows the difference between an SW termination that needs a new seal and one that needs a full cap redesign because she’s camera-documented both, hundreds of times, in this county.
Our Haven Standard means background-checked, uniformed technicians with license numbers on the page and a text when we’re en route. It means materials from DuraFlex, HeatShield, Gelco, Olympia Chimney, Famco, and Copperfield procured through our buying network to keep customer prices honest. And it means that when your DuraFlex part is backordered, we have cross-compatible options we’ve already tested in Bouldon’s climate - not a shrug and a return visit.
We’re independently owned and operated, not a franchise, and we’ve been at this since 2009.
FAQs
No. As an independent DuraFlex service provider, we install to manufacturer specifications using OEM or equivalent parts; warranty coverage remains intact provided the original installation was code-compliant. We document our work with photos and serial numbers to support any future warranty claim you need to file. Call (970) 598-0453 if you want us to review your warranty paperwork before we start.
Most single-flue cap replacements are completed in 90 minutes to two hours, including the inspection, installation, and final camera run. Multi-flue caps or jobs requiring crown repair add two to four hours. We book by the job, not the hour, so the price doesn’t change if we hit frozen fasteners on a January morning in North Boulder.
We can source OEM DuraFlex caps through our Haven buying network, and we quote that option when it’s available. Often we recommend a Gelco, Famco, or Olympia Chimney equivalent with better snow-load geometry or longer gasket life at altitude; we’ll show you both prices and explain the difference. The decision is yours, and it’s in writing before work starts.
Hairline cracks in a crown can wait one season if there’s no spalling (surface flaking) and the cap overhang is shedding water properly. We camera the flue to confirm no water damage below, document the crack width with a photo, and note it in your record. If the crack opens to 1/8 inch or water is reaching the liner, we recommend CrownCoat before the next freeze cycle. Call (970) 598-0453 and we’ll give you a free assessment with the camera footage to decide.
We stock common DuraFlex-compatible cap sizes for 6-inch through 10-inch flues at our Boulder warehouse. Less common sizes and custom multi-flue configurations ship within 24-48 hours from our network; we schedule the job for after parts arrival so your flue is never open overnight. For urgent water intrusion, we can install a temporary cap same-day while the permanent part ships.
Written by Corrine Halstead, Owner, Emberly Chimney Cleaners Boulder at Emberly Chimney Cleaners Boulder, serving Boulder and nearby areas.