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.
Gelco Flue Liner Replacement: The Oakland Owner’s Guide
Gelco flue liner replacement in Oakland typically runs $2,800-$5,400 installed, depending on flue height, diameter, and whether the existing top plate and collar can be reused. We stock Gelco-compatible 316Ti stainless and aluminized replacement liners for the most common residential diameters - 6″, 7″, and 8″ - and can usually inspect, measure, and quote same-day. Most Oakland homeowners discover the issue during a routine sweep when our camera shows gaps, corrosion scaling, or separation at the collar joint.
Which Gelco Models This Applies To
Gelco manufactured several liner series over the years, and the part you need depends on when your system was installed. The Gelco Pro-Line (black top plate with stamped model number) and the earlier Gelco Standard (silver collar, no suffix marking) are the two we encounter most often in Oakland homes built between 1985 and 2010. The Pro-Line uses a proprietary twist-lock collar at the top plate that is not interchangeable with standard clamp-style replacements - a compatibility gotcha that has sent more than one homeowner back to the supplier after ordering the wrong kit.
To identify yours: check the top plate inside the firebox or at the chimney crown for a stamped code beginning with “GP-” (Pro-Line) or a plain “G-” prefix (Standard). If the tag is missing, we measure the inner flue diameter at the thimble and the total run from firebox to crown. Gelco Pro-Line 6″ kits measure 6.25″ outer diameter at the collar; Standard series run true 6″. We source replacement liners through Haven’s buying network from Gelco, Olympia Chimney, and Famco - the Olympia 316Ti equivalent matches Pro-Line collar geometry exactly and carries the same 20-year thermal warranty, usually at lower cost.
Signs Your Gelco Flue Liner Replacement Is Failing

- White or green powder on the liner walls. This is aluminum oxide or chloride corrosion, accelerated by Oakland’s marine air carrying salt inland through the Carquinez gap. Once the surface pits, the liner’s rated wall thickness drops below UL 1777 minimums.
- Smoke smell in upstairs rooms when the fireplace is not in use. Gelco liners fail at the upper collar joint first; a separated collar lets downdraft pull smoke and CO into wall cavities. We found this exact pattern in a 1923 Temescal bungalow last March.
- Chunks of clay or tile in the firebox. Your Gelco liner was installed inside an original clay flue. When the liner shrinks from thermal cycling or corrodes through, pieces of the old clay shell fall past the gap. The liner is no longer protecting the masonry.
- Visible gaps in the camera scan at the smoke chamber. Gelco’s Standard series used a single-wall flex section in the smoke chamber on some kits. That section fatigues faster than the main run and separates at the crimp. The camera shows a dark crescent where liner should be continuous.
- Water staining on the firebox back wall. A compromised liner loses its ability to carry combustion moisture up and out. In Oakland’s wet winters, that moisture condenses in the flue and weeps through any breach, carrying acidic residue with it.
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AfterReplacement Cost & What’s Included
| Scope | Price Range |
|---|---|
| Gelco-compatible liner, 6″ x 20′, basic top plate reuse | $2,800-$3,600 |
| Gelco-compatible liner, 7″-8″ x 25’+, new top plate & collar | $3,800-$4,800 |
| Full Pro-Line kit with insulated wrap, clay flue removal | $4,200-$5,400 |
| NFPA 211 Level 2 camera inspection & photo record | Included |
What drives the range: flue height (a three-story Montclair hills run vs. a single-story Maxwell Park ranch), diameter, and whether we can extract the old liner without breaking the surround. Every quote is written before work starts - Clause 1 of the Haven Standard - and includes the liner, all fittings, labor, disposal, and a documented photo record under Clause 4. We warranty the installation for 365 days under our Done Right Promise; the liner itself carries the manufacturer’s thermal warranty, 20 years on 316Ti stainless.
DIY or Call Us?

Here’s what you can safely check yourself: confirm the model stamp on the top plate, measure your flue diameter with a tape, and look for the symptom signs above. What you should not attempt: pulling a stuck liner from a two-story flue, cutting a new top plate opening, or working on the crown without fall protection. A Gelco liner under tension can bind in the clay flue and snap back; the edges of 316Ti stainless are sharp enough to open a hand to the bone. Corrine Halstead has seen three self-installs in Oakland that ended with a liner kinked halfway down, blocking the flue completely. The camera doesn’t speculate - and neither do I.
If you have the model number and flue dimensions, call us at (628) 300-1701. We’ll confirm compatibility from our stock sheet, schedule the inspection, and give you a written price before anyone touches a tool.
FAQs
A properly installed Gelco 316Ti stainless liner lasts 15-25 years in Oakland’s climate, though homes within two miles of the Bay or with frequent fog exposure often see corrosion at the lower end of that range. Aluminized Gelco liners, common in 1990s installations, typically fail at 10-15 years. Call (628) 300-1701 and we’ll camera-scan to tell you exactly where yours stands - estimates are free.
Localized damage at the top collar can sometimes be addressed with a Gelco-compatible replacement collar kit, but only if the main liner run shows no pitting or separation on camera. HeatShield cerfractory resurfacing works for minor smoke chamber gaps but cannot restore wall thickness lost to corrosion. We never recommend repair over replacement without photo evidence you can see for yourself. Call (628) 300-1701 for a free second opinion on any written estimate.
Most Gelco flue liner replacements in Oakland are completed in one day, assuming standard two-story height and no clay flue demolition. Complex extractions or homes with steep roof pitches, like those in the Montclair hills, may extend to a second day. We assign a named technician, send a text when they’re en route, and leave you with a documented photo record under Haven Standard Clause 4.
We carry Gelco-compatible 316Ti replacement liners in 6″, 7″, and 8″ diameters and standard lengths up to 30′, plus Pro-Line and Standard collar adapters, on our Oakland service trucks. Less common diameters or custom top plate configurations we source through Haven’s buying network, usually within 48 hours. Call (628) 300-1701 with your model stamp and we’ll confirm stock before we book.
Written by Corrine Halstead, Owner, Level Two Chimney Oakland at Level Two Chimney Oakland, serving Oakland and nearby areas.





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